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KCSAN: data-race in sbitmap_queue_clear / sbitmap_queue_clear (2)

Status: auto-closed as invalid on 2020/12/21 11:46
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+f41b108210915b7bfb51@syzkaller.appspotmail.com
First crash: 1270d, last: 1251d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in sbitmap_queue_clear / sbitmap_queue_clear (3) block 5 897d 903d 20/26 fixed on 2022/03/08 16:11
upstream KCSAN: data-race in sbitmap_queue_clear / sbitmap_queue_clear block 36 1533d 1635d 0/26 auto-closed as invalid on 2020/04/14 03:40

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

write to 0xffffe8ffffd28494 of 4 bytes by interrupt on cpu 1:
 sbitmap_queue_clear+0xca/0xf0 lib/sbitmap.c:588
 blk_mq_put_tag+0x82/0x90 block/blk-mq-tag.c:188
 __blk_mq_free_request+0x14e/0x1c0 block/blk-mq.c:497
 blk_mq_free_request+0x2bd/0x330 block/blk-mq.c:531
 __blk_mq_end_request+0x214/0x230 block/blk-mq.c:555
 blk_mq_end_request+0x37/0x50 block/blk-mq.c:564
 lo_complete_rq+0xca/0x180 drivers/block/loop.c:500
 blk_done_softirq+0x145/0x190 block/blk-mq.c:586
 __do_softirq+0x12c/0x2b1 kernel/softirq.c:298
 run_ksoftirqd+0x13/0x20 kernel/softirq.c:653
 smpboot_thread_fn+0x34f/0x520 kernel/smpboot.c:165
 kthread+0x1fa/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

write to 0xffffe8ffffd28494 of 4 bytes by interrupt on cpu 0:
 sbitmap_queue_clear+0xca/0xf0 lib/sbitmap.c:588
 blk_mq_put_tag+0x82/0x90 block/blk-mq-tag.c:188
 __blk_mq_free_request+0x14e/0x1c0 block/blk-mq.c:497
 blk_mq_free_request+0x2bd/0x330 block/blk-mq.c:531
 __blk_mq_end_request+0x214/0x230 block/blk-mq.c:555
 blk_mq_end_request+0x37/0x50 block/blk-mq.c:564
 lo_complete_rq+0xca/0x180 drivers/block/loop.c:500
 blk_done_softirq+0x145/0x190 block/blk-mq.c:586
 __do_softirq+0x12c/0x2b1 kernel/softirq.c:298
 run_ksoftirqd+0x13/0x20 kernel/softirq.c:653
 smpboot_thread_fn+0x34f/0x520 kernel/smpboot.c:165
 kthread+0x1fa/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10 Comm: ksoftirqd/0 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/11 22:12 upstream eccc87672492 cca87986 .config console log report info ci2-upstream-kcsan-gce
2020/10/26 11:51 upstream 3650b228f83a a7aac492 .config console log report info ci2-upstream-kcsan-gce
2020/10/26 08:50 upstream 3650b228f83a a1839e81 .config console log report info ci2-upstream-kcsan-gce
2020/10/23 17:36 upstream f9893351acae 4e740c00 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.