On Mon, Nov 26, 2012 at 02:48:50PM -0800, H. Peter Anvin wrote: > On 11/25/2012 11:22 PM, Paolo Bonzini wrote: > > Il 21/11/2012 23:41, H. Peter Anvin ha scritto: > >> From: "H. Peter Anvin" <hpa@xxxxxxxxxxxxxxx> > >> > >> In __emulate_1op_rax_rdx, we use "+a" and "+d" which are input/output > >> constraints, and *then* use "a" and "d" as input constraints. This is > >> incorrect, but happens to work on some versions of gcc. > >> > >> However, it breaks gcc with -O0 and icc, and may break on future > >> versions of gcc. > >> > >> Reported-and-tested-by: Melanie Blower <melanie.blower@xxxxxxxxx> > >> Signed-off-by: H. Peter Anvin <hpa@xxxxxxxxxxxxxxx> > >> Link: http://lkml.kernel.org/r/B3584E72CFEBED439A3ECA9BCE67A4EF1B17AF90@xxxxxxxxxxxxxxxxxxxxxxxxxxxx > >> --- > >> arch/x86/kvm/emulate.c | 3 +-- > >> 1 file changed, 1 insertion(+), 2 deletions(-) > >> > >> diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > >> index 39171cb..bba39bf 100644 > >> --- a/arch/x86/kvm/emulate.c > >> +++ b/arch/x86/kvm/emulate.c > >> @@ -426,8 +426,7 @@ static void invalidate_registers(struct x86_emulate_ctxt *ctxt) > >> _ASM_EXTABLE(1b, 3b) \ > >> : "=m" ((ctxt)->eflags), "=&r" (_tmp), \ > >> "+a" (*rax), "+d" (*rdx), "+qm"(_ex) \ > >> - : "i" (EFLAGS_MASK), "m" ((ctxt)->src.val), \ > >> - "a" (*rax), "d" (*rdx)); \ > >> + : "i" (EFLAGS_MASK), "m" ((ctxt)->src.val)); \ > >> } while (0) > >> > >> /* instruction has only one source operand, destination is implicit (e.g. mul, div, imul, idiv) */ > >> > > > > Reviewed-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> > > > > Gleb, Marcelo: are you going to apply this or would you prefer I took it > in x86/urgent? > > -hpa Feel free to merge it through x86/urgent. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
