Re: [PATCH] [20/45] x86_64: Use 8 byte stack alignment when possible

Andi Kleen
2007-09-30T22:08:18Z

On Friday 21 September 2007 23:19:35 Jakub Jelinek wrote:
> On Fri, Sep 21, 2007 at 10:45:02PM +0200, Andi Kleen wrote:
> >
> > Kernel doesn't use SSE2, so it doesn't need 16 byte alignment. Also
> > the stack can be already unaligned so letting the compiler align
> > is useless. This may make some stack frames smaller.
>
> Shouldn't sources that are compiled into the VDSO or VSYSCALL pages
> revert this to the default?

I see not reason. vdso/vsyscall don't contain any SSE code and also don't
do any callbacks to other user code. Except for signals and signals
already align the stack by themselves.

-Andi