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| author | Peter Zijlstra <peterz@infradead.org> | 2021-11-10 13:01:16 +0300 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2021-12-11 11:09:48 +0300 |
| commit | c9a34c3f4ece192f6d804039fe6aac9618f0d236 (patch) | |
| tree | 414ce438b3cc0312010e52031f117707b60426b5 | |
| parent | 5fc77b916cb82fe476ae2344e0ec37445227a4f8 (diff) | |
| download | linux-c9a34c3f4ece192f6d804039fe6aac9618f0d236.tar.xz | |
x86/kvm: Remove .fixup usage
KVM instruction emulation has a gnarly hack where the .fixup does a
return, however there's already a ret right after the 10b label, so
mark that as 11 and have the exception clear %esi to remove the
.fixup.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20211110101325.722157053@infradead.org
| -rw-r--r-- | arch/x86/include/asm/extable_fixup_types.h | 1 | ||||
| -rw-r--r-- | arch/x86/kvm/emulate.c | 16 |
2 files changed, 5 insertions, 12 deletions
diff --git a/arch/x86/include/asm/extable_fixup_types.h b/arch/x86/include/asm/extable_fixup_types.h index a43b8c128e74..31ad42f1a76e 100644 --- a/arch/x86/include/asm/extable_fixup_types.h +++ b/arch/x86/include/asm/extable_fixup_types.h @@ -46,5 +46,6 @@ #define EX_TYPE_IMM_REG 17 /* reg := (long)imm */ #define EX_TYPE_EFAULT_REG (EX_TYPE_IMM_REG | EX_DATA_IMM(-EFAULT)) #define EX_TYPE_ZERO_REG (EX_TYPE_IMM_REG | EX_DATA_IMM(0)) +#define EX_TYPE_ONE_REG (EX_TYPE_IMM_REG | EX_DATA_IMM(1)) #endif diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index b026350c04c7..1e19a4de441f 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -315,7 +315,7 @@ static int fastop(struct x86_emulate_ctxt *ctxt, fastop_t fop); __FOP_FUNC(#name) #define __FOP_RET(name) \ - ASM_RET \ + "11: " ASM_RET \ ".size " name ", .-" name "\n\t" #define FOP_RET(name) \ @@ -344,7 +344,7 @@ static int fastop(struct x86_emulate_ctxt *ctxt, fastop_t fop); __FOP_RET(#op "_" #dst) #define FOP1EEX(op, dst) \ - FOP1E(op, dst) _ASM_EXTABLE(10b, kvm_fastop_exception) + FOP1E(op, dst) _ASM_EXTABLE_TYPE_REG(10b, 11b, EX_TYPE_ZERO_REG, %%esi) #define FASTOP1(op) \ FOP_START(op) \ @@ -434,10 +434,6 @@ static int fastop(struct x86_emulate_ctxt *ctxt, fastop_t fop); #op " %al \n\t" \ __FOP_RET(#op) -asm(".pushsection .fixup, \"ax\"\n" - "kvm_fastop_exception: xor %esi, %esi; " ASM_RET - ".popsection"); - FOP_START(setcc) FOP_SETCC(seto) FOP_SETCC(setno) @@ -473,12 +469,8 @@ FOP_END; \ asm volatile("1:" insn "\n" \ "2:\n" \ - ".pushsection .fixup, \"ax\"\n" \ - "3: movl $1, %[_fault]\n" \ - " jmp 2b\n" \ - ".popsection\n" \ - _ASM_EXTABLE(1b, 3b) \ - : [_fault] "+qm"(_fault) inoutclob ); \ + _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_ONE_REG, %[_fault]) \ + : [_fault] "+r"(_fault) inoutclob ); \ \ _fault ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE; \ }) |