On 4/8/20 8:50 PM, Dmitry Kadashev wrote: > On Wed, Apr 8, 2020 at 11:26 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >> >> On 4/8/20 9:12 AM, Dmitry Kadashev wrote: >>> On Wed, Apr 8, 2020 at 10:49 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>> >>>> On 4/8/20 8:41 AM, Dmitry Kadashev wrote: >>>>> On Wed, Apr 8, 2020 at 10:36 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>>>> >>>>>> On 4/8/20 8:30 AM, Dmitry Kadashev wrote: >>>>>>> On Wed, Apr 8, 2020 at 10:19 PM Jens Axboe <axboe@xxxxxxxxx> wrote: >>>>>>>> >>>>>>>> On 4/8/20 7:51 AM, Dmitry Kadashev wrote: >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> io_uring's openat seems to produce FDs that are incompatible with >>>>>>>>> large files (>2GB). If a file (smaller than 2GB) is opened using >>>>>>>>> io_uring's openat then writes -- both using io_uring and just sync >>>>>>>>> pwrite() -- past that threshold fail with EFBIG. If such a file is >>>>>>>>> opened with sync openat, then both io_uring's writes and sync writes >>>>>>>>> succeed. And if the file is larger than 2GB then io_uring's openat >>>>>>>>> fails right away, while the sync one works. >>>>>>>>> >>>>>>>>> Kernel versions: 5.6.0-rc2, 5.6.0. >>>>>>>>> >>>>>>>>> A couple of reproducers attached, one demos successful open with >>>>>>>>> failed writes afterwards, and another failing open (in comparison with >>>>>>>>> sync calls). >>>>>>>>> >>>>>>>>> The output of the former one for example: >>>>>>>>> >>>>>>>>> *** sync openat >>>>>>>>> openat succeeded >>>>>>>>> sync write at offset 0 >>>>>>>>> write succeeded >>>>>>>>> sync write at offset 4294967296 >>>>>>>>> write succeeded >>>>>>>>> >>>>>>>>> *** sync openat >>>>>>>>> openat succeeded >>>>>>>>> io_uring write at offset 0 >>>>>>>>> write succeeded >>>>>>>>> io_uring write at offset 4294967296 >>>>>>>>> write succeeded >>>>>>>>> >>>>>>>>> *** io_uring openat >>>>>>>>> openat succeeded >>>>>>>>> sync write at offset 0 >>>>>>>>> write succeeded >>>>>>>>> sync write at offset 4294967296 >>>>>>>>> write failed: File too large >>>>>>>>> >>>>>>>>> *** io_uring openat >>>>>>>>> openat succeeded >>>>>>>>> io_uring write at offset 0 >>>>>>>>> write succeeded >>>>>>>>> io_uring write at offset 4294967296 >>>>>>>>> write failed: File too large >>>>>>>> >>>>>>>> Can you try with this one? Seems like only openat2 gets it set, >>>>>>>> not openat... >>>>>>> >>>>>>> I've tried specifying O_LARGEFILE explicitly, that did not change the >>>>>>> behavior. Is this good enough? Much faster for me to check this way >>>>>>> that rebuilding the kernel. But if necessary I can do that. >>>>>> >>>>>> Not sure O_LARGEFILE settings is going to do it for x86-64, the patch >>>>>> should fix it though. Might have worked on 32-bit, though. >>>>> >>>>> OK, will test. >>>> >>>> Great, thanks. FWIW, tested here, and it works for me. >>> >>> Great, will post results tomorrow. >> >> Thanks! > > With the patch applied it works perfectly, thanks. Thanks for testing! -- Jens Axboe
