syzbot


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

Status: moderation: reported on 2021/06/26 18:58
Subsystems: fs mm
[Documentation on labels]
Reported-by: syzbot+03743c59b799c7b55cd4@syzkaller.appspotmail.com
First crash: 1639d, last: 11h26m
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 mm fs 6 558 1640d 1941d 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 0xffff88811a618b50 of 8 bytes by interrupt on cpu 0:
 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:2100
 __folio_end_writeback+0xf7/0x3b0 mm/page-writeback.c:2992
 folio_end_writeback_no_dropbehind+0x6d/0x1b0 mm/filemap.c:1655
 folio_end_writeback+0x1c/0x70 mm/filemap.c:1681
 mpage_write_end_io+0x274/0x390 fs/mpage.c:65
 bio_endio+0x37e/0x420 block/bio.c:1672
 blk_update_request+0x336/0x730 block/blk-mq.c:998
 blk_mq_end_request+0x26/0x50 block/blk-mq.c:1160
 lo_complete_rq+0x98/0x140 drivers/block/loop.c:314
 blk_complete_reqs block/blk-mq.c:1235 [inline]
 blk_done_softirq+0x77/0xb0 block/blk-mq.c:1240
 handle_softirqs+0xba/0x290 kernel/softirq.c:622
 run_ksoftirqd+0x1c/0x30 kernel/softirq.c:1063
 smpboot_thread_fn+0x32b/0x530 kernel/smpboot.c:160
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read to 0xffff88811a618b50 of 8 bytes by task 6365 on cpu 1:
 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:2057
 filemap_get_folios_tag+0x13b/0x210 mm/filemap.c:2325
 __filemap_fdatawait_range mm/filemap.c:522 [inline]
 file_write_and_wait_range+0x1ea/0x2c0 mm/filemap.c:788
 __generic_file_fsync+0x46/0x160 fs/libfs.c:1540
 fat_file_fsync+0x49/0x100 fs/fat/file.c:191
 vfs_fsync_range+0x10d/0x130 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2617 [inline]
 generic_file_write_iter+0x1b8/0x2f0 mm/filemap.c:4447
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x52a/0x960 fs/read_write.c:686
 ksys_pwrite64 fs/read_write.c:793 [inline]
 __do_sys_pwrite64 fs/read_write.c:801 [inline]
 __se_sys_pwrite64 fs/read_write.c:798 [inline]
 __x64_sys_pwrite64+0xfd/0x150 fs/read_write.c:798
 x64_sys_call+0x9f7/0x3000 arch/x86/include/generated/asm/syscalls_64.h:19
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd8/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000000000001fffe -> 0x000000000001ff00

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6365 Comm: syz.2.16376 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
==================================================================

Crashes (4968):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/03 01:39 upstream d61f1cc5db79 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/12/02 13:03 upstream 4a26e7032d7d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/12/01 23:06 upstream 1d18101a644e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/12/01 07:45 upstream 7d0a66e4bb90 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/30 17:42 upstream e69c7c175115 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/30 00:46 upstream 6bda50f4333f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/28 14:40 upstream e538109ac71d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/28 00:58 upstream e1afacb68573 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/26 21:59 upstream 4941a17751c9 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/26 13:43 upstream 30f09200cc4a d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/26 06:09 upstream 30f09200cc4a 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/25 18:35 upstream 8a2bcda5e139 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/25 01:16 upstream ac3fd01e4c1e 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/24 12:18 upstream ac3fd01e4c1e bf6fe8fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/23 23:58 upstream d0e88704d96c 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/23 09:00 upstream d13f3ac64efb 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/22 19:53 upstream 89edd36fd801 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/21 21:20 upstream 2eba5e05d9bc 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/21 19:09 upstream fd95357fd8c6 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/21 08:27 upstream fd95357fd8c6 280ea308 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/19 20:46 upstream 23cb64fb7625 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/19 10:47 upstream 8b690556d8fe 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/19 07:23 upstream 8b690556d8fe ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/18 18:11 upstream 5bebe8de1926 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/17 19:44 upstream e7c375b18160 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/17 12:18 upstream 6a23ae0a96a6 ef766cd7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/17 05:32 upstream 6a23ae0a96a6 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/16 16:29 upstream 7254a2b52279 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/15 22:01 upstream f824272b6e3f f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/15 08:34 upstream 7a0892d2836e f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/14 20:02 upstream d4f8cccc6230 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/14 12:41 upstream 6da43bbeb691 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/14 06:35 upstream 6da43bbeb691 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/13 17:12 upstream 2ccec5944606 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/13 03:01 upstream e927c520e1ba 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/12 13:19 upstream 24172e0d7990 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/11 21:58 upstream 24172e0d7990 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/11 08:02 upstream 4427259cc7f7 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/10 19:07 upstream 4ea7c1717f3f 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/10 02:45 upstream e9a6fb0bcdd7 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/09 13:27 upstream 439fc29dfd3b 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/08 10:30 upstream e811c33b1f13 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/07 21:20 upstream da32d155f4a8 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/07 08:19 upstream 4a0c9b339199 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/06 19:06 upstream c2c2ccfd4ba7 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/06 17:06 upstream dc77806cf3b4 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/06 09:34 upstream dc77806cf3b4 a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __xa_clear_mark / xas_find_marked
2025/11/05 20:27 upstream 1c353dc8d962 a6c9c731 .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.