Re: [PATCH 26/33] x86/kvm: Add stack frame dependency to test_cc() inline asm

From: Josh Poimboeuf
Date: Fri Jan 22 2016 - 11:02:55 EST


On Fri, Jan 22, 2016 at 11:05:06AM +0100, Paolo Bonzini wrote:
>
>
> On 21/01/2016 23:49, Josh Poimboeuf wrote:
> > With some configs, gcc doesn't inline test_cc(). When that happens, it
> > doesn't create a stack frame before inserting the call instruction.
> > This breaks frame pointer convention if CONFIG_FRAME_POINTER is enabled
> > and can result in a bad stack trace.
> >
> > Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
> > listing the stack pointer as an output operand for the inline asm
> > statement.
>
> If an __always_inline allocation works, that would be better.

Yeah, that seems to work. I'll update the patch.

--
Josh