On 2/20/20 11:45 AM, Glauber Costa wrote: > On Thu, Feb 20, 2020 at 12:28 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >> >> On 2/20/20 9:52 AM, Glauber Costa wrote: >>> On Thu, Feb 20, 2020 at 11:39 AM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>> >>>> On 2/20/20 9:34 AM, Glauber Costa wrote: >>>>> On Thu, Feb 20, 2020 at 11:29 AM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>>>> >>>>>> On 2/20/20 9:17 AM, Jens Axboe wrote: >>>>>>> On 2/20/20 7:19 AM, Glauber Costa wrote: >>>>>>>> Hi there, me again >>>>>>>> >>>>>>>> Kernel is at 043f0b67f2ab8d1af418056bc0cc6f0623d31347 >>>>>>>> >>>>>>>> This test is easier to explain: it essentially issues a connect and a >>>>>>>> shutdown right away. >>>>>>>> >>>>>>>> It currently fails due to no fault of io_uring. But every now and then >>>>>>>> it crashes (you may have to run more than once to get it to crash) >>>>>>>> >>>>>>>> Instructions are similar to my last test. >>>>>>>> Except the test to build is now "tests/unit/connect_test" >>>>>>>> Code is at git@xxxxxxxxxx:glommer/seastar.git branch io-uring-connect-crash >>>>>>>> >>>>>>>> Run it with ./build/release/tests/unit/connect_test -- -c1 >>>>>>>> --reactor-backend=uring >>>>>>>> >>>>>>>> Backtrace attached >>>>>>> >>>>>>> Perfect thanks, I'll take a look! >>>>>> >>>>>> Haven't managed to crash it yet, but every run complains: >>>>>> >>>>>> got to shutdown of 10 with refcnt: 2 >>>>>> Refs being all dropped, calling forget for 10 >>>>>> terminate called after throwing an instance of 'fmt::v6::format_error' >>>>>> what(): argument index out of range >>>>>> unknown location(0): fatal error: in "unixdomain_server": signal: SIGABRT (application abort requested) >>>>>> >>>>>> Not sure if that's causing it not to fail here. >>>>> >>>>> Ok, that means it "passed". (I was in the process of figuring out >>>>> where I got this wrong when I started seeing the crashes) >>>> >>>> Can you do, in your kernel dir: >>>> >>>> $ gdb vmlinux >>>> [...] >>>> (gdb) l *__io_queue_sqe+0x4a >>>> >>>> and see what it says? >>> >>> 0xffffffff81375ada is in __io_queue_sqe (fs/io_uring.c:4814). >>> 4809 struct io_kiocb *linked_timeout; >>> 4810 struct io_kiocb *nxt = NULL; >>> 4811 int ret; >>> 4812 >>> 4813 again: >>> 4814 linked_timeout = io_prep_linked_timeout(req); >>> 4815 >>> 4816 ret = io_issue_sqe(req, sqe, &nxt, true); >>> 4817 >>> 4818 /* >>> >>> (I am not using timeouts, just async_cancel) >> >> Can't seem to hit it here, went through thousands of iterations... >> I'll keep trying. >> >> If you have time, you can try and enable CONFIG_KASAN=y and see if >> you can hit it with that. > > I can > > Attaching full dmesg Can you try the latest? It's sha d8154e605f84. Before you do, can you do the lookup on __io_queue_sqe+0x639 with gdb? -- Jens Axboe