• Jens Axboe's avatar
    block: don't use blocking queue entered for recursive bio submits · cd4a4ae4
    Jens Axboe authored
    If we end up splitting a bio and the queue goes away between
    the initial submission and the later split submission, then we
    can block forever in blk_queue_enter() waiting for the reference
    to drop to zero. This will never happen, since we already hold
    a reference.
    
    Mark a split bio as already having entered the queue, so we can
    just use the live non-blocking queue enter variant.
    
    Thanks to Tetsuo Handa for the analysis.
    
    Reported-by: syzbot+c4f9cebf9d651f6e54de@syzkaller.appspotmail.com
    Signed-off-by: 's avatarJens Axboe <axboe@kernel.dk>
    cd4a4ae4