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. Any objection to adding your test cases to the liburing regression suite? -- Jens Axboe
