lkml.org 
[lkml]   [2014]   [Sep]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] x86 : Ensure X86_FLAGS_NT is cleared on syscall entry
On Mon, Sep 29, 2014 at 11:59 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> On Mon, 29 Sep 2014, Andy Lutomirski wrote:
>> Presumably interrupt delivery clears NT. I haven't spotted where that's
>> documented yet.
>
> Nope, that's unrelated.

If it weren't the case, then we'd be totally screwed. Fortunately, it
is. I found it: SDM Volume 3 6.12.1.2 says:

(On calls to exception and interrupt
handlers, the processor also clears the VM, RF, and NT flags in the
EFLAGS register,
after they are saved on the stack.)

--Andy


\
 
 \ /
  Last update: 2014-09-29 21:21    [W:0.123 / U:1.112 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site