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KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue

Status: auto-closed as invalid on 2020/12/04 12:11
Subsystems: block
[Documentation on labels]
First crash: 1394d, last: 1272d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue (2) block 16 1169d 1233d 0/26 auto-closed as invalid on 2021/03/17 22:19
upstream KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue (5) block 1 749d 749d 0/26 auto-closed as invalid on 2022/05/11 20:53
upstream KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue (4) block 2 798d 824d 0/26 auto-closed as invalid on 2022/03/23 12:22
upstream KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue (3) block 24 876d 1131d 0/26 auto-closed as invalid on 2022/01/04 22:32

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __blk_mq_sched_dispatch_requests / blk_mq_run_hw_queue

write to 0xffff8881025a5010 of 8 bytes by task 2979 on cpu 1:
 INIT_LIST_HEAD include/linux/list.h:36 [inline]
 list_splice_init include/linux/list.h:483 [inline]
 __blk_mq_sched_dispatch_requests+0x16a/0x2a0 block/blk-mq-sched.c:289
 blk_mq_sched_dispatch_requests+0x8f/0xf0 block/blk-mq-sched.c:341
 __blk_mq_run_hw_queue+0xee/0x1c0 block/blk-mq.c:1532
 __blk_mq_delay_run_hw_queue+0x17d/0x330 block/blk-mq.c:1609
 blk_mq_run_hw_queue+0x231/0x260 block/blk-mq.c:1662
 blk_mq_run_hw_queues block/blk-mq.c:1680 [inline]
 blk_mq_requeue_work+0x423/0x490 block/blk-mq.c:816
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
 worker_thread+0x635/0xb90 kernel/workqueue.c:2418
 kthread+0x1fa/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff8881025a5010 of 8 bytes by task 3190 on cpu 0:
 list_empty_careful include/linux/list.h:319 [inline]
 blk_mq_hctx_has_pending block/blk-mq.c:72 [inline]
 blk_mq_run_hw_queue+0x12e/0x260 block/blk-mq.c:1658
 blk_mq_submit_bio+0xd0d/0x1020 block/blk-mq.c:2205
 __submit_bio_noacct_mq block/blk-core.c:1026 [inline]
 submit_bio_noacct+0x77d/0x930 block/blk-core.c:1059
 submit_bio+0x1f3/0x360 block/blk-core.c:1129
 submit_bio_wait+0x79/0xc0 block/bio.c:1151
 blkdev_issue_flush+0xc3/0xe0 block/blk-flush.c:444
 ext4_sync_file+0x3e1/0x6a0 fs/ext4/fsync.c:177
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2723 [inline]
 ext4_buffered_write_iter+0x384/0x3d0 fs/ext4/file.c:278
 ext4_file_write_iter+0x45e/0x1090 fs/ext4/file.c:503
 call_write_iter include/linux/fs.h:1887 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4b0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x42a/0x780 fs/splice.c:686
 do_splice_from fs/splice.c:764 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:933
 splice_direct_to_actor+0x345/0x650 fs/splice.c:888
 do_splice_direct+0xf5/0x170 fs/splice.c:976
 do_sendfile+0x574/0xb70 fs/read_write.c:1257
 __do_sys_sendfile64 fs/read_write.c:1312 [inline]
 __se_sys_sendfile64 fs/read_write.c:1304 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1304
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3190 Comm: syz-executor.2 Not tainted 5.10.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (24):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/30 12:07 upstream 07e088730245 a6e3ac3b .config console log report info ci2-upstream-kcsan-gce
2020/10/25 04:23 upstream d76913908102 a1839e81 .config console log report info ci2-upstream-kcsan-gce
2020/10/24 20:09 upstream f11901ed723d a1839e81 .config console log report info ci2-upstream-kcsan-gce
2020/10/22 20:35 upstream 96485e446260 4e740c00 .config console log report info ci2-upstream-kcsan-gce
2020/10/22 15:10 upstream f804b3159482 be6b1582 .config console log report info ci2-upstream-kcsan-gce
2020/10/20 01:21 upstream bbe85027ce80 ff4a3345 .config console log report info ci2-upstream-kcsan-gce
2020/10/17 07:24 upstream 54a4c789ca80 6e262c73 .config console log report info ci2-upstream-kcsan-gce
2020/09/20 16:55 upstream 325d0eab4f31 9564d2e9 .config console log report info ci2-upstream-kcsan-gce
2020/08/30 07:05 upstream 1127b219ce94 d5a3ae1f .config console log report ci2-upstream-kcsan-gce
2020/08/29 01:58 upstream 96d454cd2c16 d5a3ae1f .config console log report ci2-upstream-kcsan-gce
2020/08/21 15:48 upstream da2968ff879b 1d75fe45 .config console log report ci2-upstream-kcsan-gce
2020/08/12 08:40 upstream bb5baaa9238e bb3e5fe6 .config console log report ci2-upstream-kcsan-gce
2020/08/06 09:16 upstream fffe3ae0ee84 0487ea6f .config console log report ci2-upstream-kcsan-gce
2020/08/02 23:45 upstream 142c3326b055 96dd3623 .config console log report ci2-upstream-kcsan-gce
2020/07/30 10:41 upstream 83bdc7275e62 b0947553 .config console log report ci2-upstream-kcsan-gce
2020/07/30 04:08 upstream 6ba1b005ffc3 233283a1 .config console log report ci2-upstream-kcsan-gce
2020/07/28 13:11 upstream 92ed30191993 cb93dc6a .config console log report ci2-upstream-kcsan-gce
2020/07/26 20:12 upstream 1ada9010e578 51265195 .config console log report ci2-upstream-kcsan-gce
2020/07/17 14:43 upstream 8882572675c1 9c812472 .config console log report ci2-upstream-kcsan-gce
2020/07/11 12:37 upstream 1df0d8960499 7ba05d2d .config console log report ci2-upstream-kcsan-gce
2020/07/08 15:41 upstream dcde237b9b0e 5962a2dc .config console log report ci2-upstream-kcsan-gce
2020/07/02 19:27 upstream cd77006e01b3 f30c14bf .config console log report ci2-upstream-kcsan-gce
2020/06/30 16:37 upstream 7c30b859a947 917afeaa .config console log report ci2-upstream-kcsan-gce
2020/06/30 10:03 upstream 7c30b859a947 917afeaa .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.