lkml.org 
[lkml]   [2014]   [Apr]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC v3 1/9] sysrq: Implement __handle_sysrq_nolock to avoid recursive locking in kdb
On Fri, 25 Apr 2014 17:29:22 +0100
Daniel Thompson <daniel.thompson@linaro.org> wrote:

> If kdb is triggered using SysRq-g then any use of the sr command results
> in the SysRq key table lock being recursively acquired, killing the debug
> session. That patch resolves the problem by introducing a _nolock
> alternative for __handle_sysrq.
>
> Strictly speaking this approach risks racing on the key table when kdb is
> triggered by something other than SysRq-g however in that case any other
> CPU involved should release the spin lock before kgdb parks the slave
> CPUs.

Is that case documented somewhere in the code comments?

-- Steve


\
 
 \ /
  Last update: 2014-04-25 19:41    [W:0.380 / U:0.128 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site