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authorMike Pagano <mpagano@gentoo.org>2022-03-11 06:30:48 -0500
committerMike Pagano <mpagano@gentoo.org>2022-03-11 06:30:48 -0500
commit549c51ef7f24622f906ad3941b9dcea359ada5e1 (patch)
treef2de7b803f3f7fb06ea4256214d043dafb4cfde4
parentLinux patch 5.10.104 (diff)
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Linux patch 5.10.1055.10-1135.10-112
Signed-off-by: Mike Pagano <mpagano@gentoo.org>
-rw-r--r--0000_README4
-rw-r--r--1104_linux-5.10.105.patch3857
2 files changed, 3861 insertions, 0 deletions
diff --git a/0000_README b/0000_README
index f4f4b91a..6fbdd908 100644
--- a/0000_README
+++ b/0000_README
@@ -459,6 +459,10 @@ Patch: 1103_linux-5.10.104.patch
From: http://www.kernel.org
Desc: Linux 5.10.104
+Patch: 1104_linux-5.10.105.patch
+From: http://www.kernel.org
+Desc: Linux 5.10.105
+
Patch: 1500_XATTR_USER_PREFIX.patch
From: https://bugs.gentoo.org/show_bug.cgi?id=470644
Desc: Support for namespace user.pax.* on tmpfs.
diff --git a/1104_linux-5.10.105.patch b/1104_linux-5.10.105.patch
new file mode 100644
index 00000000..aa2a1fc7
--- /dev/null
+++ b/1104_linux-5.10.105.patch
@@ -0,0 +1,3857 @@
+diff --git a/Documentation/admin-guide/hw-vuln/spectre.rst b/Documentation/admin-guide/hw-vuln/spectre.rst
+index 985181dba0bac..6bd97cd50d625 100644
+--- a/Documentation/admin-guide/hw-vuln/spectre.rst
++++ b/Documentation/admin-guide/hw-vuln/spectre.rst
+@@ -60,8 +60,8 @@ privileged data touched during the speculative execution.
+ Spectre variant 1 attacks take advantage of speculative execution of
+ conditional branches, while Spectre variant 2 attacks use speculative
+ execution of indirect branches to leak privileged memory.
+-See :ref:`[1] <spec_ref1>` :ref:`[5] <spec_ref5>` :ref:`[7] <spec_ref7>`
+-:ref:`[10] <spec_ref10>` :ref:`[11] <spec_ref11>`.
++See :ref:`[1] <spec_ref1>` :ref:`[5] <spec_ref5>` :ref:`[6] <spec_ref6>`
++:ref:`[7] <spec_ref7>` :ref:`[10] <spec_ref10>` :ref:`[11] <spec_ref11>`.
+
+ Spectre variant 1 (Bounds Check Bypass)
+ ---------------------------------------
+@@ -131,6 +131,19 @@ steer its indirect branch speculations to gadget code, and measure the
+ speculative execution's side effects left in level 1 cache to infer the
+ victim's data.
+
++Yet another variant 2 attack vector is for the attacker to poison the
++Branch History Buffer (BHB) to speculatively steer an indirect branch
++to a specific Branch Target Buffer (BTB) entry, even if the entry isn't
++associated with the source address of the indirect branch. Specifically,
++the BHB might be shared across privilege levels even in the presence of
++Enhanced IBRS.
++
++Currently the only known real-world BHB attack vector is via
++unprivileged eBPF. Therefore, it's highly recommended to not enable
++unprivileged eBPF, especially when eIBRS is used (without retpolines).
++For a full mitigation against BHB attacks, it's recommended to use
++retpolines (or eIBRS combined with retpolines).
++
+ Attack scenarios
+ ----------------
+
+@@ -364,13 +377,15 @@ The possible values in this file are:
+
+ - Kernel status:
+
+- ==================================== =================================
+- 'Not affected' The processor is not vulnerable
+- 'Vulnerable' Vulnerable, no mitigation
+- 'Mitigation: Full generic retpoline' Software-focused mitigation
+- 'Mitigation: Full AMD retpoline' AMD-specific software mitigation
+- 'Mitigation: Enhanced IBRS' Hardware-focused mitigation
+- ==================================== =================================
++ ======================================== =================================
++ 'Not affected' The processor is not vulnerable
++ 'Mitigation: None' Vulnerable, no mitigation
++ 'Mitigation: Retpolines' Use Retpoline thunks
++ 'Mitigation: LFENCE' Use LFENCE instructions
++ 'Mitigation: Enhanced IBRS' Hardware-focused mitigation
++ 'Mitigation: Enhanced IBRS + Retpolines' Hardware-focused + Retpolines
++ 'Mitigation: Enhanced IBRS + LFENCE' Hardware-focused + LFENCE
++ ======================================== =================================
+
+ - Firmware status: Show if Indirect Branch Restricted Speculation (IBRS) is
+ used to protect against Spectre variant 2 attacks when calling firmware (x86 only).
+@@ -584,12 +599,13 @@ kernel command line.
+
+ Specific mitigations can also be selected manually:
+
+- retpoline
+- replace indirect branches
+- retpoline,generic
+- google's original retpoline
+- retpoline,amd
+- AMD-specific minimal thunk
++ retpoline auto pick between generic,lfence
++ retpoline,generic Retpolines
++ retpoline,lfence LFENCE; indirect branch
++ retpoline,amd alias for retpoline,lfence
++ eibrs enhanced IBRS
++ eibrs,retpoline enhanced IBRS + Retpolines
++ eibrs,lfence enhanced IBRS + LFENCE
+
+ Not specifying this option is equivalent to
+ spectre_v2=auto.
+@@ -730,7 +746,7 @@ AMD white papers:
+
+ .. _spec_ref6:
+
+-[6] `Software techniques for managing speculation on AMD processors <https://developer.amd.com/wp-content/resources/90343-B_SoftwareTechniquesforManagingSpeculation_WP_7-18Update_FNL.pdf>`_.
++[6] `Software techniques for managing speculation on AMD processors <https://developer.amd.com/wp-content/resources/Managing-Speculation-on-AMD-Processors.pdf>`_.
+
+ ARM white papers:
+
+diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
+index d00618967854d..611172f68bb57 100644
+--- a/Documentation/admin-guide/kernel-parameters.txt
++++ b/Documentation/admin-guide/kernel-parameters.txt
+@@ -4957,8 +4957,12 @@
+ Specific mitigations can also be selected manually:
+
+ retpoline - replace indirect branches
+- retpoline,generic - google's original retpoline
+- retpoline,amd - AMD-specific minimal thunk
++ retpoline,generic - Retpolines
++ retpoline,lfence - LFENCE; indirect branch
++ retpoline,amd - alias for retpoline,lfence
++ eibrs - enhanced IBRS
++ eibrs,retpoline - enhanced IBRS + Retpolines
++ eibrs,lfence - enhanced IBRS + LFENCE
+
+ Not specifying this option is equivalent to
+ spectre_v2=auto.
+diff --git a/Documentation/arm64/cpu-feature-registers.rst b/Documentation/arm64/cpu-feature-registers.rst
+index 328e0c454fbd4..749ae970c3195 100644
+--- a/Documentation/arm64/cpu-feature-registers.rst
++++ b/Documentation/arm64/cpu-feature-registers.rst
+@@ -235,7 +235,15 @@ infrastructure:
+ | DPB | [3-0] | y |
+ +------------------------------+---------+---------+
+
+- 6) ID_AA64MMFR2_EL1 - Memory model feature register 2
++ 6) ID_AA64MMFR0_EL1 - Memory model feature register 0
++
++ +------------------------------+---------+---------+
++ | Name | bits | visible |
++ +------------------------------+---------+---------+
++ | ECV | [63-60] | y |
++ +------------------------------+---------+---------+
++
++ 7) ID_AA64MMFR2_EL1 - Memory model feature register 2
+
+ +------------------------------+---------+---------+
+ | Name | bits | visible |
+@@ -243,7 +251,7 @@ infrastructure:
+ | AT | [35-32] | y |
+ +------------------------------+---------+---------+
+
+- 7) ID_AA64ZFR0_EL1 - SVE feature ID register 0
++ 8) ID_AA64ZFR0_EL1 - SVE feature ID register 0
+
+ +------------------------------+---------+---------+
+ | Name | bits | visible |
+@@ -267,6 +275,23 @@ infrastructure:
+ | SVEVer | [3-0] | y |
+ +------------------------------+---------+---------+
+
++ 8) ID_AA64MMFR1_EL1 - Memory model feature register 1
++
++ +------------------------------+---------+---------+
++ | Name | bits | visible |
++ +------------------------------+---------+---------+
++ | AFP | [47-44] | y |
++ +------------------------------+---------+---------+
++
++ 9) ID_AA64ISAR2_EL1 - Instruction set attribute register 2
++
++ +------------------------------+---------+---------+
++ | Name | bits | visible |
++ +------------------------------+---------+---------+
++ | RPRES | [7-4] | y |
++ +------------------------------+---------+---------+
++
++
+ Appendix I: Example
+ -------------------
+
+diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst
+index bbd9cf54db6c7..e88d245d426da 100644
+--- a/Documentation/arm64/elf_hwcaps.rst
++++ b/Documentation/arm64/elf_hwcaps.rst
+@@ -245,6 +245,18 @@ HWCAP2_MTE
+ Functionality implied by ID_AA64PFR1_EL1.MTE == 0b0010, as described
+ by Documentation/arm64/memory-tagging-extension.rst.
+
++HWCAP2_ECV
++
++ Functionality implied by ID_AA64MMFR0_EL1.ECV == 0b0001.
++
++HWCAP2_AFP
++
++ Functionality implied by ID_AA64MFR1_EL1.AFP == 0b0001.
++
++HWCAP2_RPRES
++
++ Functionality implied by ID_AA64ISAR2_EL1.RPRES == 0b0001.
++
+ 4. Unused AT_HWCAP bits
+ -----------------------
+
+diff --git a/Makefile b/Makefile
+index 6e6efe5516872..ea665736db040 100644
+--- a/Makefile
++++ b/Makefile
+@@ -1,7 +1,7 @@
+ # SPDX-License-Identifier: GPL-2.0
+ VERSION = 5
+ PATCHLEVEL = 10
+-SUBLEVEL = 104
++SUBLEVEL = 105
+ EXTRAVERSION =
+ NAME = Dare mighty things
+
+diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
+index 72627c5fb3b2c..24a1f498b3b5f 100644
+--- a/arch/arm/include/asm/assembler.h
++++ b/arch/arm/include/asm/assembler.h
+@@ -107,6 +107,16 @@
+ .endm
+ #endif
+
++#if __LINUX_ARM_ARCH__ < 7
++ .macro dsb, args
++ mcr p15, 0, r0, c7, c10, 4
++ .endm
++
++ .macro isb, args
++ mcr p15, 0, r0, c7, c5, 4
++ .endm
++#endif
++
+ .macro asm_trace_hardirqs_off, save=1
+ #if defined(CONFIG_TRACE_IRQFLAGS)
+ .if \save
+diff --git a/arch/arm/include/asm/spectre.h b/arch/arm/include/asm/spectre.h
+new file mode 100644
+index 0000000000000..d1fa5607d3aa3
+--- /dev/null
++++ b/arch/arm/include/asm/spectre.h
+@@ -0,0 +1,32 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++
++#ifndef __ASM_SPECTRE_H
++#define __ASM_SPECTRE_H
++
++enum {
++ SPECTRE_UNAFFECTED,
++ SPECTRE_MITIGATED,
++ SPECTRE_VULNERABLE,
++};
++
++enum {
++ __SPECTRE_V2_METHOD_BPIALL,
++ __SPECTRE_V2_METHOD_ICIALLU,
++ __SPECTRE_V2_METHOD_SMC,
++ __SPECTRE_V2_METHOD_HVC,
++ __SPECTRE_V2_METHOD_LOOP8,
++};
++
++enum {
++ SPECTRE_V2_METHOD_BPIALL = BIT(__SPECTRE_V2_METHOD_BPIALL),
++ SPECTRE_V2_METHOD_ICIALLU = BIT(__SPECTRE_V2_METHOD_ICIALLU),
++ SPECTRE_V2_METHOD_SMC = BIT(__SPECTRE_V2_METHOD_SMC),
++ SPECTRE_V2_METHOD_HVC = BIT(__SPECTRE_V2_METHOD_HVC),
++ SPECTRE_V2_METHOD_LOOP8 = BIT(__SPECTRE_V2_METHOD_LOOP8),
++};
++
++void spectre_v2_update_state(unsigned int state, unsigned int methods);
++
++int spectre_bhb_update_vectors(unsigned int method);
++
++#endif
+diff --git a/arch/arm/include/asm/vmlinux.lds.h b/arch/arm/include/asm/vmlinux.lds.h
+index 4a91428c324db..fad45c884e988 100644
+--- a/arch/arm/include/asm/vmlinux.lds.h
++++ b/arch/arm/include/asm/vmlinux.lds.h
+@@ -26,6 +26,19 @@
+ #define ARM_MMU_DISCARD(x) x
+ #endif
+
++/*
++ * ld.lld does not support NOCROSSREFS:
++ * https://github.com/ClangBuiltLinux/linux/issues/1609
++ */
++#ifdef CONFIG_LD_IS_LLD
++#define NOCROSSREFS
++#endif
++
++/* Set start/end symbol names to the LMA for the section */
++#define ARM_LMA(sym, section) \
++ sym##_start = LOADADDR(section); \
++ sym##_end = LOADADDR(section) + SIZEOF(section)
++
+ #define PROC_INFO \
+ . = ALIGN(4); \
+ __proc_info_begin = .; \
+@@ -110,19 +123,31 @@
+ * only thing that matters is their relative offsets
+ */
+ #define ARM_VECTORS \
+- __vectors_start = .; \
+- .vectors 0xffff0000 : AT(__vectors_start) { \
+- *(.vectors) \
++ __vectors_lma = .; \
++ OVERLAY 0xffff0000 : NOCROSSREFS AT(__vectors_lma) { \
++ .vectors { \
++ *(.vectors) \
++ } \
++ .vectors.bhb.loop8 { \
++ *(.vectors.bhb.loop8) \
++ } \
++ .vectors.bhb.bpiall { \
++ *(.vectors.bhb.bpiall) \
++ } \
+ } \
+- . = __vectors_start + SIZEOF(.vectors); \
+- __vectors_end = .; \
++ ARM_LMA(__vectors, .vectors); \
++ ARM_LMA(__vectors_bhb_loop8, .vectors.bhb.loop8); \
++ ARM_LMA(__vectors_bhb_bpiall, .vectors.bhb.bpiall); \
++ . = __vectors_lma + SIZEOF(.vectors) + \
++ SIZEOF(.vectors.bhb.loop8) + \
++ SIZEOF(.vectors.bhb.bpiall); \
+ \
+- __stubs_start = .; \
+- .stubs ADDR(.vectors) + 0x1000 : AT(__stubs_start) { \
++ __stubs_lma = .; \
++ .stubs ADDR(.vectors) + 0x1000 : AT(__stubs_lma) { \
+ *(.stubs) \
+ } \
+- . = __stubs_start + SIZEOF(.stubs); \
+- __stubs_end = .; \
++ ARM_LMA(__stubs, .stubs); \
++ . = __stubs_lma + SIZEOF(.stubs); \
+ \
+ PROVIDE(vector_fiq_offset = vector_fiq - ADDR(.vectors));
+
+diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
+index 89e5d864e9234..79588b5623532 100644
+--- a/arch/arm/kernel/Makefile
++++ b/arch/arm/kernel/Makefile
+@@ -106,4 +106,6 @@ endif
+
+ obj-$(CONFIG_HAVE_ARM_SMCCC) += smccc-call.o
+
++obj-$(CONFIG_GENERIC_CPU_VULNERABILITIES) += spectre.o
++
+ extra-y := $(head-y) vmlinux.lds
+diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
+index 63fbcdc97ded9..3cbd35c82a66c 100644
+--- a/arch/arm/kernel/entry-armv.S
++++ b/arch/arm/kernel/entry-armv.S
+@@ -1005,12 +1005,11 @@ vector_\name:
+ sub lr, lr, #\correction
+ .endif
+
+- @
+- @ Save r0, lr_<exception> (parent PC) and spsr_<exception>
+- @ (parent CPSR)
+- @
++ @ Save r0, lr_<exception> (parent PC)
+ stmia sp, {r0, lr} @ save r0, lr
+- mrs lr, spsr
++
++ @ Save spsr_<exception> (parent CPSR)
++2: mrs lr, spsr
+ str lr, [sp, #8] @ save spsr
+
+ @
+@@ -1031,6 +1030,44 @@ vector_\name:
+ movs pc, lr @ branch to handler in SVC mode
+ ENDPROC(vector_\name)
+
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++ .subsection 1
++ .align 5
++vector_bhb_loop8_\name:
++ .if \correction
++ sub lr, lr, #\correction
++ .endif
++
++ @ Save r0, lr_<exception> (parent PC)
++ stmia sp, {r0, lr}
++
++ @ bhb workaround
++ mov r0, #8
++1: b . + 4
++ subs r0, r0, #1
++ bne 1b
++ dsb
++ isb
++ b 2b
++ENDPROC(vector_bhb_loop8_\name)
++
++vector_bhb_bpiall_\name:
++ .if \correction
++ sub lr, lr, #\correction
++ .endif
++
++ @ Save r0, lr_<exception> (parent PC)
++ stmia sp, {r0, lr}
++
++ @ bhb workaround
++ mcr p15, 0, r0, c7, c5, 6 @ BPIALL
++ @ isb not needed due to "movs pc, lr" in the vector stub
++ @ which gives a "context synchronisation".
++ b 2b
++ENDPROC(vector_bhb_bpiall_\name)
++ .previous
++#endif
++
+ .align 2
+ @ handler addresses follow this label
+ 1:
+@@ -1039,6 +1076,10 @@ ENDPROC(vector_\name)
+ .section .stubs, "ax", %progbits
+ @ This must be the first word
+ .word vector_swi
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++ .word vector_bhb_loop8_swi
++ .word vector_bhb_bpiall_swi
++#endif
+
+ vector_rst:
+ ARM( swi SYS_ERROR0 )
+@@ -1153,8 +1194,10 @@ vector_addrexcptn:
+ * FIQ "NMI" handler
+ *-----------------------------------------------------------------------------
+ * Handle a FIQ using the SVC stack allowing FIQ act like NMI on x86
+- * systems.
++ * systems. This must be the last vector stub, so lets place it in its own
++ * subsection.
+ */
++ .subsection 2
+ vector_stub fiq, FIQ_MODE, 4
+
+ .long __fiq_usr @ 0 (USR_26 / USR_32)
+@@ -1187,6 +1230,30 @@ vector_addrexcptn:
+ W(b) vector_irq
+ W(b) vector_fiq
+
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++ .section .vectors.bhb.loop8, "ax", %progbits
++.L__vectors_bhb_loop8_start:
++ W(b) vector_rst
++ W(b) vector_bhb_loop8_und
++ W(ldr) pc, .L__vectors_bhb_loop8_start + 0x1004
++ W(b) vector_bhb_loop8_pabt
++ W(b) vector_bhb_loop8_dabt
++ W(b) vector_addrexcptn
++ W(b) vector_bhb_loop8_irq
++ W(b) vector_bhb_loop8_fiq
++
++ .section .vectors.bhb.bpiall, "ax", %progbits
++.L__vectors_bhb_bpiall_start:
++ W(b) vector_rst
++ W(b) vector_bhb_bpiall_und
++ W(ldr) pc, .L__vectors_bhb_bpiall_start + 0x1008
++ W(b) vector_bhb_bpiall_pabt
++ W(b) vector_bhb_bpiall_dabt
++ W(b) vector_addrexcptn
++ W(b) vector_bhb_bpiall_irq
++ W(b) vector_bhb_bpiall_fiq
++#endif
++
+ .data
+ .align 2
+
+diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
+index 271cb8a1eba1e..bd619da73c84e 100644
+--- a/arch/arm/kernel/entry-common.S
++++ b/arch/arm/kernel/entry-common.S
+@@ -162,6 +162,29 @@ ENDPROC(ret_from_fork)
+ *-----------------------------------------------------------------------------
+ */
+
++ .align 5
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++ENTRY(vector_bhb_loop8_swi)
++ sub sp, sp, #PT_REGS_SIZE
++ stmia sp, {r0 - r12}
++ mov r8, #8
++1: b 2f
++2: subs r8, r8, #1
++ bne 1b
++ dsb
++ isb
++ b 3f
++ENDPROC(vector_bhb_loop8_swi)
++
++ .align 5
++ENTRY(vector_bhb_bpiall_swi)
++ sub sp, sp, #PT_REGS_SIZE
++ stmia sp, {r0 - r12}
++ mcr p15, 0, r8, c7, c5, 6 @ BPIALL
++ isb
++ b 3f
++ENDPROC(vector_bhb_bpiall_swi)
++#endif
+ .align 5
+ ENTRY(vector_swi)
+ #ifdef CONFIG_CPU_V7M
+@@ -169,6 +192,7 @@ ENTRY(vector_swi)
+ #else
+ sub sp, sp, #PT_REGS_SIZE
+ stmia sp, {r0 - r12} @ Calling r0 - r12
++3:
+ ARM( add r8, sp, #S_PC )
+ ARM( stmdb r8, {sp, lr}^ ) @ Calling sp, lr
+ THUMB( mov r8, sp )
+diff --git a/arch/arm/kernel/spectre.c b/arch/arm/kernel/spectre.c
+new file mode 100644
+index 0000000000000..0dcefc36fb7a0
+--- /dev/null
++++ b/arch/arm/kernel/spectre.c
+@@ -0,0 +1,71 @@
++// SPDX-License-Identifier: GPL-2.0-only
++#include <linux/bpf.h>
++#include <linux/cpu.h>
++#include <linux/device.h>
++
++#include <asm/spectre.h>
++
++static bool _unprivileged_ebpf_enabled(void)
++{
++#ifdef CONFIG_BPF_SYSCALL
++ return !sysctl_unprivileged_bpf_disabled;
++#else
++ return false;
++#endif
++}
++
++ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr,
++ char *buf)
++{
++ return sprintf(buf, "Mitigation: __user pointer sanitization\n");
++}
++
++static unsigned int spectre_v2_state;
++static unsigned int spectre_v2_methods;
++
++void spectre_v2_update_state(unsigned int state, unsigned int method)
++{
++ if (state > spectre_v2_state)
++ spectre_v2_state = state;
++ spectre_v2_methods |= method;
++}
++
++ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
++ char *buf)
++{
++ const char *method;
++
++ if (spectre_v2_state == SPECTRE_UNAFFECTED)
++ return sprintf(buf, "%s\n", "Not affected");
++
++ if (spectre_v2_state != SPECTRE_MITIGATED)
++ return sprintf(buf, "%s\n", "Vulnerable");
++
++ if (_unprivileged_ebpf_enabled())
++ return sprintf(buf, "Vulnerable: Unprivileged eBPF enabled\n");
++
++ switch (spectre_v2_methods) {
++ case SPECTRE_V2_METHOD_BPIALL:
++ method = "Branch predictor hardening";
++ break;
++
++ case SPECTRE_V2_METHOD_ICIALLU:
++ method = "I-cache invalidation";
++ break;
++
++ case SPECTRE_V2_METHOD_SMC:
++ case SPECTRE_V2_METHOD_HVC:
++ method = "Firmware call";
++ break;
++
++ case SPECTRE_V2_METHOD_LOOP8:
++ method = "History overwrite";
++ break;
++
++ default:
++ method = "Multiple mitigations";
++ break;
++ }
++
++ return sprintf(buf, "Mitigation: %s\n", method);
++}
+diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c
+index 17d5a785df28b..2d9e72ad1b0f9 100644
+--- a/arch/arm/kernel/traps.c
++++ b/arch/arm/kernel/traps.c
+@@ -30,6 +30,7 @@
+ #include <linux/atomic.h>
+ #include <asm/cacheflush.h>
+ #include <asm/exception.h>
++#include <asm/spectre.h>
+ #include <asm/unistd.h>
+ #include <asm/traps.h>
+ #include <asm/ptrace.h>
+@@ -806,10 +807,59 @@ static inline void __init kuser_init(void *vectors)
+ }
+ #endif
+
++#ifndef CONFIG_CPU_V7M
++static void copy_from_lma(void *vma, void *lma_start, void *lma_end)
++{
++ memcpy(vma, lma_start, lma_end - lma_start);
++}
++
++static void flush_vectors(void *vma, size_t offset, size_t size)
++{
++ unsigned long start = (unsigned long)vma + offset;
++ unsigned long end = start + size;
++
++ flush_icache_range(start, end);
++}
++
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++int spectre_bhb_update_vectors(unsigned int method)
++{
++ extern char __vectors_bhb_bpiall_start[], __vectors_bhb_bpiall_end[];
++ extern char __vectors_bhb_loop8_start[], __vectors_bhb_loop8_end[];
++ void *vec_start, *vec_end;
++
++ if (system_state > SYSTEM_SCHEDULING) {
++ pr_err("CPU%u: Spectre BHB workaround too late - system vulnerable\n",
++ smp_processor_id());
++ return SPECTRE_VULNERABLE;
++ }
++
++ switch (method) {
++ case SPECTRE_V2_METHOD_LOOP8:
++ vec_start = __vectors_bhb_loop8_start;
++ vec_end = __vectors_bhb_loop8_end;
++ break;
++
++ case SPECTRE_V2_METHOD_BPIALL:
++ vec_start = __vectors_bhb_bpiall_start;
++ vec_end = __vectors_bhb_bpiall_end;
++ break;
++
++ default:
++ pr_err("CPU%u: unknown Spectre BHB state %d\n",
++ smp_processor_id(), method);
++ return SPECTRE_VULNERABLE;
++ }
++
++ copy_from_lma(vectors_page, vec_start, vec_end);
++ flush_vectors(vectors_page, 0, vec_end - vec_start);
++
++ return SPECTRE_MITIGATED;
++}
++#endif
++
+ void __init early_trap_init(void *vectors_base)
+ {
+-#ifndef CONFIG_CPU_V7M
+- unsigned long vectors = (unsigned long)vectors_base;
+ extern char __stubs_start[], __stubs_end[];
+ extern char __vectors_start[], __vectors_end[];
+ unsigned i;
+@@ -830,17 +880,20 @@ void __init early_trap_init(void *vectors_base)
+ * into the vector page, mapped at 0xffff0000, and ensure these
+ * are visible to the instruction stream.
+ */
+- memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start);
+- memcpy((void *)vectors + 0x1000, __stubs_start, __stubs_end - __stubs_start);
++ copy_from_lma(vectors_base, __vectors_start, __vectors_end);
++ copy_from_lma(vectors_base + 0x1000, __stubs_start, __stubs_end);
+
+ kuser_init(vectors_base);
+
+- flush_icache_range(vectors, vectors + PAGE_SIZE * 2);
++ flush_vectors(vectors_base, 0, PAGE_SIZE * 2);
++}
+ #else /* ifndef CONFIG_CPU_V7M */
++void __init early_trap_init(void *vectors_base)
++{
+ /*
+ * on V7-M there is no need to copy the vector table to a dedicated
+ * memory area. The address is configurable and so a table in the kernel
+ * image can be used.
+ */
+-#endif
+ }
++#endif
+diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
+index 423a97dd2f57c..c6bf34a33849c 100644
+--- a/arch/arm/mm/Kconfig
++++ b/arch/arm/mm/Kconfig
+@@ -833,6 +833,7 @@ config CPU_BPREDICT_DISABLE
+
+ config CPU_SPECTRE
+ bool
++ select GENERIC_CPU_VULNERABILITIES
+
+ config HARDEN_BRANCH_PREDICTOR
+ bool "Harden the branch predictor against aliasing attacks" if EXPERT
+@@ -853,6 +854,16 @@ config HARDEN_BRANCH_PREDICTOR
+
+ If unsure, say Y.
+
++config HARDEN_BRANCH_HISTORY
++ bool "Harden Spectre style attacks against branch history" if EXPERT
++ depends on CPU_SPECTRE
++ default y
++ help
++ Speculation attacks against some high-performance processors can
++ make use of branch history to influence future speculation. When
++ taking an exception, a sequence of branches overwrites the branch
++ history, or branch history is invalidated.
++
+ config TLS_REG_EMUL
+ bool
+ select NEED_KUSER_HELPERS
+diff --git a/arch/arm/mm/proc-v7-bugs.c b/arch/arm/mm/proc-v7-bugs.c
+index 114c05ab4dd91..06dbfb968182d 100644
+--- a/arch/arm/mm/proc-v7-bugs.c
++++ b/arch/arm/mm/proc-v7-bugs.c
+@@ -6,8 +6,35 @@
+ #include <asm/cp15.h>
+ #include <asm/cputype.h>
+ #include <asm/proc-fns.h>
++#include <asm/spectre.h>
+ #include <asm/system_misc.h>
+
++#ifdef CONFIG_ARM_PSCI
++static int __maybe_unused spectre_v2_get_cpu_fw_mitigation_state(void)
++{
++ struct arm_smccc_res res;
++
++ arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
++ ARM_SMCCC_ARCH_WORKAROUND_1, &res);
++
++ switch ((int)res.a0) {
++ case SMCCC_RET_SUCCESS:
++ return SPECTRE_MITIGATED;
++
++ case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED:
++ return SPECTRE_UNAFFECTED;
++
++ default:
++ return SPECTRE_VULNERABLE;
++ }
++}
++#else
++static int __maybe_unused spectre_v2_get_cpu_fw_mitigation_state(void)
++{
++ return SPECTRE_VULNERABLE;
++}
++#endif
++
+ #ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
+ DEFINE_PER_CPU(harden_branch_predictor_fn_t, harden_branch_predictor_fn);
+
+@@ -36,13 +63,61 @@ static void __maybe_unused call_hvc_arch_workaround_1(void)
+ arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
+ }
+
+-static void cpu_v7_spectre_init(void)
++static unsigned int spectre_v2_install_workaround(unsigned int method)
+ {
+ const char *spectre_v2_method = NULL;
+ int cpu = smp_processor_id();
+
+ if (per_cpu(harden_branch_predictor_fn, cpu))
+- return;
++ return SPECTRE_MITIGATED;
++
++ switch (method) {
++ case SPECTRE_V2_METHOD_BPIALL:
++ per_cpu(harden_branch_predictor_fn, cpu) =
++ harden_branch_predictor_bpiall;
++ spectre_v2_method = "BPIALL";
++ break;
++
++ case SPECTRE_V2_METHOD_ICIALLU:
++ per_cpu(harden_branch_predictor_fn, cpu) =
++ harden_branch_predictor_iciallu;
++ spectre_v2_method = "ICIALLU";
++ break;
++
++ case SPECTRE_V2_METHOD_HVC:
++ per_cpu(harden_branch_predictor_fn, cpu) =
++ call_hvc_arch_workaround_1;
++ cpu_do_switch_mm = cpu_v7_hvc_switch_mm;
++ spectre_v2_method = "hypervisor";
++ break;
++
++ case SPECTRE_V2_METHOD_SMC:
++ per_cpu(harden_branch_predictor_fn, cpu) =
++ call_smc_arch_workaround_1;
++ cpu_do_switch_mm = cpu_v7_smc_switch_mm;
++ spectre_v2_method = "firmware";
++ break;
++ }
++
++ if (spectre_v2_method)
++ pr_info("CPU%u: Spectre v2: using %s workaround\n",
++ smp_processor_id(), spectre_v2_method);
++
++ return SPECTRE_MITIGATED;
++}
++#else
++static unsigned int spectre_v2_install_workaround(unsigned int method)
++{
++ pr_info("CPU%u: Spectre V2: workarounds disabled by configuration\n",
++ smp_processor_id());
++
++ return SPECTRE_VULNERABLE;
++}
++#endif
++
++static void cpu_v7_spectre_v2_init(void)
++{
++ unsigned int state, method = 0;
+
+ switch (read_cpuid_part()) {
+ case ARM_CPU_PART_CORTEX_A8:
+@@ -51,69 +126,133 @@ static void cpu_v7_spectre_init(void)
+ case ARM_CPU_PART_CORTEX_A17:
+ case ARM_CPU_PART_CORTEX_A73:
+ case ARM_CPU_PART_CORTEX_A75:
+- per_cpu(harden_branch_predictor_fn, cpu) =
+- harden_branch_predictor_bpiall;
+- spectre_v2_method = "BPIALL";
++ state = SPECTRE_MITIGATED;
++ method = SPECTRE_V2_METHOD_BPIALL;
+ break;
+
+ case ARM_CPU_PART_CORTEX_A15:
+ case ARM_CPU_PART_BRAHMA_B15:
+- per_cpu(harden_branch_predictor_fn, cpu) =
+- harden_branch_predictor_iciallu;
+- spectre_v2_method = "ICIALLU";
++ state = SPECTRE_MITIGATED;
++ method = SPECTRE_V2_METHOD_ICIALLU;
+ break;
+
+-#ifdef CONFIG_ARM_PSCI
+ case ARM_CPU_PART_BRAHMA_B53:
+ /* Requires no workaround */
++ state = SPECTRE_UNAFFECTED;
+ break;
++
+ default:
+ /* Other ARM CPUs require no workaround */
+- if (read_cpuid_implementor() == ARM_CPU_IMP_ARM)
++ if (read_cpuid_implementor() == ARM_CPU_IMP_ARM) {
++ state = SPECTRE_UNAFFECTED;
+ break;
++ }
++
+ fallthrough;
+- /* Cortex A57/A72 require firmware workaround */
+- case ARM_CPU_PART_CORTEX_A57:
+- case ARM_CPU_PART_CORTEX_A72: {
+- struct arm_smccc_res res;
+
+- arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
+- ARM_SMCCC_ARCH_WORKAROUND_1, &res);
+- if ((int)res.a0 != 0)
+- return;
++ /* Cortex A57/A72 require firmware workaround */
++ case ARM_CPU_PART_CORTEX_A57:
++ case ARM_CPU_PART_CORTEX_A72:
++ state = spectre_v2_get_cpu_fw_mitigation_state();
++ if (state != SPECTRE_MITIGATED)
++ break;
+
+ switch (arm_smccc_1_1_get_conduit()) {
+ case SMCCC_CONDUIT_HVC:
+- per_cpu(harden_branch_predictor_fn, cpu) =
+- call_hvc_arch_workaround_1;
+- cpu_do_switch_mm = cpu_v7_hvc_switch_mm;
+- spectre_v2_method = "hypervisor";
++ method = SPECTRE_V2_METHOD_HVC;
+ break;
+
+ case SMCCC_CONDUIT_SMC:
+- per_cpu(harden_branch_predictor_fn, cpu) =
+- call_smc_arch_workaround_1;
+- cpu_do_switch_mm = cpu_v7_smc_switch_mm;
+- spectre_v2_method = "firmware";
++ method = SPECTRE_V2_METHOD_SMC;
+ break;
+
+ default:
++ state = SPECTRE_VULNERABLE;
+ break;
+ }
+ }
+-#endif
++
++ if (state == SPECTRE_MITIGATED)
++ state = spectre_v2_install_workaround(method);
++
++ spectre_v2_update_state(state, method);
++}
++
++#ifdef CONFIG_HARDEN_BRANCH_HISTORY
++static int spectre_bhb_method;
++
++static const char *spectre_bhb_method_name(int method)
++{
++ switch (method) {
++ case SPECTRE_V2_METHOD_LOOP8:
++ return "loop";
++
++ case SPECTRE_V2_METHOD_BPIALL:
++ return "BPIALL";
++
++ default:
++ return "unknown";
+ }
++}
+
+- if (spectre_v2_method)
+- pr_info("CPU%u: Spectre v2: using %s workaround\n",
+- smp_processor_id(), spectre_v2_method);
++static int spectre_bhb_install_workaround(int method)
++{
++ if (spectre_bhb_method != method) {
++ if (spectre_bhb_method) {
++ pr_err("CPU%u: Spectre BHB: method disagreement, system vulnerable\n",
++ smp_processor_id());
++
++ return SPECTRE_VULNERABLE;
++ }
++
++ if (spectre_bhb_update_vectors(method) == SPECTRE_VULNERABLE)
++ return SPECTRE_VULNERABLE;
++
++ spectre_bhb_method = method;
++ }
++
++ pr_info("CPU%u: Spectre BHB: using %s workaround\n",
++ smp_processor_id(), spectre_bhb_method_name(method));
++
++ return SPECTRE_MITIGATED;
+ }
+ #else
+-static void cpu_v7_spectre_init(void)
++static int spectre_bhb_install_workaround(int method)
+ {
++ return SPECTRE_VULNERABLE;
+ }
+ #endif
+
++static void cpu_v7_spectre_bhb_init(void)
++{
++ unsigned int state, method = 0;
++
++ switch (read_cpuid_part()) {
++ case ARM_CPU_PART_CORTEX_A15:
++ case ARM_CPU_PART_BRAHMA_B15:
++ case ARM_CPU_PART_CORTEX_A57:
++ case ARM_CPU_PART_CORTEX_A72:
++ state = SPECTRE_MITIGATED;
++ method = SPECTRE_V2_METHOD_LOOP8;
++ break;
++
++ case ARM_CPU_PART_CORTEX_A73:
++ case ARM_CPU_PART_CORTEX_A75:
++ state = SPECTRE_MITIGATED;
++ method = SPECTRE_V2_METHOD_BPIALL;
++ break;
++
++ default:
++ state = SPECTRE_UNAFFECTED;
++ break;
++ }
++
++ if (state == SPECTRE_MITIGATED)
++ state = spectre_bhb_install_workaround(method);
++
++ spectre_v2_update_state(state, method);
++}
++
+ static __maybe_unused bool cpu_v7_check_auxcr_set(bool *warned,
+ u32 mask, const char *msg)
+ {
+@@ -142,16 +281,17 @@ static bool check_spectre_auxcr(bool *warned, u32 bit)
+ void cpu_v7_ca8_ibe(void)
+ {
+ if (check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(6)))
+- cpu_v7_spectre_init();
++ cpu_v7_spectre_v2_init();
+ }
+
+ void cpu_v7_ca15_ibe(void)
+ {
+ if (check_spectre_auxcr(this_cpu_ptr(&spectre_warned), BIT(0)))
+- cpu_v7_spectre_init();
++ cpu_v7_spectre_v2_init();
+ }
+
+ void cpu_v7_bugs_init(void)
+ {
+- cpu_v7_spectre_init();
++ cpu_v7_spectre_v2_init();
++ cpu_v7_spectre_bhb_init();
+ }
+diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
+index 3da71fe56b922..7c7906e9dafda 100644
+--- a/arch/arm64/Kconfig
++++ b/arch/arm64/Kconfig
+@@ -1184,6 +1184,15 @@ config UNMAP_KERNEL_AT_EL0
+
+ If unsure, say Y.
+
++config MITIGATE_SPECTRE_BRANCH_HISTORY
++ bool "Mitigate Spectre style attacks against branch history" if EXPERT
++ default y
++ help
++ Speculation attacks against some high-performance processors can
++ make use of branch history to influence future speculation.
++ When taking an exception from user-space, a sequence of branches
++ or a firmware call overwrites the branch history.
++
+ config RODATA_FULL_DEFAULT_ENABLED
+ bool "Apply r/o permissions of VM areas also to their linear aliases"
+ default y
+diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
+index ddbe6bf00e336..011e681a23366 100644
+--- a/arch/arm64/include/asm/assembler.h
++++ b/arch/arm64/include/asm/assembler.h
+@@ -97,6 +97,13 @@
+ hint #20
+ .endm
+
++/*
++ * Clear Branch History instruction
++ */
++ .macro clearbhb
++ hint #22
++ .endm
++
+ /*
+ * Speculation barrier
+ */
+@@ -795,4 +802,30 @@ USER(\label, ic ivau, \tmp2) // invalidate I line PoU
+
+ #endif /* GNU_PROPERTY_AARCH64_FEATURE_1_DEFAULT */
+
++ .macro __mitigate_spectre_bhb_loop tmp
++#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++alternative_cb spectre_bhb_patch_loop_iter
++ mov \tmp, #32 // Patched to correct the immediate
++alternative_cb_end
++.Lspectre_bhb_loop\@:
++ b . + 4
++ subs \tmp, \tmp, #1
++ b.ne .Lspectre_bhb_loop\@
++ sb
++#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++ .endm
++
++ /* Save/restores x0-x3 to the stack */
++ .macro __mitigate_spectre_bhb_fw
++#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++ stp x0, x1, [sp, #-16]!
++ stp x2, x3, [sp, #-16]!
++ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3
++alternative_cb smccc_patch_fw_mitigation_conduit
++ nop // Patched to SMC/HVC #0
++alternative_cb_end
++ ldp x2, x3, [sp], #16
++ ldp x0, x1, [sp], #16
++#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++ .endm
+ #endif /* __ASM_ASSEMBLER_H */
+diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h
+index 7faae6ff3ab4d..24ed6643da266 100644
+--- a/arch/arm64/include/asm/cpu.h
++++ b/arch/arm64/include/asm/cpu.h
+@@ -25,6 +25,7 @@ struct cpuinfo_arm64 {
+ u64 reg_id_aa64dfr1;
+ u64 reg_id_aa64isar0;
+ u64 reg_id_aa64isar1;
++ u64 reg_id_aa64isar2;
+ u64 reg_id_aa64mmfr0;
+ u64 reg_id_aa64mmfr1;
+ u64 reg_id_aa64mmfr2;
+diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h
+index e7d98997c09c3..f42fd0a2e81c8 100644
+--- a/arch/arm64/include/asm/cpucaps.h
++++ b/arch/arm64/include/asm/cpucaps.h
+@@ -66,7 +66,8 @@
+ #define ARM64_HAS_TLB_RANGE 56
+ #define ARM64_MTE 57
+ #define ARM64_WORKAROUND_1508412 58
++#define ARM64_SPECTRE_BHB 59
+
+-#define ARM64_NCAPS 59
++#define ARM64_NCAPS 60
+
+ #endif /* __ASM_CPUCAPS_H */
+diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
+index da250e4741bd7..423f9b40e4d95 100644
+--- a/arch/arm64/include/asm/cpufeature.h
++++ b/arch/arm64/include/asm/cpufeature.h
+@@ -606,6 +606,34 @@ static inline bool cpu_supports_mixed_endian_el0(void)
+ return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
+ }
+
++static inline bool supports_csv2p3(int scope)
++{
++ u64 pfr0;
++ u8 csv2_val;
++
++ if (scope == SCOPE_LOCAL_CPU)
++ pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1);
++ else
++ pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
++
++ csv2_val = cpuid_feature_extract_unsigned_field(pfr0,
++ ID_AA64PFR0_CSV2_SHIFT);
++ return csv2_val == 3;
++}
++
++static inline bool supports_clearbhb(int scope)
++{
++ u64 isar2;
++
++ if (scope == SCOPE_LOCAL_CPU)
++ isar2 = read_sysreg_s(SYS_ID_AA64ISAR2_EL1);
++ else
++ isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
++
++ return cpuid_feature_extract_unsigned_field(isar2,
++ ID_AA64ISAR2_CLEARBHB_SHIFT);
++}
++
+ static inline bool system_supports_32bit_el0(void)
+ {
+ return cpus_have_const_cap(ARM64_HAS_32BIT_EL0);
+diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h
+index ef5b040dee44d..bfbf0c4c7c5e5 100644
+--- a/arch/arm64/include/asm/cputype.h
++++ b/arch/arm64/include/asm/cputype.h
+@@ -59,6 +59,7 @@
+ #define ARM_CPU_IMP_NVIDIA 0x4E
+ #define ARM_CPU_IMP_FUJITSU 0x46
+ #define ARM_CPU_IMP_HISI 0x48
++#define ARM_CPU_IMP_APPLE 0x61
+
+ #define ARM_CPU_PART_AEM_V8 0xD0F
+ #define ARM_CPU_PART_FOUNDATION 0xD00
+@@ -72,6 +73,14 @@
+ #define ARM_CPU_PART_CORTEX_A76 0xD0B
+ #define ARM_CPU_PART_NEOVERSE_N1 0xD0C
+ #define ARM_CPU_PART_CORTEX_A77 0xD0D
++#define ARM_CPU_PART_NEOVERSE_V1 0xD40
++#define ARM_CPU_PART_CORTEX_A78 0xD41
++#define ARM_CPU_PART_CORTEX_X1 0xD44
++#define ARM_CPU_PART_CORTEX_A510 0xD46
++#define ARM_CPU_PART_CORTEX_A710 0xD47
++#define ARM_CPU_PART_CORTEX_X2 0xD48
++#define ARM_CPU_PART_NEOVERSE_N2 0xD49
++#define ARM_CPU_PART_CORTEX_A78C 0xD4B
+
+ #define APM_CPU_PART_POTENZA 0x000
+
+@@ -99,6 +108,9 @@
+
+ #define HISI_CPU_PART_TSV110 0xD01
+
++#define APPLE_CPU_PART_M1_ICESTORM 0x022
++#define APPLE_CPU_PART_M1_FIRESTORM 0x023
++
+ #define MIDR_CORTEX_A53 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53)
+ #define MIDR_CORTEX_A57 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A57)
+ #define MIDR_CORTEX_A72 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A72)
+@@ -109,6 +121,14 @@
+ #define MIDR_CORTEX_A76 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76)
+ #define MIDR_NEOVERSE_N1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N1)
+ #define MIDR_CORTEX_A77 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A77)
++#define MIDR_NEOVERSE_V1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_V1)
++#define MIDR_CORTEX_A78 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78)
++#define MIDR_CORTEX_X1 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X1)
++#define MIDR_CORTEX_A510 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A510)
++#define MIDR_CORTEX_A710 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A710)
++#define MIDR_CORTEX_X2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_X2)
++#define MIDR_NEOVERSE_N2 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_NEOVERSE_N2)
++#define MIDR_CORTEX_A78C MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A78C)
+ #define MIDR_THUNDERX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX)
+ #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX)
+ #define MIDR_THUNDERX_83XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_83XX)
+@@ -127,6 +147,8 @@
+ #define MIDR_NVIDIA_CARMEL MIDR_CPU_MODEL(ARM_CPU_IMP_NVIDIA, NVIDIA_CPU_PART_CARMEL)
+ #define MIDR_FUJITSU_A64FX MIDR_CPU_MODEL(ARM_CPU_IMP_FUJITSU, FUJITSU_CPU_PART_A64FX)
+ #define MIDR_HISI_TSV110 MIDR_CPU_MODEL(ARM_CPU_IMP_HISI, HISI_CPU_PART_TSV110)
++#define MIDR_APPLE_M1_ICESTORM MIDR_CPU_MODEL(ARM_CPU_IMP_APPLE, APPLE_CPU_PART_M1_ICESTORM)
++#define MIDR_APPLE_M1_FIRESTORM MIDR_CPU_MODEL(ARM_CPU_IMP_APPLE, APPLE_CPU_PART_M1_FIRESTORM)
+
+ /* Fujitsu Erratum 010001 affects A64FX 1.0 and 1.1, (v0r0 and v1r0) */
+ #define MIDR_FUJITSU_ERRATUM_010001 MIDR_FUJITSU_A64FX
+diff --git a/arch/arm64/include/asm/fixmap.h b/arch/arm64/include/asm/fixmap.h
+index 4335800201c97..daff882883f92 100644
+--- a/arch/arm64/include/asm/fixmap.h
++++ b/arch/arm64/include/asm/fixmap.h
+@@ -62,9 +62,11 @@ enum fixed_addresses {
+ #endif /* CONFIG_ACPI_APEI_GHES */
+
+ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
++ FIX_ENTRY_TRAMP_TEXT3,
++ FIX_ENTRY_TRAMP_TEXT2,
++ FIX_ENTRY_TRAMP_TEXT1,
+ FIX_ENTRY_TRAMP_DATA,
+- FIX_ENTRY_TRAMP_TEXT,
+-#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT))
++#define TRAMP_VALIAS (__fix_to_virt(FIX_ENTRY_TRAMP_TEXT1))
+ #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
+ __end_of_permanent_fixed_addresses,
+
+diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
+index 9a5498c2c8eea..6422147ea612f 100644
+--- a/arch/arm64/include/asm/hwcap.h
++++ b/arch/arm64/include/asm/hwcap.h
+@@ -105,6 +105,9 @@
+ #define KERNEL_HWCAP_RNG __khwcap2_feature(RNG)
+ #define KERNEL_HWCAP_BTI __khwcap2_feature(BTI)
+ #define KERNEL_HWCAP_MTE __khwcap2_feature(MTE)
++#define KERNEL_HWCAP_ECV __khwcap2_feature(ECV)
++#define KERNEL_HWCAP_AFP __khwcap2_feature(AFP)
++#define KERNEL_HWCAP_RPRES __khwcap2_feature(RPRES)
+
+ /*
+ * This yields a mask that user programs can use to figure out what
+diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
+index 4b39293d0f72d..d45b42295254d 100644
+--- a/arch/arm64/include/asm/insn.h
++++ b/arch/arm64/include/asm/insn.h
+@@ -65,6 +65,7 @@ enum aarch64_insn_hint_cr_op {
+ AARCH64_INSN_HINT_PSB = 0x11 << 5,
+ AARCH64_INSN_HINT_TSB = 0x12 << 5,
+ AARCH64_INSN_HINT_CSDB = 0x14 << 5,
++ AARCH64_INSN_HINT_CLEARBHB = 0x16 << 5,
+
+ AARCH64_INSN_HINT_BTI = 0x20 << 5,
+ AARCH64_INSN_HINT_BTIC = 0x22 << 5,
+diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
+index 044bb9e2cd74f..ada24a20a5671 100644
+--- a/arch/arm64/include/asm/kvm_asm.h
++++ b/arch/arm64/include/asm/kvm_asm.h
+@@ -35,6 +35,9 @@
+ #define KVM_VECTOR_PREAMBLE (2 * AARCH64_INSN_SIZE)
+
+ #define __SMCCC_WORKAROUND_1_SMC_SZ 36
++#define __SMCCC_WORKAROUND_3_SMC_SZ 36
++#define __SPECTRE_BHB_LOOP_SZ 44
++#define __SPECTRE_BHB_CLEARBHB_SZ 12
+
+ #define KVM_HOST_SMCCC_ID(id) \
+ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
+@@ -199,6 +202,11 @@ extern void __vgic_v3_init_lrs(void);
+ extern u32 __kvm_get_mdcr_el2(void);
+
+ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ];
++extern char __smccc_workaround_3_smc[__SMCCC_WORKAROUND_3_SMC_SZ];
++extern char __spectre_bhb_loop_k8[__SPECTRE_BHB_LOOP_SZ];
++extern char __spectre_bhb_loop_k24[__SPECTRE_BHB_LOOP_SZ];
++extern char __spectre_bhb_loop_k32[__SPECTRE_BHB_LOOP_SZ];
++extern char __spectre_bhb_clearbhb[__SPECTRE_BHB_LOOP_SZ];
+
+ /*
+ * Obtain the PC-relative address of a kernel symbol
+diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
+index 331394306ccee..47dafd6ab3a30 100644
+--- a/arch/arm64/include/asm/kvm_mmu.h
++++ b/arch/arm64/include/asm/kvm_mmu.h
+@@ -237,7 +237,8 @@ static inline void *kvm_get_hyp_vector(void)
+ void *vect = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector));
+ int slot = -1;
+
+- if (cpus_have_const_cap(ARM64_SPECTRE_V2) && data->fn) {
++ if ((cpus_have_const_cap(ARM64_SPECTRE_V2) ||
++ cpus_have_const_cap(ARM64_SPECTRE_BHB)) && data->template_start) {
+ vect = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs));
+ slot = data->hyp_vectors_slot;
+ }
+diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
+index c7315862e2435..bc151b7dc042c 100644
+--- a/arch/arm64/include/asm/mmu.h
++++ b/arch/arm64/include/asm/mmu.h
+@@ -67,6 +67,12 @@ typedef void (*bp_hardening_cb_t)(void);
+ struct bp_hardening_data {
+ int hyp_vectors_slot;
+ bp_hardening_cb_t fn;
++
++ /*
++ * template_start is only used by the BHB mitigation to identify the
++ * hyp_vectors_slot sequence.
++ */
++ const char *template_start;
+ };
+
+ DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
+diff --git a/arch/arm64/include/asm/sections.h b/arch/arm64/include/asm/sections.h
+index 3994169985efc..6a45c26da46e3 100644
+--- a/arch/arm64/include/asm/sections.h
++++ b/arch/arm64/include/asm/sections.h
+@@ -19,4 +19,9 @@ extern char __irqentry_text_start[], __irqentry_text_end[];
+ extern char __mmuoff_data_start[], __mmuoff_data_end[];
+ extern char __entry_tramp_text_start[], __entry_tramp_text_end[];
+
++static inline size_t entry_tramp_text_size(void)
++{
++ return __entry_tramp_text_end - __entry_tramp_text_start;
++}
++
+ #endif /* __ASM_SECTIONS_H */
+diff --git a/arch/arm64/include/asm/spectre.h b/arch/arm64/include/asm/spectre.h
+index fcdfbce302bdf..4b3a5f050f71f 100644
+--- a/arch/arm64/include/asm/spectre.h
++++ b/arch/arm64/include/asm/spectre.h
+@@ -29,4 +29,8 @@ bool has_spectre_v4(const struct arm64_cpu_capabilities *cap, int scope);
+ void spectre_v4_enable_mitigation(const struct arm64_cpu_capabilities *__unused);
+ void spectre_v4_enable_task_mitigation(struct task_struct *tsk);
+
++enum mitigation_state arm64_get_spectre_bhb_state(void);
++bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry, int scope);
++u8 spectre_bhb_loop_affected(int scope);
++void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *__unused);
+ #endif /* __ASM_SPECTRE_H */
+diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
+index 801861d054268..1f2209ad2cca1 100644
+--- a/arch/arm64/include/asm/sysreg.h
++++ b/arch/arm64/include/asm/sysreg.h
+@@ -175,6 +175,7 @@
+
+ #define SYS_ID_AA64ISAR0_EL1 sys_reg(3, 0, 0, 6, 0)
+ #define SYS_ID_AA64ISAR1_EL1 sys_reg(3, 0, 0, 6, 1)
++#define SYS_ID_AA64ISAR2_EL1 sys_reg(3, 0, 0, 6, 2)
+
+ #define SYS_ID_AA64MMFR0_EL1 sys_reg(3, 0, 0, 7, 0)
+ #define SYS_ID_AA64MMFR1_EL1 sys_reg(3, 0, 0, 7, 1)
+@@ -687,6 +688,21 @@
+ #define ID_AA64ISAR1_GPI_NI 0x0
+ #define ID_AA64ISAR1_GPI_IMP_DEF 0x1
+
++/* id_aa64isar2 */
++#define ID_AA64ISAR2_CLEARBHB_SHIFT 28
++#define ID_AA64ISAR2_RPRES_SHIFT 4
++#define ID_AA64ISAR2_WFXT_SHIFT 0
++
++#define ID_AA64ISAR2_RPRES_8BIT 0x0
++#define ID_AA64ISAR2_RPRES_12BIT 0x1
++/*
++ * Value 0x1 has been removed from the architecture, and is
++ * reserved, but has not yet been removed from the ARM ARM
++ * as of ARM DDI 0487G.b.
++ */
++#define ID_AA64ISAR2_WFXT_NI 0x0
++#define ID_AA64ISAR2_WFXT_SUPPORTED 0x2
++
+ /* id_aa64pfr0 */
+ #define ID_AA64PFR0_CSV3_SHIFT 60
+ #define ID_AA64PFR0_CSV2_SHIFT 56
+@@ -786,6 +802,8 @@
+ #endif
+
+ /* id_aa64mmfr1 */
++#define ID_AA64MMFR1_ECBHB_SHIFT 60
++#define ID_AA64MMFR1_AFP_SHIFT 44
+ #define ID_AA64MMFR1_ETS_SHIFT 36
+ #define ID_AA64MMFR1_TWED_SHIFT 32
+ #define ID_AA64MMFR1_XNX_SHIFT 28
+diff --git a/arch/arm64/include/asm/vectors.h b/arch/arm64/include/asm/vectors.h
+new file mode 100644
+index 0000000000000..f64613a96d530
+--- /dev/null
++++ b/arch/arm64/include/asm/vectors.h
+@@ -0,0 +1,73 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++/*
++ * Copyright (C) 2022 ARM Ltd.
++ */
++#ifndef __ASM_VECTORS_H
++#define __ASM_VECTORS_H
++
++#include <linux/bug.h>
++#include <linux/percpu.h>
++
++#include <asm/fixmap.h>
++
++extern char vectors[];
++extern char tramp_vectors[];
++extern char __bp_harden_el1_vectors[];
++
++/*
++ * Note: the order of this enum corresponds to two arrays in entry.S:
++ * tramp_vecs and __bp_harden_el1_vectors. By default the canonical
++ * 'full fat' vectors are used directly.
++ */
++enum arm64_bp_harden_el1_vectors {
++#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++ /*
++ * Perform the BHB loop mitigation, before branching to the canonical
++ * vectors.
++ */
++ EL1_VECTOR_BHB_LOOP,
++
++ /*
++ * Make the SMC call for firmware mitigation, before branching to the
++ * canonical vectors.
++ */
++ EL1_VECTOR_BHB_FW,
++
++ /*
++ * Use the ClearBHB instruction, before branching to the canonical
++ * vectors.
++ */
++ EL1_VECTOR_BHB_CLEAR_INSN,
++#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++
++ /*
++ * Remap the kernel before branching to the canonical vectors.
++ */
++ EL1_VECTOR_KPTI,
++};
++
++#ifndef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++#define EL1_VECTOR_BHB_LOOP -1
++#define EL1_VECTOR_BHB_FW -1
++#define EL1_VECTOR_BHB_CLEAR_INSN -1
++#endif /* !CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++
++/* The vectors to use on return from EL0. e.g. to remap the kernel */
++DECLARE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector);
++
++#ifndef CONFIG_UNMAP_KERNEL_AT_EL0
++#define TRAMP_VALIAS 0
++#endif
++
++static inline const char *
++arm64_get_bp_hardening_vector(enum arm64_bp_harden_el1_vectors slot)
++{
++ if (arm64_kernel_unmapped_at_el0())
++ return (char *)TRAMP_VALIAS + SZ_2K * slot;
++
++ WARN_ON_ONCE(slot == EL1_VECTOR_KPTI);
++
++ return __bp_harden_el1_vectors + SZ_2K * slot;
++}
++
++#endif /* __ASM_VECTORS_H */
+diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
+index b8f41aa234ee1..f03731847d9df 100644
+--- a/arch/arm64/include/uapi/asm/hwcap.h
++++ b/arch/arm64/include/uapi/asm/hwcap.h
+@@ -75,5 +75,8 @@
+ #define HWCAP2_RNG (1 << 16)
+ #define HWCAP2_BTI (1 << 17)
+ #define HWCAP2_MTE (1 << 18)
++#define HWCAP2_ECV (1 << 19)
++#define HWCAP2_AFP (1 << 20)
++#define HWCAP2_RPRES (1 << 21)
+
+ #endif /* _UAPI__ASM_HWCAP_H */
+diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
+index 1c17c3a24411d..531ff62e82e95 100644
+--- a/arch/arm64/include/uapi/asm/kvm.h
++++ b/arch/arm64/include/uapi/asm/kvm.h
+@@ -273,6 +273,11 @@ struct kvm_vcpu_events {
+ #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED 3
+ #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED (1U << 4)
+
++#define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3 KVM_REG_ARM_FW_REG(3)
++#define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_AVAIL 0
++#define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_AVAIL 1
++#define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_REQUIRED 2
++
+ /* SVE registers */
+ #define KVM_REG_ARM64_SVE (0x15 << KVM_REG_ARM_COPROC_SHIFT)
+
+diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
+index cafaf0da05b7c..533559c7d2b31 100644
+--- a/arch/arm64/kernel/cpu_errata.c
++++ b/arch/arm64/kernel/cpu_errata.c
+@@ -473,6 +473,13 @@ const struct arm64_cpu_capabilities arm64_errata[] = {
+ .matches = has_spectre_v4,
+ .cpu_enable = spectre_v4_enable_mitigation,
+ },
++ {
++ .desc = "Spectre-BHB",
++ .capability = ARM64_SPECTRE_BHB,
++ .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM,
++ .matches = is_spectre_bhb_affected,
++ .cpu_enable = spectre_bhb_enable_mitigation,
++ },
+ #ifdef CONFIG_ARM64_ERRATUM_1418040
+ {
+ .desc = "ARM erratum 1418040",
+diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
+index 5001c43ea6c33..c9108ed406458 100644
+--- a/arch/arm64/kernel/cpufeature.c
++++ b/arch/arm64/kernel/cpufeature.c
+@@ -65,11 +65,13 @@
+ #include <linux/bsearch.h>
+ #include <linux/cpumask.h>
+ #include <linux/crash_dump.h>
++#include <linux/percpu.h>
+ #include <linux/sort.h>
+ #include <linux/stop_machine.h>
+ #include <linux/types.h>
+ #include <linux/mm.h>
+ #include <linux/cpu.h>
++
+ #include <asm/cpu.h>
+ #include <asm/cpufeature.h>
+ #include <asm/cpu_ops.h>
+@@ -79,6 +81,7 @@
+ #include <asm/processor.h>
+ #include <asm/sysreg.h>
+ #include <asm/traps.h>
++#include <asm/vectors.h>
+ #include <asm/virt.h>
+
+ /* Kernel representation of AT_HWCAP and AT_HWCAP2 */
+@@ -104,6 +107,8 @@ DECLARE_BITMAP(boot_capabilities, ARM64_NPATCHABLE);
+ bool arm64_use_ng_mappings = false;
+ EXPORT_SYMBOL(arm64_use_ng_mappings);
+
++DEFINE_PER_CPU_READ_MOSTLY(const char *, this_cpu_vector) = vectors;
++
+ /*
+ * Flag to indicate if we have computed the system wide
+ * capabilities based on the boot time active CPUs. This
+@@ -205,6 +210,12 @@ static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
+ ARM64_FTR_END,
+ };
+
++static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
++ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_CLEARBHB_SHIFT, 4, 0),
++ ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_RPRES_SHIFT, 4, 0),
++ ARM64_FTR_END,
++};
++
+ static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = {
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV3_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR0_CSV2_SHIFT, 4, 0),
+@@ -259,7 +270,7 @@ static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
+ };
+
+ static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
+- ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
++ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_ECV_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_FGT_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR0_EXS_SHIFT, 4, 0),
+ /*
+@@ -305,6 +316,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr0[] = {
+ };
+
+ static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
++ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_AFP_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_ETS_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_TWED_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR1_XNX_SHIFT, 4, 0),
+@@ -596,6 +608,7 @@ static const struct __ftr_reg_entry {
+ /* Op1 = 0, CRn = 0, CRm = 6 */
+ ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0),
+ ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1),
++ ARM64_FTR_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2),
+
+ /* Op1 = 0, CRn = 0, CRm = 7 */
+ ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0),
+@@ -830,6 +843,7 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
+ init_cpu_ftr_reg(SYS_ID_AA64DFR1_EL1, info->reg_id_aa64dfr1);
+ init_cpu_ftr_reg(SYS_ID_AA64ISAR0_EL1, info->reg_id_aa64isar0);
+ init_cpu_ftr_reg(SYS_ID_AA64ISAR1_EL1, info->reg_id_aa64isar1);
++ init_cpu_ftr_reg(SYS_ID_AA64ISAR2_EL1, info->reg_id_aa64isar2);
+ init_cpu_ftr_reg(SYS_ID_AA64MMFR0_EL1, info->reg_id_aa64mmfr0);
+ init_cpu_ftr_reg(SYS_ID_AA64MMFR1_EL1, info->reg_id_aa64mmfr1);
+ init_cpu_ftr_reg(SYS_ID_AA64MMFR2_EL1, info->reg_id_aa64mmfr2);
+@@ -1058,6 +1072,8 @@ void update_cpu_features(int cpu,
+ info->reg_id_aa64isar0, boot->reg_id_aa64isar0);
+ taint |= check_update_ftr_reg(SYS_ID_AA64ISAR1_EL1, cpu,
+ info->reg_id_aa64isar1, boot->reg_id_aa64isar1);
++ taint |= check_update_ftr_reg(SYS_ID_AA64ISAR2_EL1, cpu,
++ info->reg_id_aa64isar2, boot->reg_id_aa64isar2);
+
+ /*
+ * Differing PARange support is fine as long as all peripherals and
+@@ -1157,6 +1173,7 @@ static u64 __read_sysreg_by_encoding(u32 sys_id)
+ read_sysreg_case(SYS_ID_AA64MMFR2_EL1);
+ read_sysreg_case(SYS_ID_AA64ISAR0_EL1);
+ read_sysreg_case(SYS_ID_AA64ISAR1_EL1);
++ read_sysreg_case(SYS_ID_AA64ISAR2_EL1);
+
+ read_sysreg_case(SYS_CNTFRQ_EL0);
+ read_sysreg_case(SYS_CTR_EL0);
+@@ -1402,6 +1419,12 @@ kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused)
+
+ int cpu = smp_processor_id();
+
++ if (__this_cpu_read(this_cpu_vector) == vectors) {
++ const char *v = arm64_get_bp_hardening_vector(EL1_VECTOR_KPTI);
++
++ __this_cpu_write(this_cpu_vector, v);
++ }
++
+ /*
+ * We don't need to rewrite the page-tables if either we've done
+ * it already or we have KASLR enabled and therefore have not
+@@ -2252,6 +2275,9 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
+ #ifdef CONFIG_ARM64_MTE
+ HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_MTE_SHIFT, FTR_UNSIGNED, ID_AA64PFR1_MTE, CAP_HWCAP, KERNEL_HWCAP_MTE),
+ #endif /* CONFIG_ARM64_MTE */
++ HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_ECV_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV),
++ HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_AFP_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP),
++ HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_RPRES_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES),
+ {},
+ };
+
+diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
+index 77605aec25fec..4c0e72781f31b 100644
+--- a/arch/arm64/kernel/cpuinfo.c
++++ b/arch/arm64/kernel/cpuinfo.c
+@@ -94,6 +94,9 @@ static const char *const hwcap_str[] = {
+ [KERNEL_HWCAP_RNG] = "rng",
+ [KERNEL_HWCAP_BTI] = "bti",
+ [KERNEL_HWCAP_MTE] = "mte",
++ [KERNEL_HWCAP_ECV] = "ecv",
++ [KERNEL_HWCAP_AFP] = "afp",
++ [KERNEL_HWCAP_RPRES] = "rpres",
+ };
+
+ #ifdef CONFIG_COMPAT
+@@ -364,6 +367,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
+ info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1);
+ info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1);
+ info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1);
++ info->reg_id_aa64isar2 = read_cpuid(ID_AA64ISAR2_EL1);
+ info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
+ info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
+ info->reg_id_aa64mmfr2 = read_cpuid(ID_AA64MMFR2_EL1);
+diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
+index fe83d6d67ec3d..d5bc1dbdd2fda 100644
+--- a/arch/arm64/kernel/entry.S
++++ b/arch/arm64/kernel/entry.S
+@@ -62,18 +62,21 @@
+
+ .macro kernel_ventry, el, label, regsize = 64
+ .align 7
+-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
++.Lventry_start\@:
+ .if \el == 0
+-alternative_if ARM64_UNMAP_KERNEL_AT_EL0
++ /*
++ * This must be the first instruction of the EL0 vector entries. It is
++ * skipped by the trampoline vectors, to trigger the cleanup.
++ */
++ b .Lskip_tramp_vectors_cleanup\@
+ .if \regsize == 64
+ mrs x30, tpidrro_el0
+ msr tpidrro_el0, xzr
+ .else
+ mov x30, xzr
+ .endif
+-alternative_else_nop_endif
++.Lskip_tramp_vectors_cleanup\@:
+ .endif
+-#endif
+
+ sub sp, sp, #S_FRAME_SIZE
+ #ifdef CONFIG_VMAP_STACK
+@@ -120,11 +123,15 @@ alternative_else_nop_endif
+ mrs x0, tpidrro_el0
+ #endif
+ b el\()\el\()_\label
++.org .Lventry_start\@ + 128 // Did we overflow the ventry slot?
+ .endm
+
+- .macro tramp_alias, dst, sym
++ .macro tramp_alias, dst, sym, tmp
+ mov_q \dst, TRAMP_VALIAS
+- add \dst, \dst, #(\sym - .entry.tramp.text)
++ adr_l \tmp, \sym
++ add \dst, \dst, \tmp
++ adr_l \tmp, .entry.tramp.text
++ sub \dst, \dst, \tmp
+ .endm
+
+ /*
+@@ -141,7 +148,7 @@ alternative_cb_end
+ tbnz \tmp2, #TIF_SSBD, .L__asm_ssbd_skip\@
+ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2
+ mov w1, #\state
+-alternative_cb spectre_v4_patch_fw_mitigation_conduit
++alternative_cb smccc_patch_fw_mitigation_conduit
+ nop // Patched to SMC/HVC #0
+ alternative_cb_end
+ .L__asm_ssbd_skip\@:
+@@ -351,21 +358,26 @@ alternative_else_nop_endif
+ ldp x24, x25, [sp, #16 * 12]
+ ldp x26, x27, [sp, #16 * 13]
+ ldp x28, x29, [sp, #16 * 14]
+- ldr lr, [sp, #S_LR]
+- add sp, sp, #S_FRAME_SIZE // restore sp
+
+ .if \el == 0
+-alternative_insn eret, nop, ARM64_UNMAP_KERNEL_AT_EL0
++alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0
++ ldr lr, [sp, #S_LR]
++ add sp, sp, #S_FRAME_SIZE // restore sp
++ eret
++alternative_else_nop_endif
+ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+ bne 4f
+- msr far_el1, x30
+- tramp_alias x30, tramp_exit_native
++ msr far_el1, x29
++ tramp_alias x30, tramp_exit_native, x29
+ br x30
+ 4:
+- tramp_alias x30, tramp_exit_compat
++ tramp_alias x30, tramp_exit_compat, x29
+ br x30
+ #endif
+ .else
++ ldr lr, [sp, #S_LR]
++ add sp, sp, #S_FRAME_SIZE // restore sp
++
+ /* Ensure any device/NC reads complete */
+ alternative_insn nop, "dmb sy", ARM64_WORKAROUND_1508412
+
+@@ -764,12 +776,6 @@ SYM_CODE_END(ret_to_user)
+
+ .popsection // .entry.text
+
+-#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+-/*
+- * Exception vectors trampoline.
+- */
+- .pushsection ".entry.tramp.text", "ax"
+-
+ // Move from tramp_pg_dir to swapper_pg_dir
+ .macro tramp_map_kernel, tmp
+ mrs \tmp, ttbr1_el1
+@@ -803,12 +809,47 @@ alternative_else_nop_endif
+ */
+ .endm
+
+- .macro tramp_ventry, regsize = 64
++ .macro tramp_data_page dst
++ adr_l \dst, .entry.tramp.text
++ sub \dst, \dst, PAGE_SIZE
++ .endm
++
++ .macro tramp_data_read_var dst, var
++#ifdef CONFIG_RANDOMIZE_BASE
++ tramp_data_page \dst
++ add \dst, \dst, #:lo12:__entry_tramp_data_\var
++ ldr \dst, [\dst]
++#else
++ ldr \dst, =\var
++#endif
++ .endm
++
++#define BHB_MITIGATION_NONE 0
++#define BHB_MITIGATION_LOOP 1
++#define BHB_MITIGATION_FW 2
++#define BHB_MITIGATION_INSN 3
++
++ .macro tramp_ventry, vector_start, regsize, kpti, bhb
+ .align 7
+ 1:
+ .if \regsize == 64
+ msr tpidrro_el0, x30 // Restored in kernel_ventry
+ .endif
++
++ .if \bhb == BHB_MITIGATION_LOOP
++ /*
++ * This sequence must appear before the first indirect branch. i.e. the
++ * ret out of tramp_ventry. It appears here because x30 is free.
++ */
++ __mitigate_spectre_bhb_loop x30
++ .endif // \bhb == BHB_MITIGATION_LOOP
++
++ .if \bhb == BHB_MITIGATION_INSN
++ clearbhb
++ isb
++ .endif // \bhb == BHB_MITIGATION_INSN
++
++ .if \kpti == 1
+ /*
+ * Defend against branch aliasing attacks by pushing a dummy
+ * entry onto the return stack and using a RET instruction to
+@@ -818,46 +859,75 @@ alternative_else_nop_endif
+ b .
+ 2:
+ tramp_map_kernel x30
+-#ifdef CONFIG_RANDOMIZE_BASE
+- adr x30, tramp_vectors + PAGE_SIZE
+ alternative_insn isb, nop, ARM64_WORKAROUND_QCOM_FALKOR_E1003
+- ldr x30, [x30]
+-#else
+- ldr x30, =vectors
+-#endif
++ tramp_data_read_var x30, vectors
+ alternative_if_not ARM64_WORKAROUND_CAVIUM_TX2_219_PRFM
+- prfm plil1strm, [x30, #(1b - tramp_vectors)]
++ prfm plil1strm, [x30, #(1b - \vector_start)]
+ alternative_else_nop_endif
++
+ msr vbar_el1, x30
+- add x30, x30, #(1b - tramp_vectors)
+ isb
++ .else
++ ldr x30, =vectors
++ .endif // \kpti == 1
++
++ .if \bhb == BHB_MITIGATION_FW
++ /*
++ * The firmware sequence must appear before the first indirect branch.
++ * i.e. the ret out of tramp_ventry. But it also needs the stack to be
++ * mapped to save/restore the registers the SMC clobbers.
++ */
++ __mitigate_spectre_bhb_fw
++ .endif // \bhb == BHB_MITIGATION_FW
++
++ add x30, x30, #(1b - \vector_start + 4)
+ ret
++.org 1b + 128 // Did we overflow the ventry slot?
+ .endm
+
+ .macro tramp_exit, regsize = 64
+- adr x30, tramp_vectors
++ tramp_data_read_var x30, this_cpu_vector
++ this_cpu_offset x29
++ ldr x30, [x30, x29]
++
+ msr vbar_el1, x30
+- tramp_unmap_kernel x30
++ ldr lr, [sp, #S_LR]
++ tramp_unmap_kernel x29
+ .if \regsize == 64
+- mrs x30, far_el1
++ mrs x29, far_el1
+ .endif
++ add sp, sp, #S_FRAME_SIZE // restore sp
+ eret
+ sb
+ .endm
+
+- .align 11
+-SYM_CODE_START_NOALIGN(tramp_vectors)
++ .macro generate_tramp_vector, kpti, bhb
++.Lvector_start\@:
+ .space 0x400
+
+- tramp_ventry
+- tramp_ventry
+- tramp_ventry
+- tramp_ventry
++ .rept 4
++ tramp_ventry .Lvector_start\@, 64, \kpti, \bhb
++ .endr
++ .rept 4
++ tramp_ventry .Lvector_start\@, 32, \kpti, \bhb
++ .endr
++ .endm
+
+- tramp_ventry 32
+- tramp_ventry 32
+- tramp_ventry 32
+- tramp_ventry 32
++#ifdef CONFIG_UNMAP_KERNEL_AT_EL0
++/*
++ * Exception vectors trampoline.
++ * The order must match __bp_harden_el1_vectors and the
++ * arm64_bp_harden_el1_vectors enum.
++ */
++ .pushsection ".entry.tramp.text", "ax"
++ .align 11
++SYM_CODE_START_NOALIGN(tramp_vectors)
++#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++ generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_LOOP
++ generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_FW
++ generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_INSN
++#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++ generate_tramp_vector kpti=1, bhb=BHB_MITIGATION_NONE
+ SYM_CODE_END(tramp_vectors)
+
+ SYM_CODE_START(tramp_exit_native)
+@@ -874,12 +944,56 @@ SYM_CODE_END(tramp_exit_compat)
+ .pushsection ".rodata", "a"
+ .align PAGE_SHIFT
+ SYM_DATA_START(__entry_tramp_data_start)
++__entry_tramp_data_vectors:
+ .quad vectors
++#ifdef CONFIG_ARM_SDE_INTERFACE
++__entry_tramp_data___sdei_asm_handler:
++ .quad __sdei_asm_handler
++#endif /* CONFIG_ARM_SDE_INTERFACE */
++__entry_tramp_data_this_cpu_vector:
++ .quad this_cpu_vector
+ SYM_DATA_END(__entry_tramp_data_start)
+ .popsection // .rodata
+ #endif /* CONFIG_RANDOMIZE_BASE */
+ #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
+
++/*
++ * Exception vectors for spectre mitigations on entry from EL1 when
++ * kpti is not in use.
++ */
++ .macro generate_el1_vector, bhb
++.Lvector_start\@:
++ kernel_ventry 1, sync_invalid // Synchronous EL1t
++ kernel_ventry 1, irq_invalid // IRQ EL1t
++ kernel_ventry 1, fiq_invalid // FIQ EL1t
++ kernel_ventry 1, error_invalid // Error EL1t
++
++ kernel_ventry 1, sync // Synchronous EL1h
++ kernel_ventry 1, irq // IRQ EL1h
++ kernel_ventry 1, fiq_invalid // FIQ EL1h
++ kernel_ventry 1, error // Error EL1h
++
++ .rept 4
++ tramp_ventry .Lvector_start\@, 64, 0, \bhb
++ .endr
++ .rept 4
++ tramp_ventry .Lvector_start\@, 32, 0, \bhb
++ .endr
++ .endm
++
++/* The order must match tramp_vecs and the arm64_bp_harden_el1_vectors enum. */
++ .pushsection ".entry.text", "ax"
++ .align 11
++SYM_CODE_START(__bp_harden_el1_vectors)
++#ifdef CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY
++ generate_el1_vector bhb=BHB_MITIGATION_LOOP
++ generate_el1_vector bhb=BHB_MITIGATION_FW
++ generate_el1_vector bhb=BHB_MITIGATION_INSN
++#endif /* CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY */
++SYM_CODE_END(__bp_harden_el1_vectors)
++ .popsection
++
++
+ /*
+ * Register switch for AArch64. The callee-saved registers need to be saved
+ * and restored. On entry:
+@@ -969,13 +1083,7 @@ SYM_CODE_START(__sdei_asm_entry_trampoline)
+ */
+ 1: str x4, [x1, #(SDEI_EVENT_INTREGS + S_ORIG_ADDR_LIMIT)]
+
+-#ifdef CONFIG_RANDOMIZE_BASE
+- adr x4, tramp_vectors + PAGE_SIZE
+- add x4, x4, #:lo12:__sdei_asm_trampoline_next_handler
+- ldr x4, [x4]
+-#else
+- ldr x4, =__sdei_asm_handler
+-#endif
++ tramp_data_read_var x4, __sdei_asm_handler
+ br x4
+ SYM_CODE_END(__sdei_asm_entry_trampoline)
+ NOKPROBE(__sdei_asm_entry_trampoline)
+@@ -998,13 +1106,6 @@ SYM_CODE_END(__sdei_asm_exit_trampoline)
+ NOKPROBE(__sdei_asm_exit_trampoline)
+ .ltorg
+ .popsection // .entry.tramp.text
+-#ifdef CONFIG_RANDOMIZE_BASE
+-.pushsection ".rodata", "a"
+-SYM_DATA_START(__sdei_asm_trampoline_next_handler)
+- .quad __sdei_asm_handler
+-SYM_DATA_END(__sdei_asm_trampoline_next_handler)
+-.popsection // .rodata
+-#endif /* CONFIG_RANDOMIZE_BASE */
+ #endif /* CONFIG_UNMAP_KERNEL_AT_EL0 */
+
+ /*
+@@ -1112,7 +1213,7 @@ alternative_if_not ARM64_UNMAP_KERNEL_AT_EL0
+ alternative_else_nop_endif
+
+ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+- tramp_alias dst=x5, sym=__sdei_asm_exit_trampoline
++ tramp_alias dst=x5, sym=__sdei_asm_exit_trampoline, tmp=x3
+ br x5
+ #endif
+ SYM_CODE_END(__sdei_asm_handler)
+diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c
+index f6e4e3737405d..3dd489b62b29f 100644
+--- a/arch/arm64/kernel/proton-pack.c
++++ b/arch/arm64/kernel/proton-pack.c
+@@ -18,14 +18,18 @@
+ */
+
+ #include <linux/arm-smccc.h>
++#include <linux/bpf.h>
+ #include <linux/cpu.h>
+ #include <linux/device.h>
+ #include <linux/nospec.h>
+ #include <linux/prctl.h>
+ #include <linux/sched/task_stack.h>
+
++#include <asm/insn.h>
+ #include <asm/spectre.h>
+ #include <asm/traps.h>
++#include <asm/vectors.h>
++#include <asm/virt.h>
+
+ /*
+ * We try to ensure that the mitigation state can never change as the result of
+@@ -94,14 +98,51 @@ static bool spectre_v2_mitigations_off(void)
+ return ret;
+ }
+
++static const char *get_bhb_affected_string(enum mitigation_state bhb_state)
++{
++ switch (bhb_state) {
++ case SPECTRE_UNAFFECTED:
++ return "";
++ default:
++ case SPECTRE_VULNERABLE:
++ return ", but not BHB";
++ case SPECTRE_MITIGATED:
++ return ", BHB";
++ }
++}
++
++static bool _unprivileged_ebpf_enabled(void)
++{
++#ifdef CONFIG_BPF_SYSCALL
++ return !sysctl_unprivileged_bpf_disabled;
++#else
++ return false;
++#endif
++}
++
+ ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr,
+ char *buf)
+ {
++ enum mitigation_state bhb_state = arm64_get_spectre_bhb_state();
++ const char *bhb_str = get_bhb_affected_string(bhb_state);
++ const char *v2_str = "Branch predictor hardening";
++
+ switch (spectre_v2_state) {
+ case SPECTRE_UNAFFECTED:
+- return sprintf(buf, "Not affected\n");
++ if (bhb_state == SPECTRE_UNAFFECTED)
++ return sprintf(buf, "Not affected\n");
++
++ /*
++ * Platforms affected by Spectre-BHB can't report
++ * "Not affected" for Spectre-v2.
++ */
++ v2_str = "CSV2";
++ fallthrough;
+ case SPECTRE_MITIGATED:
+- return sprintf(buf, "Mitigation: Branch predictor hardening\n");
++ if (bhb_state == SPECTRE_MITIGATED && _unprivileged_ebpf_enabled())
++ return sprintf(buf, "Vulnerable: Unprivileged eBPF enabled\n");
++
++ return sprintf(buf, "Mitigation: %s%s\n", v2_str, bhb_str);
+ case SPECTRE_VULNERABLE:
+ fallthrough;
+ default:
+@@ -195,9 +236,9 @@ static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
+ __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K);
+ }
+
++static DEFINE_RAW_SPINLOCK(bp_lock);
+ static void install_bp_hardening_cb(bp_hardening_cb_t fn)
+ {
+- static DEFINE_RAW_SPINLOCK(bp_lock);
+ int cpu, slot = -1;
+ const char *hyp_vecs_start = __smccc_workaround_1_smc;
+ const char *hyp_vecs_end = __smccc_workaround_1_smc +
+@@ -228,6 +269,7 @@ static void install_bp_hardening_cb(bp_hardening_cb_t fn)
+
+ __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
+ __this_cpu_write(bp_hardening_data.fn, fn);
++ __this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start);
+ raw_spin_unlock(&bp_lock);
+ }
+ #else
+@@ -571,9 +613,9 @@ void __init spectre_v4_patch_fw_mitigation_enable(struct alt_instr *alt,
+ * Patch a NOP in the Spectre-v4 mitigation code with an SMC/HVC instruction
+ * to call into firmware to adjust the mitigation state.
+ */
+-void __init spectre_v4_patch_fw_mitigation_conduit(struct alt_instr *alt,
+- __le32 *origptr,
+- __le32 *updptr, int nr_inst)
++void __init smccc_patch_fw_mitigation_conduit(struct alt_instr *alt,
++ __le32 *origptr,
++ __le32 *updptr, int nr_inst)
+ {
+ u32 insn;
+
+@@ -787,3 +829,308 @@ int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which)
+ return -ENODEV;
+ }
+ }
++
++/*
++ * Spectre BHB.
++ *
++ * A CPU is either:
++ * - Mitigated by a branchy loop a CPU specific number of times, and listed
++ * in our "loop mitigated list".
++ * - Mitigated in software by the firmware Spectre v2 call.
++ * - Has the ClearBHB instruction to perform the mitigation.
++ * - Has the 'Exception Clears Branch History Buffer' (ECBHB) feature, so no
++ * software mitigation in the vectors is needed.
++ * - Has CSV2.3, so is unaffected.
++ */
++static enum mitigation_state spectre_bhb_state;
++
++enum mitigation_state arm64_get_spectre_bhb_state(void)
++{
++ return spectre_bhb_state;
++}
++
++/*
++ * This must be called with SCOPE_LOCAL_CPU for each type of CPU, before any
++ * SCOPE_SYSTEM call will give the right answer.
++ */
++u8 spectre_bhb_loop_affected(int scope)
++{
++ u8 k = 0;
++ static u8 max_bhb_k;
++
++ if (scope == SCOPE_LOCAL_CPU) {
++ static const struct midr_range spectre_bhb_k32_list[] = {
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A78),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A78C),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_X1),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A710),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_X2),
++ MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N2),
++ MIDR_ALL_VERSIONS(MIDR_NEOVERSE_V1),
++ {},
++ };
++ static const struct midr_range spectre_bhb_k24_list[] = {
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A76),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A77),
++ MIDR_ALL_VERSIONS(MIDR_NEOVERSE_N1),
++ {},
++ };
++ static const struct midr_range spectre_bhb_k8_list[] = {
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A72),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A57),
++ {},
++ };
++
++ if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k32_list))
++ k = 32;
++ else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k24_list))
++ k = 24;
++ else if (is_midr_in_range_list(read_cpuid_id(), spectre_bhb_k8_list))
++ k = 8;
++
++ max_bhb_k = max(max_bhb_k, k);
++ } else {
++ k = max_bhb_k;
++ }
++
++ return k;
++}
++
++static enum mitigation_state spectre_bhb_get_cpu_fw_mitigation_state(void)
++{
++ int ret;
++ struct arm_smccc_res res;
++
++ arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
++ ARM_SMCCC_ARCH_WORKAROUND_3, &res);
++
++ ret = res.a0;
++ switch (ret) {
++ case SMCCC_RET_SUCCESS:
++ return SPECTRE_MITIGATED;
++ case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED:
++ return SPECTRE_UNAFFECTED;
++ default:
++ fallthrough;
++ case SMCCC_RET_NOT_SUPPORTED:
++ return SPECTRE_VULNERABLE;
++ }
++}
++
++static bool is_spectre_bhb_fw_affected(int scope)
++{
++ static bool system_affected;
++ enum mitigation_state fw_state;
++ bool has_smccc = arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_NONE;
++ static const struct midr_range spectre_bhb_firmware_mitigated_list[] = {
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A73),
++ MIDR_ALL_VERSIONS(MIDR_CORTEX_A75),
++ {},
++ };
++ bool cpu_in_list = is_midr_in_range_list(read_cpuid_id(),
++ spectre_bhb_firmware_mitigated_list);
++
++ if (scope != SCOPE_LOCAL_CPU)
++ return system_affected;
++
++ fw_state = spectre_bhb_get_cpu_fw_mitigation_state();
++ if (cpu_in_list || (has_smccc && fw_state == SPECTRE_MITIGATED)) {
++ system_affected = true;
++ return true;
++ }
++
++ return false;
++}
++
++static bool supports_ecbhb(int scope)
++{
++ u64 mmfr1;
++
++ if (scope == SCOPE_LOCAL_CPU)
++ mmfr1 = read_sysreg_s(SYS_ID_AA64MMFR1_EL1);
++ else
++ mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
++
++ return cpuid_feature_extract_unsigned_field(mmfr1,
++ ID_AA64MMFR1_ECBHB_SHIFT);
++}
++
++bool is_spectre_bhb_affected(const struct arm64_cpu_capabilities *entry,
++ int scope)
++{
++ WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible());
++
++ if (supports_csv2p3(scope))
++ return false;
++
++ if (supports_clearbhb(scope))
++ return true;
++
++ if (spectre_bhb_loop_affected(scope))
++ return true;
++
++ if (is_spectre_bhb_fw_affected(scope))
++ return true;
++
++ return false;
++}
++
++static void this_cpu_set_vectors(enum arm64_bp_harden_el1_vectors slot)
++{
++ const char *v = arm64_get_bp_hardening_vector(slot);
++
++ if (slot < 0)
++ return;
++
++ __this_cpu_write(this_cpu_vector, v);
++
++ /*
++ * When KPTI is in use, the vectors are switched when exiting to
++ * user-space.
++ */
++ if (arm64_kernel_unmapped_at_el0())
++ return;
++
++ write_sysreg(v, vbar_el1);
++ isb();
++}
++
++#ifdef CONFIG_KVM
++static int kvm_bhb_get_vecs_size(const char *start)
++{
++ if (start == __smccc_workaround_3_smc)
++ return __SMCCC_WORKAROUND_3_SMC_SZ;
++ else if (start == __spectre_bhb_loop_k8 ||
++ start == __spectre_bhb_loop_k24 ||
++ start == __spectre_bhb_loop_k32)
++ return __SPECTRE_BHB_LOOP_SZ;
++ else if (start == __spectre_bhb_clearbhb)
++ return __SPECTRE_BHB_CLEARBHB_SZ;
++
++ return 0;
++}
++
++static void kvm_setup_bhb_slot(const char *hyp_vecs_start)
++{
++ int cpu, slot = -1, size;
++ const char *hyp_vecs_end;
++
++ if (!IS_ENABLED(CONFIG_KVM) || !is_hyp_mode_available())
++ return;
++
++ size = kvm_bhb_get_vecs_size(hyp_vecs_start);
++ if (WARN_ON_ONCE(!hyp_vecs_start || !size))
++ return;
++ hyp_vecs_end = hyp_vecs_start + size;
++
++ raw_spin_lock(&bp_lock);
++ for_each_possible_cpu(cpu) {
++ if (per_cpu(bp_hardening_data.template_start, cpu) == hyp_vecs_start) {
++ slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu);
++ break;
++ }
++ }
++
++ if (slot == -1) {
++ slot = atomic_inc_return(&arm64_el2_vector_last_slot);
++ BUG_ON(slot >= BP_HARDEN_EL2_SLOTS);
++ __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end);
++ }
++
++ __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot);
++ __this_cpu_write(bp_hardening_data.template_start, hyp_vecs_start);
++ raw_spin_unlock(&bp_lock);
++}
++#else
++#define __smccc_workaround_3_smc NULL
++#define __spectre_bhb_loop_k8 NULL
++#define __spectre_bhb_loop_k24 NULL
++#define __spectre_bhb_loop_k32 NULL
++#define __spectre_bhb_clearbhb NULL
++
++static void kvm_setup_bhb_slot(const char *hyp_vecs_start) { }
++#endif /* CONFIG_KVM */
++
++void spectre_bhb_enable_mitigation(const struct arm64_cpu_capabilities *entry)
++{
++ enum mitigation_state fw_state, state = SPECTRE_VULNERABLE;
++
++ if (!is_spectre_bhb_affected(entry, SCOPE_LOCAL_CPU))
++ return;
++
++ if (arm64_get_spectre_v2_state() == SPECTRE_VULNERABLE) {
++ /* No point mitigating Spectre-BHB alone. */
++ } else if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY)) {
++ pr_info_once("spectre-bhb mitigation disabled by compile time option\n");
++ } else if (cpu_mitigations_off()) {
++ pr_info_once("spectre-bhb mitigation disabled by command line option\n");
++ } else if (supports_ecbhb(SCOPE_LOCAL_CPU)) {
++ state = SPECTRE_MITIGATED;
++ } else if (supports_clearbhb(SCOPE_LOCAL_CPU)) {
++ kvm_setup_bhb_slot(__spectre_bhb_clearbhb);
++ this_cpu_set_vectors(EL1_VECTOR_BHB_CLEAR_INSN);
++
++ state = SPECTRE_MITIGATED;
++ } else if (spectre_bhb_loop_affected(SCOPE_LOCAL_CPU)) {
++ switch (spectre_bhb_loop_affected(SCOPE_SYSTEM)) {
++ case 8:
++ kvm_setup_bhb_slot(__spectre_bhb_loop_k8);
++ break;
++ case 24:
++ kvm_setup_bhb_slot(__spectre_bhb_loop_k24);
++ break;
++ case 32:
++ kvm_setup_bhb_slot(__spectre_bhb_loop_k32);
++ break;
++ default:
++ WARN_ON_ONCE(1);
++ }
++ this_cpu_set_vectors(EL1_VECTOR_BHB_LOOP);
++
++ state = SPECTRE_MITIGATED;
++ } else if (is_spectre_bhb_fw_affected(SCOPE_LOCAL_CPU)) {
++ fw_state = spectre_bhb_get_cpu_fw_mitigation_state();
++ if (fw_state == SPECTRE_MITIGATED) {
++ kvm_setup_bhb_slot(__smccc_workaround_3_smc);
++ this_cpu_set_vectors(EL1_VECTOR_BHB_FW);
++
++ state = SPECTRE_MITIGATED;
++ }
++ }
++
++ update_mitigation_state(&spectre_bhb_state, state);
++}
++
++/* Patched to correct the immediate */
++void noinstr spectre_bhb_patch_loop_iter(struct alt_instr *alt,
++ __le32 *origptr, __le32 *updptr, int nr_inst)
++{
++ u8 rd;
++ u32 insn;
++ u16 loop_count = spectre_bhb_loop_affected(SCOPE_SYSTEM);
++
++ BUG_ON(nr_inst != 1); /* MOV -> MOV */
++
++ if (!IS_ENABLED(CONFIG_MITIGATE_SPECTRE_BRANCH_HISTORY))
++ return;
++
++ insn = le32_to_cpu(*origptr);
++ rd = aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RD, insn);
++ insn = aarch64_insn_gen_movewide(rd, loop_count, 0,
++ AARCH64_INSN_VARIANT_64BIT,
++ AARCH64_INSN_MOVEWIDE_ZERO);
++ *updptr++ = cpu_to_le32(insn);
++}
++
++#ifdef CONFIG_BPF_SYSCALL
++#define EBPF_WARN "Unprivileged eBPF is enabled, data leaks possible via Spectre v2 BHB attacks!\n"
++void unpriv_ebpf_notify(int new_state)
++{
++ if (spectre_v2_state == SPECTRE_VULNERABLE ||
++ spectre_bhb_state != SPECTRE_MITIGATED)
++ return;
++
++ if (!new_state)
++ pr_err("WARNING: %s", EBPF_WARN);
++}
++#endif
+diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
+index 30c1029789427..71f4b5f24d15f 100644
+--- a/arch/arm64/kernel/vmlinux.lds.S
++++ b/arch/arm64/kernel/vmlinux.lds.S
+@@ -299,7 +299,7 @@ ASSERT(__hibernate_exit_text_end - (__hibernate_exit_text_start & ~(SZ_4K - 1))
+ <= SZ_4K, "Hibernate exit text too big or misaligned")
+ #endif
+ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+-ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) == PAGE_SIZE,
++ASSERT((__entry_tramp_text_end - __entry_tramp_text_start) <= 3*PAGE_SIZE,
+ "Entry trampoline text too big")
+ #endif
+ /*
+diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
+index 5bc978be80434..4d63fcd7574b2 100644
+--- a/arch/arm64/kvm/arm.c
++++ b/arch/arm64/kvm/arm.c
+@@ -1337,7 +1337,8 @@ static int kvm_map_vectors(void)
+ * !SV2 + HEL2 -> allocate one vector slot and use exec mapping
+ * SV2 + HEL2 -> use hardened vectors and use exec mapping
+ */
+- if (cpus_have_const_cap(ARM64_SPECTRE_V2)) {
++ if (cpus_have_const_cap(ARM64_SPECTRE_V2) ||
++ cpus_have_const_cap(ARM64_SPECTRE_BHB)) {
+ __kvm_bp_vect_base = kvm_ksym_ref(__bp_harden_hyp_vecs);
+ __kvm_bp_vect_base = kern_hyp_va(__kvm_bp_vect_base);
+ }
+diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S
+index bcbead3746c66..bc06243cf4225 100644
+--- a/arch/arm64/kvm/hyp/hyp-entry.S
++++ b/arch/arm64/kvm/hyp/hyp-entry.S
+@@ -61,6 +61,10 @@ el1_sync: // Guest trapped into EL2
+ /* ARM_SMCCC_ARCH_WORKAROUND_2 handling */
+ eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_1 ^ \
+ ARM_SMCCC_ARCH_WORKAROUND_2)
++ cbz w1, wa_epilogue
++
++ eor w1, w1, #(ARM_SMCCC_ARCH_WORKAROUND_2 ^ \
++ ARM_SMCCC_ARCH_WORKAROUND_3)
+ cbnz w1, el1_trap
+
+ wa_epilogue:
+diff --git a/arch/arm64/kvm/hyp/smccc_wa.S b/arch/arm64/kvm/hyp/smccc_wa.S
+index b0441dbdf68bd..24b281912463d 100644
+--- a/arch/arm64/kvm/hyp/smccc_wa.S
++++ b/arch/arm64/kvm/hyp/smccc_wa.S
+@@ -30,3 +30,78 @@ SYM_DATA_START(__smccc_workaround_1_smc)
+ 1: .org __smccc_workaround_1_smc + __SMCCC_WORKAROUND_1_SMC_SZ
+ .org 1b
+ SYM_DATA_END(__smccc_workaround_1_smc)
++
++ .global __smccc_workaround_3_smc
++SYM_DATA_START(__smccc_workaround_3_smc)
++ esb
++ sub sp, sp, #(8 * 4)
++ stp x2, x3, [sp, #(8 * 0)]
++ stp x0, x1, [sp, #(8 * 2)]
++ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_3
++ smc #0
++ ldp x2, x3, [sp, #(8 * 0)]
++ ldp x0, x1, [sp, #(8 * 2)]
++ add sp, sp, #(8 * 4)
++1: .org __smccc_workaround_3_smc + __SMCCC_WORKAROUND_3_SMC_SZ
++ .org 1b
++SYM_DATA_END(__smccc_workaround_3_smc)
++
++ .global __spectre_bhb_loop_k8
++SYM_DATA_START(__spectre_bhb_loop_k8)
++ esb
++ sub sp, sp, #(8 * 2)
++ stp x0, x1, [sp, #(8 * 0)]
++ mov x0, #8
++2: b . + 4
++ subs x0, x0, #1
++ b.ne 2b
++ dsb nsh
++ isb
++ ldp x0, x1, [sp, #(8 * 0)]
++ add sp, sp, #(8 * 2)
++1: .org __spectre_bhb_loop_k8 + __SPECTRE_BHB_LOOP_SZ
++ .org 1b
++SYM_DATA_END(__spectre_bhb_loop_k8)
++
++ .global __spectre_bhb_loop_k24
++SYM_DATA_START(__spectre_bhb_loop_k24)
++ esb
++ sub sp, sp, #(8 * 2)
++ stp x0, x1, [sp, #(8 * 0)]
++ mov x0, #8
++2: b . + 4
++ subs x0, x0, #1
++ b.ne 2b
++ dsb nsh
++ isb
++ ldp x0, x1, [sp, #(8 * 0)]
++ add sp, sp, #(8 * 2)
++1: .org __spectre_bhb_loop_k24 + __SPECTRE_BHB_LOOP_SZ
++ .org 1b
++SYM_DATA_END(__spectre_bhb_loop_k24)
++
++ .global __spectre_bhb_loop_k32
++SYM_DATA_START(__spectre_bhb_loop_k32)
++ esb
++ sub sp, sp, #(8 * 2)
++ stp x0, x1, [sp, #(8 * 0)]
++ mov x0, #8
++2: b . + 4
++ subs x0, x0, #1
++ b.ne 2b
++ dsb nsh
++ isb
++ ldp x0, x1, [sp, #(8 * 0)]
++ add sp, sp, #(8 * 2)
++1: .org __spectre_bhb_loop_k32 + __SPECTRE_BHB_LOOP_SZ
++ .org 1b
++SYM_DATA_END(__spectre_bhb_loop_k32)
++
++ .global __spectre_bhb_clearbhb
++SYM_DATA_START(__spectre_bhb_clearbhb)
++ esb
++ clearbhb
++ isb
++1: .org __spectre_bhb_clearbhb + __SPECTRE_BHB_CLEARBHB_SZ
++ .org 1b
++SYM_DATA_END(__spectre_bhb_clearbhb)
+diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c
+index 62546e20b2511..532e687f69366 100644
+--- a/arch/arm64/kvm/hyp/vhe/switch.c
++++ b/arch/arm64/kvm/hyp/vhe/switch.c
+@@ -10,6 +10,7 @@
+ #include <linux/kvm_host.h>
+ #include <linux/types.h>
+ #include <linux/jump_label.h>
++#include <linux/percpu.h>
+ #include <uapi/linux/psci.h>
+
+ #include <kvm/arm_psci.h>
+@@ -25,6 +26,7 @@
+ #include <asm/debug-monitors.h>
+ #include <asm/processor.h>
+ #include <asm/thread_info.h>
++#include <asm/vectors.h>
+
+ const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n";
+
+@@ -70,7 +72,7 @@ NOKPROBE_SYMBOL(__activate_traps);
+
+ static void __deactivate_traps(struct kvm_vcpu *vcpu)
+ {
+- extern char vectors[]; /* kernel exception vectors */
++ const char *host_vectors = vectors;
+
+ ___deactivate_traps(vcpu);
+
+@@ -84,7 +86,10 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu)
+ asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
+
+ write_sysreg(CPACR_EL1_DEFAULT, cpacr_el1);
+- write_sysreg(vectors, vbar_el1);
++
++ if (!arm64_kernel_unmapped_at_el0())
++ host_vectors = __this_cpu_read(this_cpu_vector);
++ write_sysreg(host_vectors, vbar_el1);
+ }
+ NOKPROBE_SYMBOL(__deactivate_traps);
+
+diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
+index 25ea4ecb6449f..bc111a1aff032 100644
+--- a/arch/arm64/kvm/hypercalls.c
++++ b/arch/arm64/kvm/hypercalls.c
+@@ -58,6 +58,18 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
+ break;
+ }
+ break;
++ case ARM_SMCCC_ARCH_WORKAROUND_3:
++ switch (arm64_get_spectre_bhb_state()) {
++ case SPECTRE_VULNERABLE:
++ break;
++ case SPECTRE_MITIGATED:
++ val = SMCCC_RET_SUCCESS;
++ break;
++ case SPECTRE_UNAFFECTED:
++ val = SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED;
++ break;
++ }
++ break;
+ case ARM_SMCCC_HV_PV_TIME_FEATURES:
+ val = SMCCC_RET_SUCCESS;
+ break;
+diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c
+index db4056ecccfda..20ba5136ac3dd 100644
+--- a/arch/arm64/kvm/psci.c
++++ b/arch/arm64/kvm/psci.c
+@@ -397,7 +397,7 @@ int kvm_psci_call(struct kvm_vcpu *vcpu)
+
+ int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
+ {
+- return 3; /* PSCI version and two workaround registers */
++ return 4; /* PSCI version and three workaround registers */
+ }
+
+ int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+@@ -411,6 +411,9 @@ int kvm_arm_copy_fw_reg_indices(struct kvm_vcpu *vcpu, u64 __user *uindices)
+ if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2, uindices++))
+ return -EFAULT;
+
++ if (put_user(KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3, uindices++))
++ return -EFAULT;
++
+ return 0;
+ }
+
+@@ -450,6 +453,17 @@ static int get_kernel_wa_level(u64 regid)
+ case SPECTRE_VULNERABLE:
+ return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL;
+ }
++ break;
++ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
++ switch (arm64_get_spectre_bhb_state()) {
++ case SPECTRE_VULNERABLE:
++ return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_AVAIL;
++ case SPECTRE_MITIGATED:
++ return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_AVAIL;
++ case SPECTRE_UNAFFECTED:
++ return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_REQUIRED;
++ }
++ return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3_NOT_AVAIL;
+ }
+
+ return -EINVAL;
+@@ -466,6 +480,7 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+ break;
+ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
+ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2:
++ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
+ val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK;
+ break;
+ default:
+@@ -511,6 +526,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
+ }
+
+ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1:
++ case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3:
+ if (val & ~KVM_REG_FEATURE_LEVEL_MASK)
+ return -EINVAL;
+
+diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
+index 568f11e23830c..835fa036b2d54 100644
+--- a/arch/arm64/kvm/sys_regs.c
++++ b/arch/arm64/kvm/sys_regs.c
+@@ -1517,7 +1517,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
+ /* CRm=6 */
+ ID_SANITISED(ID_AA64ISAR0_EL1),
+ ID_SANITISED(ID_AA64ISAR1_EL1),
+- ID_UNALLOCATED(6,2),
++ ID_SANITISED(ID_AA64ISAR2_EL1),
+ ID_UNALLOCATED(6,3),
+ ID_UNALLOCATED(6,4),
+ ID_UNALLOCATED(6,5),
+diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
+index 2601a514d8c4a..991e599f70577 100644
+--- a/arch/arm64/mm/mmu.c
++++ b/arch/arm64/mm/mmu.c
+@@ -592,6 +592,8 @@ early_param("rodata", parse_rodata);
+ #ifdef CONFIG_UNMAP_KERNEL_AT_EL0
+ static int __init map_entry_trampoline(void)
+ {
++ int i;
++
+ pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;
+ phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start);
+
+@@ -600,11 +602,15 @@ static int __init map_entry_trampoline(void)
+
+ /* Map only the text into the trampoline page table */
+ memset(tramp_pg_dir, 0, PGD_SIZE);
+- __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE,
+- prot, __pgd_pgtable_alloc, 0);
++ __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS,
++ entry_tramp_text_size(), prot,
++ __pgd_pgtable_alloc, NO_BLOCK_MAPPINGS);
+
+ /* Map both the text and data into the kernel page table */
+- __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot);
++ for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++)
++ __set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i,
++ pa_start + i * PAGE_SIZE, prot);
++
+ if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
+ extern char __entry_tramp_data_start[];
+
+diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
+index dad350d42ecfb..3b407f46f1a0d 100644
+--- a/arch/x86/include/asm/cpufeatures.h
++++ b/arch/x86/include/asm/cpufeatures.h
+@@ -204,7 +204,7 @@
+ #define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
+ #define X86_FEATURE_PTI ( 7*32+11) /* Kernel Page Table Isolation enabled */
+ #define X86_FEATURE_RETPOLINE ( 7*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
+-#define X86_FEATURE_RETPOLINE_AMD ( 7*32+13) /* "" AMD Retpoline mitigation for Spectre variant 2 */
++#define X86_FEATURE_RETPOLINE_LFENCE ( 7*32+13) /* "" Use LFENCE for Spectre variant 2 */
+ #define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
+ #define X86_FEATURE_CDP_L2 ( 7*32+15) /* Code and Data Prioritization L2 */
+ #define X86_FEATURE_MSR_SPEC_CTRL ( 7*32+16) /* "" MSR SPEC_CTRL is implemented */
+diff --git a/arch/x86/include/asm/nospec-branch.h b/arch/x86/include/asm/nospec-branch.h
+index cb9ad6b739737..4d0f5386e637b 100644
+--- a/arch/x86/include/asm/nospec-branch.h
++++ b/arch/x86/include/asm/nospec-branch.h
+@@ -82,7 +82,7 @@
+ #ifdef CONFIG_RETPOLINE
+ ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), \
+ __stringify(jmp __x86_retpoline_\reg), X86_FEATURE_RETPOLINE, \
+- __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), X86_FEATURE_RETPOLINE_AMD
++ __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; jmp *%\reg), X86_FEATURE_RETPOLINE_LFENCE
+ #else
+ jmp *%\reg
+ #endif
+@@ -92,7 +92,7 @@
+ #ifdef CONFIG_RETPOLINE
+ ALTERNATIVE_2 __stringify(ANNOTATE_RETPOLINE_SAFE; call *%\reg), \
+ __stringify(call __x86_retpoline_\reg), X86_FEATURE_RETPOLINE, \
+- __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; call *%\reg), X86_FEATURE_RETPOLINE_AMD
++ __stringify(lfence; ANNOTATE_RETPOLINE_SAFE; call *%\reg), X86_FEATURE_RETPOLINE_LFENCE
+ #else
+ call *%\reg
+ #endif
+@@ -134,7 +134,7 @@
+ "lfence;\n" \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%[thunk_target]\n", \
+- X86_FEATURE_RETPOLINE_AMD)
++ X86_FEATURE_RETPOLINE_LFENCE)
+
+ # define THUNK_TARGET(addr) [thunk_target] "r" (addr)
+
+@@ -164,7 +164,7 @@
+ "lfence;\n" \
+ ANNOTATE_RETPOLINE_SAFE \
+ "call *%[thunk_target]\n", \
+- X86_FEATURE_RETPOLINE_AMD)
++ X86_FEATURE_RETPOLINE_LFENCE)
+
+ # define THUNK_TARGET(addr) [thunk_target] "rm" (addr)
+ #endif
+@@ -176,9 +176,11 @@
+ /* The Spectre V2 mitigation variants */
+ enum spectre_v2_mitigation {
+ SPECTRE_V2_NONE,
+- SPECTRE_V2_RETPOLINE_GENERIC,
+- SPECTRE_V2_RETPOLINE_AMD,
+- SPECTRE_V2_IBRS_ENHANCED,
++ SPECTRE_V2_RETPOLINE,
++ SPECTRE_V2_LFENCE,
++ SPECTRE_V2_EIBRS,
++ SPECTRE_V2_EIBRS_RETPOLINE,
++ SPECTRE_V2_EIBRS_LFENCE,
+ };
+
+ /* The indirect branch speculation control variants */
+diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
+index d41b70fe4918e..78b9514a38440 100644
+--- a/arch/x86/kernel/cpu/bugs.c
++++ b/arch/x86/kernel/cpu/bugs.c
+@@ -16,6 +16,7 @@
+ #include <linux/prctl.h>
+ #include <linux/sched/smt.h>
+ #include <linux/pgtable.h>
++#include <linux/bpf.h>
+
+ #include <asm/spec-ctrl.h>
+ #include <asm/cmdline.h>
+@@ -613,6 +614,32 @@ static inline const char *spectre_v2_module_string(void)
+ static inline const char *spectre_v2_module_string(void) { return ""; }
+ #endif
+
++#define SPECTRE_V2_LFENCE_MSG "WARNING: LFENCE mitigation is not recommended for this CPU, data leaks possible!\n"
++#define SPECTRE_V2_EIBRS_EBPF_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS on, data leaks possible via Spectre v2 BHB attacks!\n"
++#define SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG "WARNING: Unprivileged eBPF is enabled with eIBRS+LFENCE mitigation and SMT, data leaks possible via Spectre v2 BHB attacks!\n"
++
++#ifdef CONFIG_BPF_SYSCALL
++void unpriv_ebpf_notify(int new_state)
++{
++ if (new_state)
++ return;
++
++ /* Unprivileged eBPF is enabled */
++
++ switch (spectre_v2_enabled) {
++ case SPECTRE_V2_EIBRS:
++ pr_err(SPECTRE_V2_EIBRS_EBPF_MSG);
++ break;
++ case SPECTRE_V2_EIBRS_LFENCE:
++ if (sched_smt_active())
++ pr_err(SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG);
++ break;
++ default:
++ break;
++ }
++}
++#endif
++
+ static inline bool match_option(const char *arg, int arglen, const char *opt)
+ {
+ int len = strlen(opt);
+@@ -627,7 +654,10 @@ enum spectre_v2_mitigation_cmd {
+ SPECTRE_V2_CMD_FORCE,
+ SPECTRE_V2_CMD_RETPOLINE,
+ SPECTRE_V2_CMD_RETPOLINE_GENERIC,
+- SPECTRE_V2_CMD_RETPOLINE_AMD,
++ SPECTRE_V2_CMD_RETPOLINE_LFENCE,
++ SPECTRE_V2_CMD_EIBRS,
++ SPECTRE_V2_CMD_EIBRS_RETPOLINE,
++ SPECTRE_V2_CMD_EIBRS_LFENCE,
+ };
+
+ enum spectre_v2_user_cmd {
+@@ -700,6 +730,13 @@ spectre_v2_parse_user_cmdline(enum spectre_v2_mitigation_cmd v2_cmd)
+ return SPECTRE_V2_USER_CMD_AUTO;
+ }
+
++static inline bool spectre_v2_in_eibrs_mode(enum spectre_v2_mitigation mode)
++{
++ return (mode == SPECTRE_V2_EIBRS ||
++ mode == SPECTRE_V2_EIBRS_RETPOLINE ||
++ mode == SPECTRE_V2_EIBRS_LFENCE);
++}
++
+ static void __init
+ spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
+ {
+@@ -767,7 +804,7 @@ spectre_v2_user_select_mitigation(enum spectre_v2_mitigation_cmd v2_cmd)
+ */
+ if (!boot_cpu_has(X86_FEATURE_STIBP) ||
+ !smt_possible ||
+- spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
++ spectre_v2_in_eibrs_mode(spectre_v2_enabled))
+ return;
+
+ /*
+@@ -787,9 +824,11 @@ set_mode:
+
+ static const char * const spectre_v2_strings[] = {
+ [SPECTRE_V2_NONE] = "Vulnerable",
+- [SPECTRE_V2_RETPOLINE_GENERIC] = "Mitigation: Full generic retpoline",
+- [SPECTRE_V2_RETPOLINE_AMD] = "Mitigation: Full AMD retpoline",
+- [SPECTRE_V2_IBRS_ENHANCED] = "Mitigation: Enhanced IBRS",
++ [SPECTRE_V2_RETPOLINE] = "Mitigation: Retpolines",
++ [SPECTRE_V2_LFENCE] = "Mitigation: LFENCE",
++ [SPECTRE_V2_EIBRS] = "Mitigation: Enhanced IBRS",
++ [SPECTRE_V2_EIBRS_LFENCE] = "Mitigation: Enhanced IBRS + LFENCE",
++ [SPECTRE_V2_EIBRS_RETPOLINE] = "Mitigation: Enhanced IBRS + Retpolines",
+ };
+
+ static const struct {
+@@ -800,8 +839,12 @@ static const struct {
+ { "off", SPECTRE_V2_CMD_NONE, false },
+ { "on", SPECTRE_V2_CMD_FORCE, true },
+ { "retpoline", SPECTRE_V2_CMD_RETPOLINE, false },
+- { "retpoline,amd", SPECTRE_V2_CMD_RETPOLINE_AMD, false },
++ { "retpoline,amd", SPECTRE_V2_CMD_RETPOLINE_LFENCE, false },
++ { "retpoline,lfence", SPECTRE_V2_CMD_RETPOLINE_LFENCE, false },
+ { "retpoline,generic", SPECTRE_V2_CMD_RETPOLINE_GENERIC, false },
++ { "eibrs", SPECTRE_V2_CMD_EIBRS, false },
++ { "eibrs,lfence", SPECTRE_V2_CMD_EIBRS_LFENCE, false },
++ { "eibrs,retpoline", SPECTRE_V2_CMD_EIBRS_RETPOLINE, false },
+ { "auto", SPECTRE_V2_CMD_AUTO, false },
+ };
+
+@@ -838,17 +881,30 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
+ }
+
+ if ((cmd == SPECTRE_V2_CMD_RETPOLINE ||
+- cmd == SPECTRE_V2_CMD_RETPOLINE_AMD ||
+- cmd == SPECTRE_V2_CMD_RETPOLINE_GENERIC) &&
++ cmd == SPECTRE_V2_CMD_RETPOLINE_LFENCE ||
++ cmd == SPECTRE_V2_CMD_RETPOLINE_GENERIC ||
++ cmd == SPECTRE_V2_CMD_EIBRS_LFENCE ||
++ cmd == SPECTRE_V2_CMD_EIBRS_RETPOLINE) &&
+ !IS_ENABLED(CONFIG_RETPOLINE)) {
+- pr_err("%s selected but not compiled in. Switching to AUTO select\n", mitigation_options[i].option);
++ pr_err("%s selected but not compiled in. Switching to AUTO select\n",
++ mitigation_options[i].option);
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
+- if (cmd == SPECTRE_V2_CMD_RETPOLINE_AMD &&
+- boot_cpu_data.x86_vendor != X86_VENDOR_HYGON &&
+- boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
+- pr_err("retpoline,amd selected but CPU is not AMD. Switching to AUTO select\n");
++ if ((cmd == SPECTRE_V2_CMD_EIBRS ||
++ cmd == SPECTRE_V2_CMD_EIBRS_LFENCE ||
++ cmd == SPECTRE_V2_CMD_EIBRS_RETPOLINE) &&
++ !boot_cpu_has(X86_FEATURE_IBRS_ENHANCED)) {
++ pr_err("%s selected but CPU doesn't have eIBRS. Switching to AUTO select\n",
++ mitigation_options[i].option);
++ return SPECTRE_V2_CMD_AUTO;
++ }
++
++ if ((cmd == SPECTRE_V2_CMD_RETPOLINE_LFENCE ||
++ cmd == SPECTRE_V2_CMD_EIBRS_LFENCE) &&
++ !boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) {
++ pr_err("%s selected, but CPU doesn't have a serializing LFENCE. Switching to AUTO select\n",
++ mitigation_options[i].option);
+ return SPECTRE_V2_CMD_AUTO;
+ }
+
+@@ -857,6 +913,16 @@ static enum spectre_v2_mitigation_cmd __init spectre_v2_parse_cmdline(void)
+ return cmd;
+ }
+
++static enum spectre_v2_mitigation __init spectre_v2_select_retpoline(void)
++{
++ if (!IS_ENABLED(CONFIG_RETPOLINE)) {
++ pr_err("Kernel not compiled with retpoline; no mitigation available!");
++ return SPECTRE_V2_NONE;
++ }
++
++ return SPECTRE_V2_RETPOLINE;
++}
++
+ static void __init spectre_v2_select_mitigation(void)
+ {
+ enum spectre_v2_mitigation_cmd cmd = spectre_v2_parse_cmdline();
+@@ -877,49 +943,64 @@ static void __init spectre_v2_select_mitigation(void)
+ case SPECTRE_V2_CMD_FORCE:
+ case SPECTRE_V2_CMD_AUTO:
+ if (boot_cpu_has(X86_FEATURE_IBRS_ENHANCED)) {
+- mode = SPECTRE_V2_IBRS_ENHANCED;
+- /* Force it so VMEXIT will restore correctly */
+- x86_spec_ctrl_base |= SPEC_CTRL_IBRS;
+- wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
+- goto specv2_set_mode;
++ mode = SPECTRE_V2_EIBRS;
++ break;
+ }
+- if (IS_ENABLED(CONFIG_RETPOLINE))
+- goto retpoline_auto;
++
++ mode = spectre_v2_select_retpoline();
+ break;
+- case SPECTRE_V2_CMD_RETPOLINE_AMD:
+- if (IS_ENABLED(CONFIG_RETPOLINE))
+- goto retpoline_amd;
++
++ case SPECTRE_V2_CMD_RETPOLINE_LFENCE:
++ pr_err(SPECTRE_V2_LFENCE_MSG);
++ mode = SPECTRE_V2_LFENCE;
+ break;
++
+ case SPECTRE_V2_CMD_RETPOLINE_GENERIC:
+- if (IS_ENABLED(CONFIG_RETPOLINE))
+- goto retpoline_generic;
++ mode = SPECTRE_V2_RETPOLINE;
+ break;
++
+ case SPECTRE_V2_CMD_RETPOLINE:
+- if (IS_ENABLED(CONFIG_RETPOLINE))
+- goto retpoline_auto;
++ mode = spectre_v2_select_retpoline();
++ break;
++
++ case SPECTRE_V2_CMD_EIBRS:
++ mode = SPECTRE_V2_EIBRS;
++ break;
++
++ case SPECTRE_V2_CMD_EIBRS_LFENCE:
++ mode = SPECTRE_V2_EIBRS_LFENCE;
++ break;
++
++ case SPECTRE_V2_CMD_EIBRS_RETPOLINE:
++ mode = SPECTRE_V2_EIBRS_RETPOLINE;
+ break;
+ }
+- pr_err("Spectre mitigation: kernel not compiled with retpoline; no mitigation available!");
+- return;
+
+-retpoline_auto:
+- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
+- boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
+- retpoline_amd:
+- if (!boot_cpu_has(X86_FEATURE_LFENCE_RDTSC)) {
+- pr_err("Spectre mitigation: LFENCE not serializing, switching to generic retpoline\n");
+- goto retpoline_generic;
+- }
+- mode = SPECTRE_V2_RETPOLINE_AMD;
+- setup_force_cpu_cap(X86_FEATURE_RETPOLINE_AMD);
+- setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
+- } else {
+- retpoline_generic:
+- mode = SPECTRE_V2_RETPOLINE_GENERIC;
++ if (mode == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
++ pr_err(SPECTRE_V2_EIBRS_EBPF_MSG);
++
++ if (spectre_v2_in_eibrs_mode(mode)) {
++ /* Force it so VMEXIT will restore correctly */
++ x86_spec_ctrl_base |= SPEC_CTRL_IBRS;
++ wrmsrl(MSR_IA32_SPEC_CTRL, x86_spec_ctrl_base);
++ }
++
++ switch (mode) {
++ case SPECTRE_V2_NONE:
++ case SPECTRE_V2_EIBRS:
++ break;
++
++ case SPECTRE_V2_LFENCE:
++ case SPECTRE_V2_EIBRS_LFENCE:
++ setup_force_cpu_cap(X86_FEATURE_RETPOLINE_LFENCE);
++ fallthrough;
++
++ case SPECTRE_V2_RETPOLINE:
++ case SPECTRE_V2_EIBRS_RETPOLINE:
+ setup_force_cpu_cap(X86_FEATURE_RETPOLINE);
++ break;
+ }
+
+-specv2_set_mode:
+ spectre_v2_enabled = mode;
+ pr_info("%s\n", spectre_v2_strings[mode]);
+
+@@ -945,7 +1026,7 @@ specv2_set_mode:
+ * the CPU supports Enhanced IBRS, kernel might un-intentionally not
+ * enable IBRS around firmware calls.
+ */
+- if (boot_cpu_has(X86_FEATURE_IBRS) && mode != SPECTRE_V2_IBRS_ENHANCED) {
++ if (boot_cpu_has(X86_FEATURE_IBRS) && !spectre_v2_in_eibrs_mode(mode)) {
+ setup_force_cpu_cap(X86_FEATURE_USE_IBRS_FW);
+ pr_info("Enabling Restricted Speculation for firmware calls\n");
+ }
+@@ -1015,6 +1096,10 @@ void cpu_bugs_smt_update(void)
+ {
+ mutex_lock(&spec_ctrl_mutex);
+
++ if (sched_smt_active() && unprivileged_ebpf_enabled() &&
++ spectre_v2_enabled == SPECTRE_V2_EIBRS_LFENCE)
++ pr_warn_once(SPECTRE_V2_EIBRS_LFENCE_EBPF_SMT_MSG);
++
+ switch (spectre_v2_user_stibp) {
+ case SPECTRE_V2_USER_NONE:
+ break;
+@@ -1621,7 +1706,7 @@ static ssize_t tsx_async_abort_show_state(char *buf)
+
+ static char *stibp_state(void)
+ {
+- if (spectre_v2_enabled == SPECTRE_V2_IBRS_ENHANCED)
++ if (spectre_v2_in_eibrs_mode(spectre_v2_enabled))
+ return "";
+
+ switch (spectre_v2_user_stibp) {
+@@ -1651,6 +1736,27 @@ static char *ibpb_state(void)
+ return "";
+ }
+
++static ssize_t spectre_v2_show_state(char *buf)
++{
++ if (spectre_v2_enabled == SPECTRE_V2_LFENCE)
++ return sprintf(buf, "Vulnerable: LFENCE\n");
++
++ if (spectre_v2_enabled == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
++ return sprintf(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");
++
++ if (sched_smt_active() && unprivileged_ebpf_enabled() &&
++ spectre_v2_enabled == SPECTRE_V2_EIBRS_LFENCE)
++ return sprintf(buf, "Vulnerable: eIBRS+LFENCE with unprivileged eBPF and SMT\n");
++
++ return sprintf(buf, "%s%s%s%s%s%s\n",
++ spectre_v2_strings[spectre_v2_enabled],
++ ibpb_state(),
++ boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "",
++ stibp_state(),
++ boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "",
++ spectre_v2_module_string());
++}
++
+ static ssize_t srbds_show_state(char *buf)
+ {
+ return sprintf(buf, "%s\n", srbds_strings[srbds_mitigation]);
+@@ -1676,12 +1782,7 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
+ return sprintf(buf, "%s\n", spectre_v1_strings[spectre_v1_mitigation]);
+
+ case X86_BUG_SPECTRE_V2:
+- return sprintf(buf, "%s%s%s%s%s%s\n", spectre_v2_strings[spectre_v2_enabled],
+- ibpb_state(),
+- boot_cpu_has(X86_FEATURE_USE_IBRS_FW) ? ", IBRS_FW" : "",
+- stibp_state(),
+- boot_cpu_has(X86_FEATURE_RSB_CTXSW) ? ", RSB filling" : "",
+- spectre_v2_module_string());
++ return spectre_v2_show_state(buf);
+
+ case X86_BUG_SPEC_STORE_BYPASS:
+ return sprintf(buf, "%s\n", ssb_strings[ssb_mode]);
+diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
+index 8347eaee679c8..3f2e5ea9ab6b7 100644
+--- a/drivers/acpi/ec.c
++++ b/drivers/acpi/ec.c
+@@ -2064,16 +2064,6 @@ bool acpi_ec_dispatch_gpe(void)
+ if (acpi_any_gpe_status_set(first_ec->gpe))
+ return true;
+
+- /*
+- * Cancel the SCI wakeup and process all pending events in case there
+- * are any wakeup ones in there.
+- *
+- * Note that if any non-EC GPEs are active at this point, the SCI will
+- * retrigger after the rearming in acpi_s2idle_wake(), so no events
+- * should be missed by canceling the wakeup here.
+- */
+- pm_system_cancel_wakeup();
+-
+ /*
+ * Dispatch the EC GPE in-band, but do not report wakeup in any case
+ * to allow the caller to process events properly after that.
+diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
+index e2614ea820bb8..503935b1deeb1 100644
+--- a/drivers/acpi/sleep.c
++++ b/drivers/acpi/sleep.c
+@@ -1012,15 +1012,21 @@ static bool acpi_s2idle_wake(void)
+ return true;
+ }
+
+- /*
+- * Check non-EC GPE wakeups and if there are none, cancel the
+- * SCI-related wakeup and dispatch the EC GPE.
+- */
++ /* Check non-EC GPE wakeups and dispatch the EC GPE. */
+ if (acpi_ec_dispatch_gpe()) {
+ pm_pr_dbg("ACPI non-EC GPE wakeup\n");
+ return true;
+ }
+
++ /*
++ * Cancel the SCI wakeup and process all pending events in case
++ * there are any wakeup ones in there.
++ *
++ * Note that if any non-EC GPEs are active at this point, the
++ * SCI will retrigger after the rearming below, so no events
++ * should be missed by canceling the wakeup here.
++ */
++ pm_system_cancel_wakeup();
+ acpi_os_wait_events_complete();
+
+ /*
+diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
+index 22842d2938c28..47d4bb23d6f31 100644
+--- a/drivers/block/xen-blkfront.c
++++ b/drivers/block/xen-blkfront.c
+@@ -1352,7 +1352,8 @@ free_shadow:
+ rinfo->ring_ref[i] = GRANT_INVALID_REF;
+ }
+ }
+- free_pages((unsigned long)rinfo->ring.sring, get_order(info->nr_ring_pages * XEN_PAGE_SIZE));
++ free_pages_exact(rinfo->ring.sring,
++ info->nr_ring_pages * XEN_PAGE_SIZE);
+ rinfo->ring.sring = NULL;
+
+ if (rinfo->irq)
+@@ -1436,9 +1437,15 @@ static int blkif_get_final_status(enum blk_req_status s1,
+ return BLKIF_RSP_OKAY;
+ }
+
+-static bool blkif_completion(unsigned long *id,
+- struct blkfront_ring_info *rinfo,
+- struct blkif_response *bret)
++/*
++ * Return values:
++ * 1 response processed.
++ * 0 missing further responses.
++ * -1 error while processing.
++ */
++static int blkif_completion(unsigned long *id,
++ struct blkfront_ring_info *rinfo,
++ struct blkif_response *bret)
+ {
+ int i = 0;
+ struct scatterlist *sg;
+@@ -1461,7 +1468,7 @@ static bool blkif_completion(unsigned long *id,
+
+ /* Wait the second response if not yet here. */
+ if (s2->status < REQ_DONE)
+- return false;
++ return 0;
+
+ bret->status = blkif_get_final_status(s->status,
+ s2->status);
+@@ -1512,42 +1519,43 @@ static bool blkif_completion(unsigned long *id,
+ }
+ /* Add the persistent grant into the list of free grants */
+ for (i = 0; i < num_grant; i++) {
+- if (gnttab_query_foreign_access(s->grants_used[i]->gref)) {
++ if (!gnttab_try_end_foreign_access(s->grants_used[i]->gref)) {
+ /*
+ * If the grant is still mapped by the backend (the
+ * backend has chosen to make this grant persistent)
+ * we add it at the head of the list, so it will be
+ * reused first.
+ */
+- if (!info->feature_persistent)
+- pr_alert_ratelimited("backed has not unmapped grant: %u\n",
+- s->grants_used[i]->gref);
++ if (!info->feature_persistent) {
++ pr_alert("backed has not unmapped grant: %u\n",
++ s->grants_used[i]->gref);
++ return -1;
++ }
+ list_add(&s->grants_used[i]->node, &rinfo->grants);
+ rinfo->persistent_gnts_c++;
+ } else {
+ /*
+- * If the grant is not mapped by the backend we end the
+- * foreign access and add it to the tail of the list,
+- * so it will not be picked again unless we run out of
+- * persistent grants.
++ * If the grant is not mapped by the backend we add it
++ * to the tail of the list, so it will not be picked
++ * again unless we run out of persistent grants.
+ */
+- gnttab_end_foreign_access(s->grants_used[i]->gref, 0, 0UL);
+ s->grants_used[i]->gref = GRANT_INVALID_REF;
+ list_add_tail(&s->grants_used[i]->node, &rinfo->grants);
+ }
+ }
+ if (s->req.operation == BLKIF_OP_INDIRECT) {
+ for (i = 0; i < INDIRECT_GREFS(num_grant); i++) {
+- if (gnttab_query_foreign_access(s->indirect_grants[i]->gref)) {
+- if (!info->feature_persistent)
+- pr_alert_ratelimited("backed has not unmapped grant: %u\n",
+- s->indirect_grants[i]->gref);
++ if (!gnttab_try_end_foreign_access(s->indirect_grants[i]->gref)) {
++ if (!info->feature_persistent) {
++ pr_alert("backed has not unmapped grant: %u\n",
++ s->indirect_grants[i]->gref);
++ return -1;
++ }
+ list_add(&s->indirect_grants[i]->node, &rinfo->grants);
+ rinfo->persistent_gnts_c++;
+ } else {
+ struct page *indirect_page;
+
+- gnttab_end_foreign_access(s->indirect_grants[i]->gref, 0, 0UL);
+ /*
+ * Add the used indirect page back to the list of
+ * available pages for indirect grefs.
+@@ -1562,7 +1570,7 @@ static bool blkif_completion(unsigned long *id,
+ }
+ }
+
+- return true;
++ return 1;
+ }
+
+ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
+@@ -1628,12 +1636,17 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
+ }
+
+ if (bret.operation != BLKIF_OP_DISCARD) {
++ int ret;
++
+ /*
+ * We may need to wait for an extra response if the
+ * I/O request is split in 2
+ */
+- if (!blkif_completion(&id, rinfo, &bret))
++ ret = blkif_completion(&id, rinfo, &bret);
++ if (!ret)
+ continue;
++ if (unlikely(ret < 0))
++ goto err;
+ }
+
+ if (add_id_to_freelist(rinfo, id)) {
+@@ -1740,8 +1753,7 @@ static int setup_blkring(struct xenbus_device *dev,
+ for (i = 0; i < info->nr_ring_pages; i++)
+ rinfo->ring_ref[i] = GRANT_INVALID_REF;
+
+- sring = (struct blkif_sring *)__get_free_pages(GFP_NOIO | __GFP_HIGH,
+- get_order(ring_size));
++ sring = alloc_pages_exact(ring_size, GFP_NOIO);
+ if (!sring) {
+ xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
+ return -ENOMEM;
+@@ -1751,7 +1763,7 @@ static int setup_blkring(struct xenbus_device *dev,
+
+ err = xenbus_grant_ring(dev, rinfo->ring.sring, info->nr_ring_pages, gref);
+ if (err < 0) {
+- free_pages((unsigned long)sring, get_order(ring_size));
++ free_pages_exact(sring, ring_size);
+ rinfo->ring.sring = NULL;
+ goto fail;
+ }
+@@ -2729,11 +2741,10 @@ static void purge_persistent_grants(struct blkfront_info *info)
+ list_for_each_entry_safe(gnt_list_entry, tmp, &rinfo->grants,
+ node) {
+ if (gnt_list_entry->gref == GRANT_INVALID_REF ||
+- gnttab_query_foreign_access(gnt_list_entry->gref))
++ !gnttab_try_end_foreign_access(gnt_list_entry->gref))
+ continue;
+
+ list_del(&gnt_list_entry->node);
+- gnttab_end_foreign_access(gnt_list_entry->gref, 0, 0UL);
+ rinfo->persistent_gnts_c--;
+ gnt_list_entry->gref = GRANT_INVALID_REF;
+ list_add_tail(&gnt_list_entry->node, &rinfo->grants);
+diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
+index 7ed8872d08c60..1a69b5246133b 100644
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -424,14 +424,12 @@ static bool xennet_tx_buf_gc(struct netfront_queue *queue)
+ queue->tx_link[id] = TX_LINK_NONE;
+ skb = queue->tx_skbs[id];
+ queue->tx_skbs[id] = NULL;
+- if (unlikely(gnttab_query_foreign_access(
+- queue->grant_tx_ref[id]) != 0)) {
++ if (unlikely(!gnttab_end_foreign_access_ref(
++ queue->grant_tx_ref[id], GNTMAP_readonly))) {
+ dev_alert(dev,
+ "Grant still in use by backend domain\n");
+ goto err;
+ }
+- gnttab_end_foreign_access_ref(
+- queue->grant_tx_ref[id], GNTMAP_readonly);
+ gnttab_release_grant_reference(
+ &queue->gref_tx_head, queue->grant_tx_ref[id]);
+ queue->grant_tx_ref[id] = GRANT_INVALID_REF;
+@@ -992,7 +990,6 @@ static int xennet_get_responses(struct netfront_queue *queue,
+ struct device *dev = &queue->info->netdev->dev;
+ struct bpf_prog *xdp_prog;
+ struct xdp_buff xdp;
+- unsigned long ret;
+ int slots = 1;
+ int err = 0;
+ u32 verdict;
+@@ -1034,8 +1031,13 @@ static int xennet_get_responses(struct netfront_queue *queue,
+ goto next;
+ }
+
+- ret = gnttab_end_foreign_access_ref(ref, 0);
+- BUG_ON(!ret);
++ if (!gnttab_end_foreign_access_ref(ref, 0)) {
++ dev_alert(dev,
++ "Grant still in use by backend domain\n");
++ queue->info->broken = true;
++ dev_alert(dev, "Disabled for further use\n");
++ return -EINVAL;
++ }
+
+ gnttab_release_grant_reference(&queue->gref_rx_head, ref);
+
+@@ -1256,6 +1258,10 @@ static int xennet_poll(struct napi_struct *napi, int budget)
+ &need_xdp_flush);
+
+ if (unlikely(err)) {
++ if (queue->info->broken) {
++ spin_unlock(&queue->rx_lock);
++ return 0;
++ }
+ err:
+ while ((skb = __skb_dequeue(&tmpq)))
+ __skb_queue_tail(&errq, skb);
+@@ -1920,7 +1926,7 @@ static int setup_netfront(struct xenbus_device *dev,
+ struct netfront_queue *queue, unsigned int feature_split_evtchn)
+ {
+ struct xen_netif_tx_sring *txs;
+- struct xen_netif_rx_sring *rxs;
++ struct xen_netif_rx_sring *rxs = NULL;
+ grant_ref_t gref;
+ int err;
+
+@@ -1940,21 +1946,21 @@ static int setup_netfront(struct xenbus_device *dev,
+
+ err = xenbus_grant_ring(dev, txs, 1, &gref);
+ if (err < 0)
+- goto grant_tx_ring_fail;
++ goto fail;
+ queue->tx_ring_ref = gref;
+
+ rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
+ if (!rxs) {
+ err = -ENOMEM;
+ xenbus_dev_fatal(dev, err, "allocating rx ring page");
+- goto alloc_rx_ring_fail;
++ goto fail;
+ }
+ SHARED_RING_INIT(rxs);
+ FRONT_RING_INIT(&queue->rx, rxs, XEN_PAGE_SIZE);
+
+ err = xenbus_grant_ring(dev, rxs, 1, &gref);
+ if (err < 0)
+- goto grant_rx_ring_fail;
++ goto fail;
+ queue->rx_ring_ref = gref;
+
+ if (feature_split_evtchn)
+@@ -1967,22 +1973,28 @@ static int setup_netfront(struct xenbus_device *dev,
+ err = setup_netfront_single(queue);
+
+ if (err)
+- goto alloc_evtchn_fail;
++ goto fail;
+
+ return 0;
+
+ /* If we fail to setup netfront, it is safe to just revoke access to
+ * granted pages because backend is not accessing it at this point.
+ */
+-alloc_evtchn_fail:
+- gnttab_end_foreign_access_ref(queue->rx_ring_ref, 0);
+-grant_rx_ring_fail:
+- free_page((unsigned long)rxs);
+-alloc_rx_ring_fail:
+- gnttab_end_foreign_access_ref(queue->tx_ring_ref, 0);
+-grant_tx_ring_fail:
+- free_page((unsigned long)txs);
+-fail:
++ fail:
++ if (queue->rx_ring_ref != GRANT_INVALID_REF) {
++ gnttab_end_foreign_access(queue->rx_ring_ref, 0,
++ (unsigned long)rxs);
++ queue->rx_ring_ref = GRANT_INVALID_REF;
++ } else {
++ free_page((unsigned long)rxs);
++ }
++ if (queue->tx_ring_ref != GRANT_INVALID_REF) {
++ gnttab_end_foreign_access(queue->tx_ring_ref, 0,
++ (unsigned long)txs);
++ queue->tx_ring_ref = GRANT_INVALID_REF;
++ } else {
++ free_page((unsigned long)txs);
++ }
+ return err;
+ }
+
+diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
+index 259fc248d06cf..a25c9386fdf78 100644
+--- a/drivers/scsi/xen-scsifront.c
++++ b/drivers/scsi/xen-scsifront.c
+@@ -233,12 +233,11 @@ static void scsifront_gnttab_done(struct vscsifrnt_info *info,
+ return;
+
+ for (i = 0; i < shadow->nr_grants; i++) {
+- if (unlikely(gnttab_query_foreign_access(shadow->gref[i]))) {
++ if (unlikely(!gnttab_try_end_foreign_access(shadow->gref[i]))) {
+ shost_printk(KERN_ALERT, info->host, KBUILD_MODNAME
+ "grant still in use by backend\n");
+ BUG();
+ }
+- gnttab_end_foreign_access(shadow->gref[i], 0, 0UL);
+ }
+
+ kfree(shadow->sg);
+diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
+index 3fa40c723e8e9..edb0acd0b8323 100644
+--- a/drivers/xen/gntalloc.c
++++ b/drivers/xen/gntalloc.c
+@@ -169,20 +169,14 @@ undo:
+ __del_gref(gref);
+ }
+
+- /* It's possible for the target domain to map the just-allocated grant
+- * references by blindly guessing their IDs; if this is done, then
+- * __del_gref will leave them in the queue_gref list. They need to be
+- * added to the global list so that we can free them when they are no
+- * longer referenced.
+- */
+- if (unlikely(!list_empty(&queue_gref)))
+- list_splice_tail(&queue_gref, &gref_list);
+ mutex_unlock(&gref_mutex);
+ return rc;
+ }
+
+ static void __del_gref(struct gntalloc_gref *gref)
+ {
++ unsigned long addr;
++
+ if (gref->notify.flags & UNMAP_NOTIFY_CLEAR_BYTE) {
+ uint8_t *tmp = kmap(gref->page);
+ tmp[gref->notify.pgoff] = 0;
+@@ -196,21 +190,16 @@ static void __del_gref(struct gntalloc_gref *gref)
+ gref->notify.flags = 0;
+
+ if (gref->gref_id) {
+- if (gnttab_query_foreign_access(gref->gref_id))
+- return;
+-
+- if (!gnttab_end_foreign_access_ref(gref->gref_id, 0))
+- return;
+-
+- gnttab_free_grant_reference(gref->gref_id);
++ if (gref->page) {
++ addr = (unsigned long)page_to_virt(gref->page);
++ gnttab_end_foreign_access(gref->gref_id, 0, addr);
++ } else
++ gnttab_free_grant_reference(gref->gref_id);
+ }
+
+ gref_size--;
+ list_del(&gref->next_gref);
+
+- if (gref->page)
+- __free_page(gref->page);
+-
+ kfree(gref);
+ }
+
+diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c
+index 3729bea0c9895..5c83d41766c85 100644
+--- a/drivers/xen/grant-table.c
++++ b/drivers/xen/grant-table.c
+@@ -134,12 +134,9 @@ struct gnttab_ops {
+ */
+ unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref);
+ /*
+- * Query the status of a grant entry. Ref parameter is reference of
+- * queried grant entry, return value is the status of queried entry.
+- * Detailed status(writing/reading) can be gotten from the return value
+- * by bit operations.
++ * Read the frame number related to a given grant reference.
+ */
+- int (*query_foreign_access)(grant_ref_t ref);
++ unsigned long (*read_frame)(grant_ref_t ref);
+ };
+
+ struct unmap_refs_callback_data {
+@@ -284,22 +281,6 @@ int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
+ }
+ EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);
+
+-static int gnttab_query_foreign_access_v1(grant_ref_t ref)
+-{
+- return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing);
+-}
+-
+-static int gnttab_query_foreign_access_v2(grant_ref_t ref)
+-{
+- return grstatus[ref] & (GTF_reading|GTF_writing);
+-}
+-
+-int gnttab_query_foreign_access(grant_ref_t ref)
+-{
+- return gnttab_interface->query_foreign_access(ref);
+-}
+-EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
+-
+ static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
+ {
+ u16 flags, nflags;
+@@ -353,6 +334,16 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
+ }
+ EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
+
++static unsigned long gnttab_read_frame_v1(grant_ref_t ref)
++{
++ return gnttab_shared.v1[ref].frame;
++}
++
++static unsigned long gnttab_read_frame_v2(grant_ref_t ref)
++{
++ return gnttab_shared.v2[ref].full_page.frame;
++}
++
+ struct deferred_entry {
+ struct list_head list;
+ grant_ref_t ref;
+@@ -382,12 +373,9 @@ static void gnttab_handle_deferred(struct timer_list *unused)
+ spin_unlock_irqrestore(&gnttab_list_lock, flags);
+ if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) {
+ put_free_entry(entry->ref);
+- if (entry->page) {
+- pr_debug("freeing g.e. %#x (pfn %#lx)\n",
+- entry->ref, page_to_pfn(entry->page));
+- put_page(entry->page);
+- } else
+- pr_info("freeing g.e. %#x\n", entry->ref);
++ pr_debug("freeing g.e. %#x (pfn %#lx)\n",
++ entry->ref, page_to_pfn(entry->page));
++ put_page(entry->page);
+ kfree(entry);
+ entry = NULL;
+ } else {
+@@ -412,9 +400,18 @@ static void gnttab_handle_deferred(struct timer_list *unused)
+ static void gnttab_add_deferred(grant_ref_t ref, bool readonly,
+ struct page *page)
+ {
+- struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
++ struct deferred_entry *entry;
++ gfp_t gfp = (in_atomic() || irqs_disabled()) ? GFP_ATOMIC : GFP_KERNEL;
+ const char *what = KERN_WARNING "leaking";
+
++ entry = kmalloc(sizeof(*entry), gfp);
++ if (!page) {
++ unsigned long gfn = gnttab_interface->read_frame(ref);
++
++ page = pfn_to_page(gfn_to_pfn(gfn));
++ get_page(page);
++ }
++
+ if (entry) {
+ unsigned long flags;
+
+@@ -435,11 +432,21 @@ static void gnttab_add_deferred(grant_ref_t ref, bool readonly,
+ what, ref, page ? page_to_pfn(page) : -1);
+ }
+
++int gnttab_try_end_foreign_access(grant_ref_t ref)
++{
++ int ret = _gnttab_end_foreign_access_ref(ref, 0);
++
++ if (ret)
++ put_free_entry(ref);
++
++ return ret;
++}
++EXPORT_SYMBOL_GPL(gnttab_try_end_foreign_access);
++
+ void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
+ unsigned long page)
+ {
+- if (gnttab_end_foreign_access_ref(ref, readonly)) {
+- put_free_entry(ref);
++ if (gnttab_try_end_foreign_access(ref)) {
+ if (page != 0)
+ put_page(virt_to_page(page));
+ } else
+@@ -1417,7 +1424,7 @@ static const struct gnttab_ops gnttab_v1_ops = {
+ .update_entry = gnttab_update_entry_v1,
+ .end_foreign_access_ref = gnttab_end_foreign_access_ref_v1,
+ .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1,
+- .query_foreign_access = gnttab_query_foreign_access_v1,
++ .read_frame = gnttab_read_frame_v1,
+ };
+
+ static const struct gnttab_ops gnttab_v2_ops = {
+@@ -1429,7 +1436,7 @@ static const struct gnttab_ops gnttab_v2_ops = {
+ .update_entry = gnttab_update_entry_v2,
+ .end_foreign_access_ref = gnttab_end_foreign_access_ref_v2,
+ .end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v2,
+- .query_foreign_access = gnttab_query_foreign_access_v2,
++ .read_frame = gnttab_read_frame_v2,
+ };
+
+ static bool gnttab_need_v2(void)
+diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
+index 7984645b59563..bbe337dc296e3 100644
+--- a/drivers/xen/pvcalls-front.c
++++ b/drivers/xen/pvcalls-front.c
+@@ -337,8 +337,8 @@ static void free_active_ring(struct sock_mapping *map)
+ if (!map->active.ring)
+ return;
+
+- free_pages((unsigned long)map->active.data.in,
+- map->active.ring->ring_order);
++ free_pages_exact(map->active.data.in,
++ PAGE_SIZE << map->active.ring->ring_order);
+ free_page((unsigned long)map->active.ring);
+ }
+
+@@ -352,8 +352,8 @@ static int alloc_active_ring(struct sock_mapping *map)
+ goto out;
+
+ map->active.ring->ring_order = PVCALLS_RING_ORDER;
+- bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+- PVCALLS_RING_ORDER);
++ bytes = alloc_pages_exact(PAGE_SIZE << PVCALLS_RING_ORDER,
++ GFP_KERNEL | __GFP_ZERO);
+ if (!bytes)
+ goto out;
+
+diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
+index 0cd728961fce9..16cfef0993295 100644
+--- a/drivers/xen/xenbus/xenbus_client.c
++++ b/drivers/xen/xenbus/xenbus_client.c
+@@ -379,7 +379,14 @@ int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
+ unsigned int nr_pages, grant_ref_t *grefs)
+ {
+ int err;
+- int i, j;
++ unsigned int i;
++ grant_ref_t gref_head;
++
++ err = gnttab_alloc_grant_references(nr_pages, &gref_head);
++ if (err) {
++ xenbus_dev_fatal(dev, err, "granting access to ring page");
++ return err;
++ }
+
+ for (i = 0; i < nr_pages; i++) {
+ unsigned long gfn;
+@@ -389,23 +396,14 @@ int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr,
+ else
+ gfn = virt_to_gfn(vaddr);
+
+- err = gnttab_grant_foreign_access(dev->otherend_id, gfn, 0);
+- if (err < 0) {
+- xenbus_dev_fatal(dev, err,
+- "granting access to ring page");
+- goto fail;
+- }
+- grefs[i] = err;
++ grefs[i] = gnttab_claim_grant_reference(&gref_head);
++ gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,
++ gfn, 0);
+
+ vaddr = vaddr + XEN_PAGE_SIZE;
+ }
+
+ return 0;
+-
+-fail:
+- for (j = 0; j < i; j++)
+- gnttab_end_foreign_access_ref(grefs[j], 0);
+- return err;
+ }
+ EXPORT_SYMBOL_GPL(xenbus_grant_ring);
+
+diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
+index f860645f65128..ff38737475ecb 100644
+--- a/include/linux/arm-smccc.h
++++ b/include/linux/arm-smccc.h
+@@ -87,6 +87,11 @@
+ ARM_SMCCC_SMC_32, \
+ 0, 0x7fff)
+
++#define ARM_SMCCC_ARCH_WORKAROUND_3 \
++ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
++ ARM_SMCCC_SMC_32, \
++ 0, 0x3fff)
++
+ #define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1
+
+ /* Paravirtualised time calls (defined by ARM DEN0057A) */
+diff --git a/include/linux/bpf.h b/include/linux/bpf.h
+index e6ddf5a3beaf8..ea3ff499e94a3 100644
+--- a/include/linux/bpf.h
++++ b/include/linux/bpf.h
+@@ -1485,6 +1485,12 @@ struct bpf_prog *bpf_prog_by_id(u32 id);
+ struct bpf_link *bpf_link_by_id(u32 id);
+
+ const struct bpf_func_proto *bpf_base_func_proto(enum bpf_func_id func_id);
++
++static inline bool unprivileged_ebpf_enabled(void)
++{
++ return !sysctl_unprivileged_bpf_disabled;
++}
++
+ #else /* !CONFIG_BPF_SYSCALL */
+ static inline struct bpf_prog *bpf_prog_get(u32 ufd)
+ {
+@@ -1679,6 +1685,12 @@ bpf_base_func_proto(enum bpf_func_id func_id)
+ {
+ return NULL;
+ }
++
++static inline bool unprivileged_ebpf_enabled(void)
++{
++ return false;
++}
++
+ #endif /* CONFIG_BPF_SYSCALL */
+
+ static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
+diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h
+index 0b1182a3cf412..57b4ae6a4a186 100644
+--- a/include/xen/grant_table.h
++++ b/include/xen/grant_table.h
+@@ -97,17 +97,32 @@ int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
+ * access has been ended, free the given page too. Access will be ended
+ * immediately iff the grant entry is not in use, otherwise it will happen
+ * some time later. page may be 0, in which case no freeing will occur.
++ * Note that the granted page might still be accessed (read or write) by the
++ * other side after gnttab_end_foreign_access() returns, so even if page was
++ * specified as 0 it is not allowed to just reuse the page for other
++ * purposes immediately. gnttab_end_foreign_access() will take an additional
++ * reference to the granted page in this case, which is dropped only after
++ * the grant is no longer in use.
++ * This requires that multi page allocations for areas subject to
++ * gnttab_end_foreign_access() are done via alloc_pages_exact() (and freeing
++ * via free_pages_exact()) in order to avoid high order pages.
+ */
+ void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
+ unsigned long page);
+
++/*
++ * End access through the given grant reference, iff the grant entry is
++ * no longer in use. In case of success ending foreign access, the
++ * grant reference is deallocated.
++ * Return 1 if the grant entry was freed, 0 if it is still in use.
++ */
++int gnttab_try_end_foreign_access(grant_ref_t ref);
++
+ int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
+
+ unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
+ unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
+
+-int gnttab_query_foreign_access(grant_ref_t ref);
+-
+ /*
+ * operations on reserved batches of grant references
+ */
+diff --git a/kernel/sysctl.c b/kernel/sysctl.c
+index 72ceb19574d0c..8832440a4938e 100644
+--- a/kernel/sysctl.c
++++ b/kernel/sysctl.c
+@@ -234,6 +234,10 @@ static int bpf_stats_handler(struct ctl_table *table, int write,
+ return ret;
+ }
+
++void __weak unpriv_ebpf_notify(int new_state)
++{
++}
++
+ static int bpf_unpriv_handler(struct ctl_table *table, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+ {
+@@ -251,6 +255,9 @@ static int bpf_unpriv_handler(struct ctl_table *table, int write,
+ return -EPERM;
+ *(int *)table->data = unpriv_enable;
+ }
++
++ unpriv_ebpf_notify(unpriv_enable);
++
+ return ret;
+ }
+ #endif /* CONFIG_BPF_SYSCALL && CONFIG_SYSCTL */
+diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
+index 3ec1a51a6944e..432ac5a16f2e0 100644
+--- a/net/9p/trans_xen.c
++++ b/net/9p/trans_xen.c
+@@ -304,9 +304,9 @@ static void xen_9pfs_front_free(struct xen_9pfs_front_priv *priv)
+ ref = priv->rings[i].intf->ref[j];
+ gnttab_end_foreign_access(ref, 0, 0);
+ }
+- free_pages((unsigned long)priv->rings[i].data.in,
+- priv->rings[i].intf->ring_order -
+- (PAGE_SHIFT - XEN_PAGE_SHIFT));
++ free_pages_exact(priv->rings[i].data.in,
++ 1UL << (priv->rings[i].intf->ring_order +
++ XEN_PAGE_SHIFT));
+ }
+ gnttab_end_foreign_access(priv->rings[i].ref, 0, 0);
+ free_page((unsigned long)priv->rings[i].intf);
+@@ -345,8 +345,8 @@ static int xen_9pfs_front_alloc_dataring(struct xenbus_device *dev,
+ if (ret < 0)
+ goto out;
+ ring->ref = ret;
+- bytes = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+- order - (PAGE_SHIFT - XEN_PAGE_SHIFT));
++ bytes = alloc_pages_exact(1UL << (order + XEN_PAGE_SHIFT),
++ GFP_KERNEL | __GFP_ZERO);
+ if (!bytes) {
+ ret = -ENOMEM;
+ goto out;
+@@ -377,9 +377,7 @@ out:
+ if (bytes) {
+ for (i--; i >= 0; i--)
+ gnttab_end_foreign_access(ring->intf->ref[i], 0, 0);
+- free_pages((unsigned long)bytes,
+- ring->intf->ring_order -
+- (PAGE_SHIFT - XEN_PAGE_SHIFT));
++ free_pages_exact(bytes, 1UL << (order + XEN_PAGE_SHIFT));
+ }
+ gnttab_end_foreign_access(ring->ref, 0, 0);
+ free_page((unsigned long)ring->intf);
+diff --git a/tools/arch/x86/include/asm/cpufeatures.h b/tools/arch/x86/include/asm/cpufeatures.h
+index dad350d42ecfb..b58730cc12e83 100644
+--- a/tools/arch/x86/include/asm/cpufeatures.h
++++ b/tools/arch/x86/include/asm/cpufeatures.h
+@@ -204,7 +204,7 @@
+ #define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
+ #define X86_FEATURE_PTI ( 7*32+11) /* Kernel Page Table Isolation enabled */
+ #define X86_FEATURE_RETPOLINE ( 7*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
+-#define X86_FEATURE_RETPOLINE_AMD ( 7*32+13) /* "" AMD Retpoline mitigation for Spectre variant 2 */
++#define X86_FEATURE_RETPOLINE_LFENCE ( 7*32+13) /* "" Use LFENCEs for Spectre variant 2 */
+ #define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
+ #define X86_FEATURE_CDP_L2 ( 7*32+15) /* Code and Data Prioritization L2 */
+ #define X86_FEATURE_MSR_SPEC_CTRL ( 7*32+16) /* "" MSR SPEC_CTRL is implemented */