Il 21/11/2012 23:41, H. Peter Anvin ha scritto: > From: "H. Peter Anvin" <h...@linux.intel.com> > > 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.blo...@intel.com> > Signed-off-by: H. Peter Anvin <h...@linux.intel.com> > Link: > http://lkml.kernel.org/r/b3584e72cfebed439a3eca9bce67a4ef1b17a...@fmsmsx107.amr.corp.intel.com > --- > 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 <pbonz...@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
