This is a note to let you know that I've just added the patch titled
x86: Prepare inline-asm for straight-line-speculation
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-prepare-inline-asm-for-straight-line-speculation.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Jul 12 05:07:35 PM CEST 2022
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Date: Sat, 4 Dec 2021 14:43:41 +0100
Subject: x86: Prepare inline-asm for straight-line-speculation
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
commit b17c2baa305cccbd16bafa289fd743cc2db77966 upstream.
Replace all ret/retq instructions with ASM_RET in preparation of
making it more than a single instruction.
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20211204134907.964635458@xxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 5.10: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/linkage.h | 4 ++++
arch/x86/include/asm/paravirt.h | 2 +-
arch/x86/include/asm/qspinlock_paravirt.h | 4 ++--
arch/x86/kernel/alternative.c | 2 +-
arch/x86/kernel/kprobes/core.c | 2 +-
arch/x86/kernel/paravirt.c | 2 +-
arch/x86/kvm/emulate.c | 4 ++--
arch/x86/lib/error-inject.c | 3 ++-
samples/ftrace/ftrace-direct-modify.c | 4 ++--
samples/ftrace/ftrace-direct-too.c | 2 +-
samples/ftrace/ftrace-direct.c | 2 +-
11 files changed, 18 insertions(+), 13 deletions(-)
--- a/arch/x86/include/asm/linkage.h
+++ b/arch/x86/include/asm/linkage.h
@@ -18,6 +18,10 @@
#define __ALIGN_STR __stringify(__ALIGN)
#endif
+#else /* __ASSEMBLY__ */
+
+#define ASM_RET "ret\n\t"
+
#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_LINKAGE_H */
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -630,7 +630,7 @@ bool __raw_callee_save___native_vcpu_is_
"call " #func ";" \
PV_RESTORE_ALL_CALLER_REGS \
FRAME_END \
- "ret;" \
+ ASM_RET \
".size " PV_THUNK_NAME(func) ", .-" PV_THUNK_NAME(func) ";" \
".popsection")
--- a/arch/x86/include/asm/qspinlock_paravirt.h
+++ b/arch/x86/include/asm/qspinlock_paravirt.h
@@ -48,7 +48,7 @@ asm (".pushsection .text;"
"jne .slowpath;"
"pop %rdx;"
FRAME_END
- "ret;"
+ ASM_RET
".slowpath: "
"push %rsi;"
"movzbl %al,%esi;"
@@ -56,7 +56,7 @@ asm (".pushsection .text;"
"pop %rsi;"
"pop %rdx;"
FRAME_END
- "ret;"
+ ASM_RET
".size " PV_UNLOCK ", .-" PV_UNLOCK ";"
".popsection");
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -869,7 +869,7 @@ asm (
" .type int3_magic, @function\n"
"int3_magic:\n"
" movl $1, (%" _ASM_ARG1 ")\n"
-" ret\n"
+ ASM_RET
" .size int3_magic, .-int3_magic\n"
" .popsection\n"
);
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -768,7 +768,7 @@ asm(
RESTORE_REGS_STRING
" popfl\n"
#endif
- " ret\n"
+ ASM_RET
".size kretprobe_trampoline, .-kretprobe_trampoline\n"
);
NOKPROBE_SYMBOL(kretprobe_trampoline);
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -40,7 +40,7 @@ extern void _paravirt_nop(void);
asm (".pushsection .entry.text, \"ax\"\n"
".global _paravirt_nop\n"
"_paravirt_nop:\n\t"
- "ret\n\t"
+ ASM_RET
".size _paravirt_nop, . - _paravirt_nop\n\t"
".type _paravirt_nop, @function\n\t"
".popsection");
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -316,7 +316,7 @@ static int fastop(struct x86_emulate_ctx
__FOP_FUNC(#name)
#define __FOP_RET(name) \
- "ret \n\t" \
+ ASM_RET \
".size " name ", .-" name "\n\t"
#define FOP_RET(name) \
@@ -437,7 +437,7 @@ static int fastop(struct x86_emulate_ctx
asm(".pushsection .fixup, \"ax\"\n"
".global kvm_fastop_exception \n"
- "kvm_fastop_exception: xor %esi, %esi; ret\n"
+ "kvm_fastop_exception: xor %esi, %esi; " ASM_RET
".popsection");
FOP_START(setcc)
--- a/arch/x86/lib/error-inject.c
+++ b/arch/x86/lib/error-inject.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: GPL-2.0
+#include <linux/linkage.h>
#include <linux/error-injection.h>
#include <linux/kprobes.h>
@@ -10,7 +11,7 @@ asm(
".type just_return_func, @function\n"
".globl just_return_func\n"
"just_return_func:\n"
- " ret\n"
+ ASM_RET
".size just_return_func, .-just_return_func\n"
);
--- a/samples/ftrace/ftrace-direct-modify.c
+++ b/samples/ftrace/ftrace-direct-modify.c
@@ -31,7 +31,7 @@ asm (
" call my_direct_func1\n"
" leave\n"
" .size my_tramp1, .-my_tramp1\n"
-" ret\n"
+ ASM_RET
" .type my_tramp2, @function\n"
" .globl my_tramp2\n"
" my_tramp2:"
@@ -39,7 +39,7 @@ asm (
" movq %rsp, %rbp\n"
" call my_direct_func2\n"
" leave\n"
-" ret\n"
+ ASM_RET
" .size my_tramp2, .-my_tramp2\n"
" .popsection\n"
);
--- a/samples/ftrace/ftrace-direct-too.c
+++ b/samples/ftrace/ftrace-direct-too.c
@@ -31,7 +31,7 @@ asm (
" popq %rsi\n"
" popq %rdi\n"
" leave\n"
-" ret\n"
+ ASM_RET
" .size my_tramp, .-my_tramp\n"
" .popsection\n"
);
--- a/samples/ftrace/ftrace-direct.c
+++ b/samples/ftrace/ftrace-direct.c
@@ -24,7 +24,7 @@ asm (
" call my_direct_func\n"
" popq %rdi\n"
" leave\n"
-" ret\n"
+ ASM_RET
" .size my_tramp, .-my_tramp\n"
" .popsection\n"
);
Patches currently in stable-queue which might be from peterz@xxxxxxxxxxxxx are
queue-5.10/objtool-cache-instruction-relocs.patch
queue-5.10/x86-sev-avoid-using-__x86_return_thunk.patch
queue-5.10/objtool-add-elf_create_undef_symbol.patch
queue-5.10/x86-ftrace-use-alternative-ret-encoding.patch
queue-5.10/objtool-re-add-unwind_hint_-save_restore.patch
queue-5.10/x86-bugs-add-retbleed-ibpb.patch
queue-5.10/x86-bugs-enable-stibp-for-jmp2ret.patch
queue-5.10/x86-retpoline-cleanup-some-ifdefery.patch
queue-5.10/objtool-handle-__sanitize_cov-tail-calls.patch
queue-5.10/x86-prepare-asm-files-for-straight-line-speculation.patch
queue-5.10/kvm-vmx-flatten-__vmx_vcpu_run.patch
queue-5.10/x86-kvm-vmx-make-noinstr-clean.patch
queue-5.10/objtool-x86-replace-alternatives-with-.retpoline_sites.patch
queue-5.10/objtool-skip-magical-retpoline-.altinstr_replacement.patch
queue-5.10/x86-retbleed-add-fine-grained-kconfig-knobs.patch
queue-5.10/x86-cpu-amd-add-spectral-chicken.patch
queue-5.10/objtool-add-straight-line-speculation-validation.patch
queue-5.10/kvm-vmx-fix-ibrs-handling-after-vmexit.patch
queue-5.10/kvm-vmx-prevent-guest-rsb-poisoning-attacks-with-eibrs.patch
queue-5.10/x86-vsyscall_emu-64-don-t-use-ret-in-vsyscall-emulation.patch
queue-5.10/tools-arch-update-arch-x86-lib-mem-cpy-set-_64.s-copies-used-in-perf-bench-mem-memcpy.patch
queue-5.10/x86-add-straight-line-speculation-mitigation.patch
queue-5.10/x86-add-magic-amd-return-thunk.patch
queue-5.10/x86-bugs-keep-a-per-cpu-ia32_spec_ctrl-value.patch
queue-5.10/x86-alternatives-optimize-optimize_nops.patch
queue-5.10/x86-objtool-create-.return_sites.patch
queue-5.10/crypto-x86-poly1305-fixup-sls.patch
queue-5.10/x86-alternative-handle-jcc-__x86_indirect_thunk_-reg.patch
queue-5.10/x86-kvm-fix-setcc-emulation-for-return-thunks.patch
queue-5.10/objtool-fix-objtool-regression-on-x32-systems.patch
queue-5.10/x86-alternative-relax-text_poke_bp-constraint.patch
queue-5.10/x86-retpoline-swizzle-retpoline-thunk.patch
queue-5.10/objtool-rework-the-elf_rebuild_reloc_section-logic.patch
queue-5.10/x86-speculation-fix-firmware-entry-spec_ctrl-handling.patch
queue-5.10/x86-retpoline-remove-unused-replacement-symbols.patch
queue-5.10/objtool-fix-symbol-creation.patch
queue-5.10/x86-speculation-add-spectre_v2-ibrs-option-to-support-kernel-ibrs.patch
queue-5.10/bpf-x86-respect-x86_feature_retpoline.patch
queue-5.10/objtool-fix-type-of-reloc-addend.patch
queue-5.10/objtool-x86-rewrite-retpoline-thunk-calls.patch
queue-5.10/x86-undo-return-thunk-damage.patch
queue-5.10/x86-prepare-inline-asm-for-straight-line-speculation.patch
queue-5.10/x86-alternative-support-alternative_ternary.patch
queue-5.10/kvm-emulate-fix-setcc-emulation-function-offsets-with-sls.patch
queue-5.10/objtool-handle-per-arch-retpoline-naming.patch
queue-5.10/x86-retpoline-create-a-retpoline-thunk-array.patch
queue-5.10/x86-retpoline-simplify-retpolines.patch
queue-5.10/x86-asm-fix-register-order.patch
queue-5.10/x86-speculation-fill-rsb-on-vmexit-for-ibrs.patch
queue-5.10/objtool-add-entry-unret-validation.patch
queue-5.10/objtool-keep-track-of-retpoline-call-sites.patch
queue-5.10/kvm-vmx-convert-launched-argument-to-flags.patch
queue-5.10/objtool-add-elf_create_reloc-helper.patch
queue-5.10/objtool-make-.altinstructions-section-entry-size-consistent.patch
queue-5.10/x86-bpf-use-alternative-ret-encoding.patch
queue-5.10/x86-common-stamp-out-the-stepping-madness.patch
queue-5.10/x86-bugs-split-spectre_v2_select_mitigation-and-spectre_v2_user_select_mitigation.patch
queue-5.10/x86-bugs-report-intel-retbleed-vulnerability.patch
queue-5.10/bpf-x86-simplify-computing-label-offsets.patch
queue-5.10/x86-cpufeatures-move-retpoline-flags-to-word-11.patch
queue-5.10/x86-speculation-fix-spec_ctrl-write-on-smt-state-change.patch
queue-5.10/x86-retpoline-use-mfunction-return.patch
queue-5.10/x86-xen-rename-sys-entry-points.patch
queue-5.10/objtool-only-rewrite-unconditional-retpoline-thunk-calls.patch
queue-5.10/x86-bugs-optimize-spec_ctrl-msr-writes.patch
queue-5.10/x86-alternative-optimize-single-byte-nops-at-an-arbitrary-position.patch
queue-5.10/objtool-fix-code-relocs-vs-weak-symbols.patch
queue-5.10/x86-bugs-report-amd-retbleed-vulnerability.patch
queue-5.10/x86-static_call-use-alternative-ret-encoding.patch
queue-5.10/x86-speculation-fix-rsb-filling-with-config_retpoline-n.patch
queue-5.10/x86-asm-fixup-odd-gen-for-each-reg.h-usage.patch
queue-5.10/x86-alternative-add-debug-prints-to-apply_retpolines.patch
queue-5.10/objtool-extract-elf_symbol_add.patch
queue-5.10/x86-use-return-thunk-in-asm-code.patch
queue-5.10/objtool-remove-reloc-symbol-type-checks-in-get_alt_entry.patch
queue-5.10/objtool-classify-symbols.patch
queue-5.10/intel_idle-disable-ibrs-during-long-idle.patch
queue-5.10/objtool-correctly-handle-retpoline-thunk-calls.patch
queue-5.10/objtool-fix-.symtab_shndx-handling-for-elf_create_undef_symbol.patch
queue-5.10/x86-retpoline-move-the-retpoline-thunk-declarations-to-nospec-branch.h.patch
queue-5.10/objtool-support-asm-jump-tables.patch
queue-5.10/x86-alternative-implement-.retpoline_sites-support.patch
queue-5.10/objtool-x86-ignore-__x86_indirect_alt_-symbols.patch
queue-5.10/objtool-fix-sls-validation-for-kcov-tail-call-replacement.patch
queue-5.10/x86-alternative-try-inline-spectre_v2-retpoline-amd.patch
queue-5.10/x86-entry-remove-skip_r11rcx.patch
queue-5.10/objtool-explicitly-avoid-self-modifying-code-in-.altinstr_replacement.patch
queue-5.10/x86-speculation-use-cached-host-spec_ctrl-value-for-guest-entry-exit.patch
queue-5.10/x86-bugs-add-amd-retbleed-boot-parameter.patch
queue-5.10/objtool-create-reloc-sections-implicitly.patch
queue-5.10/x86-entry-add-kernel-ibrs-implementation.patch
queue-5.10/objtool-treat-.text.__x86.-as-noinstr.patch
queue-5.10/x86-lib-atomic64_386_32-rename-things.patch
queue-5.10/objtool-introduce-cfi-hash.patch
queue-5.10/objtool-default-ignore-int3-for-unreachable.patch
queue-5.10/objtool-extract-elf_strtab_concat.patch
queue-5.10/objtool-teach-get_alt_entry-about-more-relocation-types.patch
queue-5.10/objtool-update-retpoline-validation.patch
