Re: [PATCH] aio: Fix incorrect usage of eventfd_signal_allowed()

From: Eric Biggers
Date: Fri Dec 10 2021 - 13:53:56 EST


On Tue, Dec 07, 2021 at 03:33:47PM -0800, Eric Biggers wrote:
> On Mon, Sep 13, 2021 at 07:19:28PM +0800, Xie Yongji wrote:
> > We should defer eventfd_signal() to the workqueue when
> > eventfd_signal_allowed() return false rather than return
> > true.
> >
> > Fixes: b542e383d8c0 ("eventfd: Make signal recursion protection a task bit")
> > Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
> > ---
> > fs/aio.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/fs/aio.c b/fs/aio.c
> > index 51b08ab01dff..8822e3ed4566 100644
> > --- a/fs/aio.c
> > +++ b/fs/aio.c
> > @@ -1695,7 +1695,7 @@ static int aio_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
> > list_del(&iocb->ki_list);
> > iocb->ki_res.res = mangle_poll(mask);
> > req->done = true;
> > - if (iocb->ki_eventfd && eventfd_signal_allowed()) {
> > + if (iocb->ki_eventfd && !eventfd_signal_allowed()) {
> > iocb = NULL;
> > INIT_WORK(&req->work, aio_poll_put_work);
> > schedule_work(&req->work);
> > --
> > 2.11.0
> >
>
> Since I was just working with this file...:
>
> Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> I don't know who is taking aio fixes these days, but whoever does so probably
> should take this one at the same time as mine
> (https://lore.kernel.org/linux-fsdevel/20211207095726.169766-1-ebiggers@xxxxxxxxxx).

Apparently no one is, so I've included this patch in the pull request I've sent
(https://lore.kernel.org/r/YbOdV8CPbyPAF234@sol.localdomain).

- Eric