On Tue, Jul 03, 2018 at 03:20:31PM -0600, Jens Axboe wrote:
On 7/3/18 3:15 PM, Jens Axboe wrote:
commit cd4a4ae4683dc2e09380118e205e057896dcda2b upstream.
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.
We're running fio tests and the tasks get stuck in a D state forever when systemd-udevd tries to read the partition table. This patch solves it. Please apply to 4.17 stable.
Reported-by: syzbot+c4f9cebf9d651f6e54de@syzkaller.appspotmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Alexandru Moise 00moses.alexander00@gmail.com
WTF? Please don't send out emails with my name. Ever.
Crap, that's the last thing I intended. I need to set fire to my scripts now, along with my lazy eye. Please accept my most sincere apologies for this stupid mistake.
../Alex
-- Jens Axboe