| Date | Fri, 25 Apr 2014 12:45:30 -0400 | From | Steven Rostedt <> | Subject | Re: [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
|