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KCSAN: data-race in __wait_discard_cmd_range / f2fs_submit_discard_endio

Status: auto-closed as invalid on 2021/05/04 19:40
Subsystems: f2fs
[Documentation on labels]
First crash: 1093d, last: 1093d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __wait_discard_cmd_range / f2fs_submit_discard_endio

write to 0xffff88804c4af842 of 1 bytes by interrupt on cpu 1:
 f2fs_submit_discard_endio+0xef/0x130 fs/f2fs/segment.c:1060
 bio_endio+0x2b0/0x370 block/bio.c:1451
 req_bio_endio block/blk-core.c:265 [inline]
 blk_update_request+0x4f5/0xb40 block/blk-core.c:1456
 blk_mq_end_request+0x22/0x50 block/blk-mq.c:564
 lo_complete_rq+0xca/0x180 drivers/block/loop.c:497
 blk_complete_reqs block/blk-mq.c:576 [inline]
 blk_done_softirq+0x69/0x90 block/blk-mq.c:581
 __do_softirq+0x13c/0x2c3 kernel/softirq.c:345
 run_ksoftirqd+0x13/0x20 kernel/softirq.c:652
 smpboot_thread_fn+0x34f/0x520 kernel/smpboot.c:165
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff88804c4af842 of 1 bytes by task 18801 on cpu 0:
 __wait_discard_cmd_range+0x182/0x3a0 fs/f2fs/segment.c:1627
 __wait_all_discard_cmd fs/f2fs/segment.c:1654 [inline]
 __issue_discard_cmd+0x1ec/0xea0 fs/f2fs/segment.c:1550
 f2fs_issue_discard_timeout+0x87/0x260 fs/f2fs/segment.c:1711
 f2fs_put_super+0x103/0x710 fs/f2fs/super.c:1369
 generic_shutdown_super+0xde/0x210 fs/super.c:464
 kill_block_super+0x4a/0x90 fs/super.c:1394
 kill_f2fs_super+0x164/0x190 fs/f2fs/super.c:4128
 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: 18801 Comm: syz-executor.3 Tainted: G        W         5.12.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/03/30 19:39 upstream 2bb25b3a748a 6a81331a .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __wait_discard_cmd_range / f2fs_submit_discard_endio
* Struck through repros no longer work on HEAD.