3.14-rc2 XFS backtrace because irqs_disabled.

[Oleg Nesterov]

On 02/14, Christoph Hellwig wrote:
>
> Might aswell stick the discmiss into what was dequeue_signal_lock().
> Which at that point should get a saner name (maybe thread_dequeue_signal ?)
> and lose all argument except maybe task_struct

No, task_struct argument should die, I think. It is misleading.

spin_lock(tsk->sighand->siglock) is simply wrong unless tsk == current.

And dequeue_signal() assumes that tsk == current too, otherwise
recalc_sigpending() is wrong.

Oleg.