Re: [patch V4 part 1 05/36] x86/entry: Flip _TIF_SIGPENDING and _TIF_NOTIFY_RESUME handling

From: Peter Zijlstra
Date: Thu May 14 2020 - 05:20:35 EST


On Wed, May 13, 2020 at 10:51:53PM -0400, Mathieu Desnoyers wrote:

> Yes, I'm very well aware of this. But the patch commit message states:
>
> "Make sure task_work runs before any kind of userspace -- very much
> including signals -- is invoked."
>
> which seems to imply that "userspace" can be "invoked" before the task_work
> runs. Which makes no sense whatsoever. Hence my confused state.

I initially missed the run_task_work in the signal handling maze. Then
later figured this order still made more sense, but apparently there's
an actual problem.

I've no problem with the patch getting dropped.