Re: [PATCH 1/3] x86/xen: Avoid fast syscall path for Xen PV guests

From: Borislav Petkov
Date: Thu Nov 19 2015 - 07:08:37 EST

On Wed, Nov 18, 2015 at 12:21:56PM -0800, Andy Lutomirski wrote:
> Could we make this a little less subtle:
> ALTERNATIVE "testl %eax, %eax; lz .Lsyscall_32_done", "jmp
> .Lsyscasll_32_done", X86_FEATURE_XENPV
> Borislav, what do you think?

I don't mind either.

I would've said your version doesn't touch %eax so the result in there
might be useful for callers but all paths do overwrite it, AFAICT.


SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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