On 1/5/22 7:26 AM, Eric Biggers wrote: > On Thu, Dec 09, 2021 at 02:46:45PM -0700, Jens Axboe wrote: >> On 12/9/21 11:00 AM, Linus Torvalds wrote: >>> On Wed, Dec 8, 2021 at 5:06 PM Eric Biggers <ebiggers@xxxxxxxxxx> wrote: >>>> >>>> Careful review is appreciated; the aio poll code is very hard to work >>>> with, and it doesn't appear to have many tests. I've verified that it >>>> passes the libaio test suite, which provides some coverage of poll. >>>> >>>> Note, it looks like io_uring has the same bugs as aio poll. I haven't >>>> tried to fix io_uring. >>> >>> I'm hoping Jens is looking at the io_ring case, but I'm also assuming >>> that I'll just get a pull request for this at some point. >> >> Yes, when I saw this original posting I did discuss it with Pavel as >> well, and we agree that the same issue exists there. Which isn't too >> surprising, as that's where the io_uring poll code from originally. >> > > Jens, any update on fixing the io_uring version of the bug? Note, > syzbot has managed to use io_uring poll to hit the WARN_ON_ONCE() that > I added in __wake_up_pollfree(), which proves that it is broken. There are two parts to this, first part is queued up for 5.17 for a few weeks. Work in progress... -- Jens Axboe