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KCSAN: data-race in iput / move_expired_inodes (6)

Status: auto-obsoleted due to no activity on 2023/02/22 21:07
Subsystems: fs
[Documentation on labels]
First crash: 492d, last: 492d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in iput / move_expired_inodes (5) fs 1 702d 702d 0/26 auto-closed as invalid on 2022/07/21 10:59
upstream KCSAN: data-race in iput / move_expired_inodes (8) fs 1 317d 317d 0/26 auto-obsoleted due to no activity on 2023/08/10 09:55
upstream KCSAN: data-race in iput / move_expired_inodes (10) fs 1 98d 98d 0/26 auto-obsoleted due to no activity on 2024/03/16 00:02
upstream KCSAN: data-race in iput / move_expired_inodes (7) fs 1 447d 447d 0/26 auto-obsoleted due to no activity on 2023/04/08 21:12
upstream KCSAN: data-race in iput / move_expired_inodes (9) fs 2 135d 157d 0/26 auto-obsoleted due to no activity on 2024/02/07 16:43
upstream KCSAN: data-race in iput / move_expired_inodes fs 5 1272d 1258d 0/26 auto-closed as invalid on 2020/12/27 22:09
upstream KCSAN: data-race in iput / move_expired_inodes (3) fs 3 1110d 1155d 0/26 auto-closed as invalid on 2021/06/07 20:37
upstream KCSAN: data-race in iput / move_expired_inodes (4) fs 1 981d 981d 0/26 auto-closed as invalid on 2021/10/15 01:41
upstream KCSAN: data-race in iput / move_expired_inodes (2) fs 1 1221d 1221d 0/26 auto-closed as invalid on 2021/02/16 20:27

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

read-write to 0xffff88810a922ce0 of 8 bytes by task 3151 on cpu 1:
 move_expired_inodes+0x1c0/0x4a0 fs/fs-writeback.c:1383
 queue_io+0xe1/0x2b0 fs/fs-writeback.c:1435
 wb_writeback+0x243/0x650 fs/fs-writeback.c:2061
 wb_check_start_all fs/fs-writeback.c:2187 [inline]
 wb_do_writeback+0x418/0x600 fs/fs-writeback.c:2213
 wb_workfn+0x88/0x260 fs/fs-writeback.c:2246
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

read to 0xffff88810a922ce0 of 8 bytes by task 3141 on cpu 0:
 iput+0x2e/0x580 fs/inode.c:1763
 dentry_unlink_inode+0x22a/0x240 fs/dcache.c:401
 __dentry_kill+0x28b/0x450 fs/dcache.c:607
 shrink_dentry_list+0x20f/0x380 fs/dcache.c:1201
 prune_dcache_sb+0x72/0xa0 fs/dcache.c:1282
 super_cache_scan+0x24e/0x300 fs/super.c:104
 do_shrink_slab+0x2ad/0x600 mm/vmscan.c:843
 shrink_slab_memcg+0x1c2/0x3e0 mm/vmscan.c:912
 shrink_slab+0x5c/0x1c0 mm/vmscan.c:991
 shrink_node_memcgs+0x277/0x450 mm/vmscan.c:6140
 shrink_node+0x1d7/0x930 mm/vmscan.c:6169
 shrink_zones+0x2c1/0x5d0 mm/vmscan.c:6407
 do_try_to_free_pages+0x195/0x760 mm/vmscan.c:6469
 try_to_free_mem_cgroup_pages+0x1d0/0x420 mm/vmscan.c:6786
 reclaim_high+0xd0/0x120 mm/memcontrol.c:2394
 mem_cgroup_handle_over_high+0x75/0x120 mm/memcontrol.c:2580
 resume_user_mode_work include/linux/resume_user_mode.h:58 [inline]
 exit_to_user_mode_loop+0xa5/0x130 kernel/entry/common.c:171
 exit_to_user_mode_prepare kernel/entry/common.c:203 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x6a/0x90 kernel/entry/common.c:296
 do_syscall_64+0x37/0x70 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000000007 -> 0x0000000000020087

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3141 Comm: syz-executor.3 Not tainted 6.2.0-rc3-syzkaller-00021-g7dd4b804e080-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/01/11 20:39 upstream 7dd4b804e080 96166539 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in iput / move_expired_inodes
* Struck through repros no longer work on HEAD.