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KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each (3)

Status: auto-obsoleted due to no activity on 2024/01/05 10:53
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+c7b19bfba39d201a07b6@syzkaller.appspotmail.com
First crash: 100d, last: 92d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each (4) block 2 1d09h 29d 0/26 moderation: reported on 2024/02/02 09:31
upstream KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each (2) block 19 140d 259d 0/26 auto-obsoleted due to no activity on 2023/11/18 09:13
upstream KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each block 9 313d 391d 0/26 auto-obsoleted due to no activity on 2023/05/29 14:50

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each

write to 0xffff8881028aed60 of 4 bytes by task 29827 on cpu 0:
 __blk_mq_put_driver_tag block/blk-mq.h:339 [inline]
 blk_mq_put_driver_tag block/blk-mq.h:347 [inline]
 __blk_mq_requeue_request+0x130/0x2a0 block/blk-mq.c:1432
 blk_mq_handle_dev_resource block/blk-mq.c:1905 [inline]
 blk_mq_dispatch_rq_list+0x858/0x1090 block/blk-mq.c:2046
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline]
 blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline]
 __blk_mq_sched_dispatch_requests+0x5ec/0xd20 block/blk-mq-sched.c:309
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x2a4/0x4c0 block/blk-mq.c:2252
 blk_mq_get_tag+0x479/0x590 block/blk-mq-tag.c:170
 __blk_mq_alloc_requests+0x642/0x9e0 block/blk-mq.c:501
 blk_mq_get_new_requests block/blk-mq.c:2872 [inline]
 blk_mq_submit_bio+0x468/0xd90 block/blk-mq.c:2970
 __submit_bio+0x11c/0x350 block/blk-core.c:599
 __submit_bio_noacct_mq block/blk-core.c:678 [inline]
 submit_bio_noacct_nocheck+0x449/0x5e0 block/blk-core.c:707
 submit_bio_noacct+0x71c/0x8c0 block/blk-core.c:801
 submit_bio+0xb7/0xc0 block/blk-core.c:834
 ext4_io_submit+0x8a/0xa0 fs/ext4/page-io.c:378
 ext4_do_writepages+0xb3a/0x2100 fs/ext4/inode.c:2705
 ext4_writepages+0x15e/0x2e0 fs/ext4/inode.c:2774
 do_writepages+0x1c2/0x340 mm/page-writeback.c:2553
 filemap_fdatawrite_wbc+0xdb/0xf0 mm/filemap.c:387
 __filemap_fdatawrite_range mm/filemap.c:420 [inline]
 __filemap_fdatawrite mm/filemap.c:426 [inline]
 filemap_flush+0x95/0xc0 mm/filemap.c:453
 ext4_alloc_da_blocks+0x50/0x130 fs/ext4/inode.c:3077
 ext4_release_file+0x5f/0x1c0 fs/ext4/file.c:169
 __fput+0x299/0x630 fs/file_table.c:394
 ____fput+0x15/0x20 fs/file_table.c:422
 task_work_run+0x135/0x1a0 kernel/task_work.c:180
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0x604/0x16d0 kernel/exit.c:871
 do_group_exit+0x101/0x150 kernel/exit.c:1021
 get_signal+0xf4e/0x10a0 kernel/signal.c:2904
 arch_do_signal_or_restart+0x95/0x4b0 arch/x86/kernel/signal.c:309
 exit_to_user_mode_loop+0x6f/0xe0 kernel/entry/common.c:168
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 irqentry_exit_to_user_mode+0x9/0x20 kernel/entry/common.c:309
 irqentry_exit+0x12/0x40 kernel/entry/common.c:412
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

read to 0xffff8881028aed60 of 4 bytes by task 252 on cpu 1:
 blk_mq_find_and_get_req block/blk-mq-tag.c:260 [inline]
 bt_tags_iter block/blk-mq-tag.c:356 [inline]
 __sbitmap_for_each_set include/linux/sbitmap.h:281 [inline]
 sbitmap_for_each_set include/linux/sbitmap.h:302 [inline]
 bt_tags_for_each+0x2e2/0x500 block/blk-mq-tag.c:391
 __blk_mq_all_tag_iter block/blk-mq-tag.c:402 [inline]
 blk_mq_tagset_busy_iter+0x114/0x150 block/blk-mq-tag.c:446
 scsi_host_busy+0x4f/0x80 drivers/scsi/hosts.c:604
 scsi_host_queue_ready drivers/scsi/scsi_lib.c:1341 [inline]
 scsi_queue_rq+0x310/0x1a30 drivers/scsi/scsi_lib.c:1735
 blk_mq_dispatch_rq_list+0x2d9/0x1090 block/blk-mq.c:2037
 __blk_mq_sched_dispatch_requests+0x1ce/0xd20 block/blk-mq-sched.c:301
 blk_mq_sched_dispatch_requests+0x99/0x100 block/blk-mq-sched.c:333
 blk_mq_run_hw_queue+0x2a4/0x4c0 block/blk-mq.c:2252
 blk_mq_run_hw_queues+0x161/0x1e0 block/blk-mq.c:2301
 blk_mq_requeue_work+0x408/0x430 block/blk-mq.c:1498
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

value changed: 0x00001b0a -> 0xffffffff

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 252 Comm: kworker/1:1H Not tainted 6.7.0-rc3-syzkaller-00048-ge8f60209d6cf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: kblockd blk_mq_requeue_work
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/12/01 10:52 upstream e8f60209d6cf f819d6f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each
2023/11/23 16:25 upstream 9b6de136b5f0 fc59b78e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __blk_mq_requeue_request / bt_tags_for_each
* Struck through repros no longer work on HEAD.