lkml.org 
[lkml]   [2017]   [Oct]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC V2] printk: add warning while drop partial text in msg
On (10/18/17 01:10), pierre kuo wrote:
[..]
> > Well, it might get quite complicated, see printk_safe_flush_buffer().
>
> BTW, after checking printk_safe_flush_buffer() and related functions,
> we have one question:
> a) Why in printk_safe_log_store(), we need to use atomic_xxxx operation in it?

because IRQ flush work iterates all CPUs and modifies CPUs' buffer state,
and this easily can race with printk_safe() or printk_nmi() on some of the
CPUs.

-ss

\
 
 \ /
  Last update: 2017-10-22 17:06    [W:0.080 / U:0.980 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site