lkml.org 
[lkml]   [2015]   [Apr]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 01/16] x86, fpu: wrap get_xsave_addr() to make it safer
On Wed, Apr 22, 2015 at 05:32:45PM +0200, Oleg Nesterov wrote:
> How? I am certainly missing you point... OK, please forge about FPU.
> Consider this code:
>
> tsk = current;
> for (;;)
> BUG_ON(tsk != current);
>
> it doesn't need to disable preemption. We do not care if CPU switches
> to another thread, even if this thread executes the same code. Because
> its tsk/current will differ, but "tsk == current" will be still true.
>
> Could you please spell?

Bah, forget what I said. tglx schooled me on IRC. We always do get
called with tsk == current. Sorry for the confusion...

> See above... used_math() should be correct because we know that tsk==current,
> but I agree that tsk_used_math(tsk) looks better.

Right, and it is clear what's going on, even to lusers like me.

Thanks for teaching me guys.

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
--


\
 
 \ /
  Last update: 2015-04-22 18:21    [W:0.089 / U:1.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site