KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread

Status: auto-closed as invalid on 2021/05/05 01:36
Subsystems: btrfs
[Documentation on labels]
Reported-by: syzbot+65ecef0656795c48d0b3@syzkaller.appspotmail.com
First crash: 2154d, last: 1960d

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

write to 0xffff88802df540a4 of 4 bytes by task 3121 on cpu 1:
 caching_thread+0xe5/0x8d0 fs/btrfs/block-group.c:672
 btrfs_work_helper+0x1e2/0x380 fs/btrfs/async-thread.c:318
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff88802df540a4 of 4 bytes by task 8382 on cpu 0:
 btrfs_block_group_done fs/btrfs/block-group.h:314 [inline]
 btrfs_wait_block_group_cache_progress+0x149/0x2c0 fs/btrfs/block-group.c:406
 find_free_extent_clustered+0x5b7/0x740 fs/btrfs/extent-tree.c:3657
 do_allocation_clustered fs/btrfs/extent-tree.c:3743 [inline]
 do_allocation fs/btrfs/extent-tree.c:3870 [inline]
 find_free_extent+0xf08/0x22a0 fs/btrfs/extent-tree.c:4309
 btrfs_reserve_extent+0x135/0x2e0 fs/btrfs/extent-tree.c:4441
 btrfs_alloc_tree_block+0xfe/0x880 fs/btrfs/extent-tree.c:4840
 alloc_tree_block_no_bg_flush fs/btrfs/ctree.c:992 [inline]
 __btrfs_cow_block+0x2f2/0xac0 fs/btrfs/ctree.c:1048
 btrfs_cow_block+0x252/0x3a0 fs/btrfs/ctree.c:1495
 commit_cowonly_roots+0x94/0x590 fs/btrfs/transaction.c:1233
 btrfs_commit_transaction+0x99f/0x1980 fs/btrfs/transaction.c:2293
 btrfs_commit_super+0x8f/0xa0 fs/btrfs/disk-io.c:4210
 close_ctree+0x1c0/0x52d fs/btrfs/disk-io.c:4275
 btrfs_put_super+0x21/0x30 fs/btrfs/super.c:325
 generic_shutdown_super+0xde/0x210 fs/super.c:464
 kill_anon_super+0x23/0x40 fs/super.c:1056
 btrfs_kill_super+0x26/0x40 fs/btrfs/super.c:2353
 deactivate_locked_super+0x6a/0xb0 fs/super.c:335
 deactivate_super+0x85/0x90 fs/super.c:366
 cleanup_mnt+0x277/0x2e0 fs/namespace.c:1136
 __cleanup_mnt+0x15/0x20 fs/namespace.c:1143
 task_work_run+0x8e/0x110 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x17c/0x1b0 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8382 Comm: syz-executor.0 Not tainted 5.12.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (31):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/03/31 01:35 upstream 2bb25b3a748a 6a81331a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/03/15 21:47 upstream 1e28eed17697 fdb2bb2c .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/03/12 00:18 upstream 28806e4d9b97 429d8a6b .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/21 15:29 upstream e767b3530acb 3e5ed8b4 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/11 12:16 upstream 291009f656e8 a52ee10a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/10 10:06 upstream e0756cfc7d7c 9c8b8541 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/10 02:48 upstream e0756cfc7d7c 2bd9619f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/07 00:56 upstream 964d069f93c4 0655e081 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/02/02 05:32 upstream 88bb507a74ea e6b95f32 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/01/30 22:24 upstream 0e9bcda5d286 fc9fd31e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/01/29 11:42 upstream bec4c2968fce 6593fd32 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/01/27 22:39 upstream 76c057c84d28 a57db36f .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/01/23 21:05 upstream fe75a21824e7 52e37319 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in btrfs_wait_block_group_cache_progress / caching_thread
2021/01/16 08:56 upstream 1d94330a437a 65a7a854 .config console log report info ci2-upstream-kcsan-gce
2021/01/14 05:15 upstream 65f0d2414b70 269d24e8 .config console log report info ci2-upstream-kcsan-gce
2021/01/12 09:24 upstream a0d54b4f5b21 2c1f2513 .config console log report info ci2-upstream-kcsan-gce
2021/01/06 02:21 upstream 6207214a70bf b1c228e1 .config console log report info ci2-upstream-kcsan-gce
2020/12/31 16:30 upstream f6e1ea196492 79264ae3 .config console log report info ci2-upstream-kcsan-gce
2020/12/27 15:17 upstream f838f8d2b694 2242f77f .config console log report info ci2-upstream-kcsan-gce
2020/12/22 06:48 upstream 8653b778e454 04201c06 .config console log report info ci2-upstream-kcsan-gce
2020/12/19 23:37 upstream 467f8165a2b0 04201c06 .config console log report info ci2-upstream-kcsan-gce
2020/12/09 01:56 upstream 7d8761ba27fc 40cc414d .config console log report info ci2-upstream-kcsan-gce
2020/11/29 02:09 upstream 67f34fa8893e a0092f9d .config console log report info ci2-upstream-kcsan-gce
2020/11/23 14:53 upstream 418baf2c28f3 878fb17a .config console log report info ci2-upstream-kcsan-gce
2020/11/13 12:40 upstream 585e5b17b92d 4a7fa9b4 .config console log report info ci2-upstream-kcsan-gce
2020/10/25 22:15 upstream 986b9eacb259 a1839e81 .config console log report info ci2-upstream-kcsan-gce
2020/10/15 01:52 upstream 3e4fb4346c78 fc7735a2 .config console log report info ci2-upstream-kcsan-gce
2020/10/08 04:11 upstream c85fb28b6f99 1880b4a9 .config console log report info ci2-upstream-kcsan-gce
2020/09/27 08:00 upstream eeddbe6841cd 5dd8aee8 .config console log report info ci2-upstream-kcsan-gce
2020/09/18 08:55 upstream 10b82d517648 38962c8b .config console log report info ci2-upstream-kcsan-gce
2020/09/18 04:31 upstream 4cbffc461ec9 8247808b .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.