Hello,
syzbot found the following crash on:
HEAD commit: 245a4300 Merge branch 'rcu/kcsan' into tip/locking/kcsan
git tree:
https://github.com/google/ktsan.git kcsan
console output:
https://syzkaller.appspot.com/x/log.txt?x=1690fac1e00000
kernel config:
https://syzkaller.appspot.com/x/.config?x=a38292766f8efdaa
dashboard link:
https://syzkaller.appspot.com/bug?extid=634339126df88fb0a7f6
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
CC: [
ax...@kernel.dk linux...@vger.kernel.org
linux-...@vger.kernel.org el...@google.com]
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by:
syzbot+634339...@syzkaller.appspotmail.com
==================================================================
BUG: KCSAN: data-race in wbt_done / wbt_issue
read to 0xffff88812a485230 of 8 bytes by interrupt on cpu 1:
wbt_is_tracked block/blk-wbt.c:46 [inline]
wbt_done+0x4d/0x1b0 block/blk-wbt.c:189
__rq_qos_done+0x4a/0x80 block/blk-rq-qos.c:45
rq_qos_done block/blk-rq-qos.h:153 [inline]
blk_mq_free_request+0x24c/0x360 block/blk-mq.c:510
__blk_mq_end_request block/blk-mq.c:539 [inline]
blk_mq_end_request+0x28f/0x2b0 block/blk-mq.c:548
lo_complete_rq+0x136/0x1a0 drivers/block/loop.c:487
blk_done_softirq+0x1eb/0x250 block/blk-softirq.c:37
__do_softirq+0x115/0x33f kernel/softirq.c:292
run_ksoftirqd+0x46/0x60 kernel/softirq.c:603
smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
write to 0xffff88812a485230 of 8 bytes by task 2505 on cpu 0:
wbt_issue block/blk-wbt.c:618 [inline]
wbt_issue+0xaf/0xf0 block/blk-wbt.c:603
__rq_qos_issue+0x4a/0x80 block/blk-rq-qos.c:54
rq_qos_issue block/blk-rq-qos.h:159 [inline]
blk_mq_start_request+0x32a/0x370 block/blk-mq.c:654
loop_queue_rq+0x64/0x280 drivers/block/loop.c:1911
blk_mq_dispatch_rq_list+0xbe9/0xe40 block/blk-mq.c:1238
blk_mq_do_dispatch_sched+0x11d/0x260 block/blk-mq-sched.c:115
blk_mq_sched_dispatch_requests+0x2b4/0x380 block/blk-mq-sched.c:211
__blk_mq_run_hw_queue+0xb7/0x160 block/blk-mq.c:1368
blk_mq_run_work_fn+0x57/0x70 block/blk-mq.c:1597
process_one_work+0x3d4/0x890 kernel/workqueue.c:2264
worker_thread+0xa0/0x800 kernel/workqueue.c:2410
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2505 Comm: kworker/0:1H Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: kblockd blk_mq_run_work_fn
==================================================================
---
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