Re: [PATCH] fs: process fput task_work with TWA_SIGNAL

[Sedat Dilek]

On Fri, Jan 8, 2021 at 4:56 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
>
> On 1/7/21 3:17 PM, Doug Anderson wrote:
> > Hi,
> >
> > On Tue, Jan 5, 2021 at 10:30 AM Jens Axboe <axboe@xxxxxxxxx> wrote:
> >>
> >> Song reported a boot regression in a kvm image with 5.11-rc, and bisected
> >> it down to the below patch. Debugging this issue, turns out that the boot
> >> stalled when a task is waiting on a pipe being released. As we no longer
> >> run task_work from get_signal() unless it's queued with TWA_SIGNAL, the
> >> task goes idle without running the task_work. This prevents ->release()
> >> from being called on the pipe, which another boot task is waiting on.
> >>
> >> Use TWA_SIGNAL for the file fput work to ensure it's run before the task
> >> goes idle.
> >>
> >> Fixes: 98b89b649fce ("signal: kill JOBCTL_TASK_WORK")
> >> Reported-by: Song Liu <songliubraving@xxxxxx>
> >> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
> >
> > I just spend a bit of time bisecting and landed on commit 98b89b649fce
> > ("signal: kill JOBCTL_TASK_WORK") causing my failure to bootup
> > mainline.  Your patch fixes my problem.  I haven't done any analysis
> > of the code--just testing, thus:
> >
> > Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
>
> Thanks, adding your Tested-by.
>

I have this in my patch-series since it appeared in [1].

Feel free to add my:

   Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx> # LLVM/Clang version 11.0.1

- Sedat -

[1] https://git.kernel.dk/cgit/linux-block/log/?h=task_work

- Sedat -