On Wed, Oct 30, 2024 at 03:13:09PM +0800, Ming Lei wrote: > On Wed, Oct 30, 2024 at 02:45:03PM +0800, Lai, Yi wrote: > > Hi Ming, > > > > Greetings! > > > > I used Syzkaller and found that there is possible deadlock in __submit_bio in linux-next next-20241029. > > > > After bisection and the first bad commit is: > > " > > f1be1788a32e block: model freeze & enter queue as lock for supporting lockdep > > " > > > > All detailed into can be found at: > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio > > Syzkaller repro code: > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio/repro.c > > Syzkaller repro syscall steps: > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio/repro.prog > > Syzkaller report: > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio/repro.report > > Kconfig(make olddefconfig): > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio/kconfig_origin > > Bisect info: > > https://github.com/laifryiee/syzkaller_logs/tree/main/241029_183511___submit_bio/bisect_info.log > > bzImage: > > https://github.com/laifryiee/syzkaller_logs/raw/refs/heads/main/241029_183511___submit_bio/bzImage_6fb2fa9805c501d9ade047fc511961f3273cdcb5 > > Issue dmesg: > > https://github.com/laifryiee/syzkaller_logs/blob/main/241029_183511___submit_bio/6fb2fa9805c501d9ade047fc511961f3273cdcb5_dmesg.log > > > > " > > [ 22.219103] 6.12.0-rc5-next-20241029-6fb2fa9805c5 #1 Not tainted > > [ 22.219512] ------------------------------------------------------ > > [ 22.219827] repro/735 is trying to acquire lock: > > [ 22.220066] ffff888010f1a768 (&q->q_usage_counter(io)#25){++++}-{0:0}, at: __submit_bio+0x39f/0x550 > > [ 22.220568] > > [ 22.220568] but task is already holding lock: > > [ 22.220884] ffffffff872322a0 (fs_reclaim){+.+.}-{0:0}, at: __alloc_pages_slowpath.constprop.0+0x76b/0x21e0 > > [ 22.221453] > > [ 22.221453] which lock already depends on the new lock. > > [ 22.221453] > > [ 22.221862] > > [ 22.221862] the existing dependency chain (in reverse order) is: > > [ 22.222247] > > [ 22.222247] -> #1 (fs_reclaim){+.+.}-{0:0}: > > [ 22.222630] lock_acquire+0x80/0xb0 > > [ 22.222920] fs_reclaim_acquire+0x116/0x160 > > [ 22.223244] __kmalloc_cache_node_noprof+0x59/0x470 > > [ 22.223528] blk_mq_init_tags+0x79/0x1a0 > > [ 22.223771] blk_mq_alloc_map_and_rqs+0x1f4/0xdd0 > > [ 22.224127] blk_mq_init_sched+0x33d/0x6d0 > > [ 22.224376] elevator_init_mq+0x2b2/0x400 > > It should be addressed by the following patch: > > https://lore.kernel.org/linux-block/ZyEGLdg744U_xBjp@fedora/ > I have applied proposed fix patch on top of next-20241029. Issue can still be reproduced. It seems the dependency chain is different from Marek's log and mine. > Thanks, > Ming >
