diff options
| author | Radim Krčmář <rkrcmar@redhat.com> | 2016-11-08 20:54:18 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-01-19 20:17:19 +0100 |
| commit | d9c4c1e7c2cf4feed8b86e508fb76ac14607f131 (patch) | |
| tree | c24b40d7a52fde2d3ab854568af19e885d5e5787 /arch/x86 | |
| parent | 4fa0090249fb3b5d12b8207900cbea8ff23cfd8b (diff) | |
KVM: x86: add asm_safe wrapper
commit aabba3c6abd50b05b1fc2c6ec44244aa6bcda576 upstream.
Move the existing exception handling for inline assembly into a macro
and switch its return values to X86EMUL type.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 34 |
1 files changed, 23 insertions, 11 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 058dd7847f35..5035b74169dc 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -435,6 +435,26 @@ FOP_END; FOP_START(salc) "pushf; sbb %al, %al; popf \n\t" FOP_RET FOP_END; +/* + * XXX: inoutclob user must know where the argument is being expanded. + * Relying on CC_HAVE_ASM_GOTO would allow us to remove _fault. + */ +#define asm_safe(insn, inoutclob...) \ +({ \ + int _fault = 0; \ + \ + 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 ); \ + \ + _fault ? X86EMUL_UNHANDLEABLE : X86EMUL_CONTINUE; \ +}) + static int emulator_check_intercept(struct x86_emulate_ctxt *ctxt, enum x86_intercept intercept, enum x86_intercept_stage stage) @@ -5086,21 +5106,13 @@ static bool string_insn_completed(struct x86_emulate_ctxt *ctxt) static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt) { - bool fault = false; + int rc; ctxt->ops->get_fpu(ctxt); - asm volatile("1: fwait \n\t" - "2: \n\t" - ".pushsection .fixup,\"ax\" \n\t" - "3: \n\t" - "movb $1, %[fault] \n\t" - "jmp 2b \n\t" - ".popsection \n\t" - _ASM_EXTABLE(1b, 3b) - : [fault]"+qm"(fault)); + rc = asm_safe("fwait"); ctxt->ops->put_fpu(ctxt); - if (unlikely(fault)) + if (unlikely(rc != X86EMUL_CONTINUE)) return emulate_exception(ctxt, MF_VECTOR, 0, false); return X86EMUL_CONTINUE; |