[lkml]   [2012]   [Jul]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [patch] x86, avx: don't use avx instructions with "noxsave" boot param
On 07/31/2012 09:27 AM, Suresh Siddha wrote:
> On Mon, 2012-07-30 at 21:33 -0700, H. Peter Anvin wrote:
>> I'm wondering if we shouldn't just kill the affected CPUID bits if osxsave is off...
> Yes, I considered clearing AVX bit (and any future xsave feature bits)
> as part of the parsing "noxsave" parameter in x86_xsave_setup().
> But thought checking for osxsave was more explicit and there are not
> many places using avx code. Also, this follows the SDM guidelines and
> sets a nice precedent for someone (app's) to follow in future.
> I am ok either way!

My main reason for thinking that it would be good to clear the bits is
that it plays a lot nicer with alternatives and with static_cpu_has().


H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

 \ /
  Last update: 2012-08-01 00:21    [W:0.100 / U:1.588 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site