Re: [PATCH 1/2] x86/xen/pvh: Set up percpu for stack canary in 32-bit kernel entry

[Hou Wenlong]

On Mon, Oct 23, 2023 at 08:02:02PM +0800, Andy Shevchenko wrote:
> On Mon, Oct 23, 2023 at 12:10 PM Hou Wenlong
> <houwenlong.hwl@xxxxxxxxxxxx> wrote:
> >
> > In a 32-bit SMP kernel, the stack canary is a percpu variable accessed
> > as %fs:__stack_chk_guard. However, the ABI for PVH entry does not
> > specify the %fs register state. It currently works because the initial
> > %fs register is 0x10 for QEMU, which is the same as $PVH_DS_SEL.
> 
> > %However, for added safety, the percpu should be set up explicitly
> > %before calling xen_prepare_pvh(), which accesses the stack canary.
> 
> Stray leading % in two lines above.
>
Oh, sorry for that. It was added by mistake by my editor, and I didn't
carefully review it before sending.
 
Thanks!

> -- 
> With Best Regards,
> Andy Shevchenko