lkml.org 
[lkml]   [2010]   [Jul]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 134/149] x86, paravirt: Add a global synchronization point for pvclock
On 07/14/2010 10:30 AM, H. Peter Anvin wrote:
> If gcc ever starts reordering volatile operations, including "asm
> volatile", the kernel will break, and will be unfixable. Just about
> every single driver will break. All over the kernel we're explicitly or
> implicitly making the assumption that volatile operations are strictly
> ordered by the compiler with respect to each other.
>

Can you give an example? All the cases I've seen rely on the ordering
properties of "memory" clobbers, which is sound. (And volatile
variables are a completely unrelated issue, of course.)

J


\
 
 \ /
  Last update: 2010-07-14 19:37    [W:0.543 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site