syzbot


KCSAN: data-race in __xa_clear_mark / xas_find_marked (2)

Status: moderation: reported on 2021/06/26 18:58
Subsystems: mm fs
[Documentation on labels]
Reported-by: syzbot+03743c59b799c7b55cd4@syzkaller.appspotmail.com
First crash: 1505d, last: 1d00h
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __xa_clear_mark / xas_find_marked fs mm 6 558 1505d 1806d 0/29 closed as invalid on 2021/06/07 13:50

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

read-write to 0xffff8881072e4fe0 of 8 bytes by interrupt on cpu 1:
 instrument_read_write include/linux/instrumented.h:55 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:84 [inline]
 ___test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:114 [inline]
 node_clear_mark lib/xarray.c:102 [inline]
 xas_clear_mark lib/xarray.c:922 [inline]
 __xa_clear_mark+0xf5/0x1e0 lib/xarray.c:2097
 __folio_end_writeback+0x177/0x470 mm/page-writeback.c:3024
 folio_end_writeback+0x71/0x3d0 mm/filemap.c:1660
 end_buffer_async_write+0x156/0x1f0 fs/buffer.c:419
 end_bio_bh_io_sync+0x79/0xa0 fs/buffer.c:2783
 bio_endio+0x377/0x410 block/bio.c:1645
 blk_update_request+0x336/0x730 block/blk-mq.c:987
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1149
 lo_complete_rq+0x98/0x140 drivers/block/loop.c:304
 blk_complete_reqs block/blk-mq.c:1224 [inline]
 blk_done_softirq+0x77/0xb0 block/blk-mq.c:1229
 handle_softirqs+0xb7/0x290 kernel/softirq.c:579
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:968
 smpboot_thread_fn+0x328/0x530 kernel/smpboot.c:164
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff8881072e4fe0 of 8 bytes by task 3305 on cpu 0:
 xas_find_chunk include/linux/xarray.h:1752 [inline]
 xas_find_marked+0x218/0x620 lib/xarray.c:1510
 find_get_entry+0x5d/0x380 mm/filemap.c:2038
 filemap_get_folios_tag+0x92/0x210 mm/filemap.c:2306
 __filemap_fdatawait_range mm/filemap.c:530 [inline]
 filemap_write_and_wait_range+0x1d3/0x340 mm/filemap.c:700
 filemap_write_and_wait include/linux/pagemap.h:68 [inline]
 sync_blockdev+0x35/0x50 block/bdev.c:260
 sync_filesystem+0x162/0x190 fs/sync.c:70
 generic_shutdown_super+0x44/0x210 fs/super.c:622
 kill_block_super+0x2a/0x70 fs/super.c:1755
 ext4_kill_sb+0x42/0x80 fs/ext4/super.c:7391
 deactivate_locked_super+0x75/0x1c0 fs/super.c:474
 deactivate_super+0x97/0xa0 fs/super.c:507
 cleanup_mnt+0x269/0x2e0 fs/namespace.c:1417
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1424
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000002201022 -> 0x0000000002200000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3305 Comm: syz-executor Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================

Crashes (4719):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/21 03:30 upstream 89be9a83ccf1 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/20 13:22 upstream f4a40a4282f4 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/20 00:09 upstream bf61759db409 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/19 11:37 upstream 4871b7cb27f4 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/18 03:35 upstream 6832a9317eee 88248e14 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/17 15:12 upstream e2291551827f 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/17 01:10 upstream e2291551827f 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/16 20:43 upstream 155a3c003e55 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/16 07:36 upstream 155a3c003e55 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/15 05:27 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/14 11:10 upstream 347e9f5043c8 d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/14 08:33 upstream 347e9f5043c8 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/13 19:05 upstream 5d5d62298b8b 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/12 22:20 upstream 3f31a806a62e 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/12 08:45 upstream 379f604cc3dc 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/11 20:18 upstream 40f92e79b0aa 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/10 19:01 upstream bc9ff192a6c9 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/10 17:19 upstream 8c2e52ebbe88 3cda49cf .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/10 03:30 upstream 8c2e52ebbe88 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/09 22:23 upstream 8c2e52ebbe88 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/09 08:40 upstream 733923397fd9 f4e5e155 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/09 06:35 upstream 733923397fd9 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/08 17:06 upstream d006330be3f7 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/08 14:50 upstream d7b8f8e20813 4d9fdfa4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/07 02:59 upstream d7b8f8e20813 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/06 10:45 upstream 1f988d0788f5 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/05 21:02 upstream 05df91921da6 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/05 07:18 upstream a79a588fc176 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/05 04:07 upstream a79a588fc176 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/04 14:54 upstream 4c06e63b9203 d869b261 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/03 22:33 upstream 17bbde2e1716 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/03 17:24 upstream 17bbde2e1716 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/03 04:31 upstream b4911fb0b060 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/02 18:53 upstream b4911fb0b060 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/02 04:23 upstream 66701750d556 bc80e4f0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/01 15:06 upstream 66701750d556 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/07/01 01:09 upstream 66701750d556 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/30 17:32 upstream d0b3b7b22dfa 6e83b42d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/30 02:59 upstream d0b3b7b22dfa fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/28 23:13 upstream ded779017ad7 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/27 22:44 upstream 67a993863163 fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/27 16:41 upstream 67a993863163 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/26 13:18 upstream ee88bddf7f2f 803ce19b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/26 08:54 upstream ee88bddf7f2f 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/25 19:26 upstream 92ca6c498a5e 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/25 01:53 upstream 7595b66ae9de 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/24 18:31 upstream 78f4e737a53e 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/24 00:01 upstream 78f4e737a53e e2f27c35 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/23 11:43 upstream 86731a2a651e d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/06/22 21:01 upstream b67ec639010f d6cdfb8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2021/06/26 05:21 upstream b7050b242430 9d2ab5df .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2021/06/22 18:45 upstream 0c18f29aae7c aba2b2fb .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2021/06/07 18:41 upstream 614124bea77e b718257f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
* Struck through repros no longer work on HEAD.