lkml.org 
[lkml]   [2012]   [Nov]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH] Avoid dead lock of console related locks in panic case
Date
> What I actually meant was: can "this" CPU avoid stopping other CPUs so early?  If we stop the other CPUs when this CPU is ready to
> stop itself then there will never be such deadlocks.

Let me explain my opinion.
When we focus on the deadlock only, the code will be simple by moving smp_send_stop() at the end of panic().

But, panic situation is not normal.
I don't think that keeping running multiple cpus is safe, because they may touch corrupted data/variables and unnecessary
panic/BUG() may happen.

IMO, cpus should be stopped "as early as" possible when panic happens.
And then panic() has to take minimal steps with a single cpu.
- output messages
- kicking troubleshooting features like kdump/kmsg_dump

Seiji




\
 
 \ /
  Last update: 2012-12-01 02:41    [W:0.044 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site