On 02/25/2016, 08:23 PM, Steven Rostedt wrote: > On Thu, 25 Feb 2016 11:09:35 -0800 > Linus Torvalds <torva...@linux-foundation.org> wrote: > > >> Jiri, were you messing around with tracing when this happened? Or >> maybe shutting down CPU's? There was a RCU locking problem with CPU >> shutdown, maybe this is one of the symptoms. The fix for that is >> recent, and not in 4.4.2. >> >> Adding Steven Rostedt to the cc. Steven, does that look like a possible case? > > Possible: yes. Likely: no > > The recent fix would require shutting down a CPU at the same time as a > tracepoint is enabled or disabled. Rather difficult to hit, but easier > on a virtual machine. If Jiri was not enabling/disabling tracepoints or > shutting down CPUs, then it would not be the bug.
As this is an automatic build, I very doubt a CPU was offlined or tracepoints enabled. So I see it even less unlikely this to happen concurrently. > But as the comm of the bug is gdb and this running on a virtual > machine, I think the bug may be elsewhere. Corrupt stack possibly? Seems so (broken stack frame pointer link), as is indicated in other e-mail. thanks, -- js suse labs
