syzbot


INFO: task hung in evict

Status: upstream: reported C repro on 2025/01/27 17:28
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+c6778d0597c63956b321@syzkaller.appspotmail.com
First crash: 399d, last: 12h52m
Fix commit to backport (bisect log) :
tree: upstream
commit 5641371fd0b3703d11809a0ae249aed270cb8add
Author: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Fri Dec 20 22:46:27 2024 +0000

  squashfs; convert squashfs_copy_cache() to take a folio

  
Fix bisection: the issue occurs on the latest tested release (bisect log)
Crash: INFO: task hung in evict (log)
Repro: C syz .config
  
Bug presence (2)
Date Name Commit Repro Result
2025/03/19 linux-5.15.y (ToT) 0c935c049b5c C [report] INFO: task hung in evict
2025/03/19 upstream (ToT) 81e4f8d68c66 C Didn't crash
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: task hung in evict origin:upstream 1 C 247 7d06h 238d 0/2 upstream: reported C repro on 2025/07/07 18:12
upstream INFO: task hung in evict (2) squashfs 1 C done 2513 8h31m 747d 0/29 upstream: reported C repro on 2024/02/14 14:00
linux-6.1 INFO: task hung in evict origin:lts-only 1 C inconclusive 1544 8h16m 399d 0/3 upstream: reported C repro on 2025/01/27 18:40
upstream INFO: task hung in evict ext4 1 1 1347d 1347d 0/29 auto-closed as invalid on 2022/09/22 02:36
Last patch testing requests (6)
Created Duration User Patch Repo Result
2025/10/17 03:25 17m retest repro linux-5.15.y report log
2025/10/17 03:25 12m retest repro linux-5.15.y report log
2025/09/16 15:49 16m retest repro linux-5.15.y report log
2025/08/07 17:51 18m retest repro linux-5.15.y report log
2025/08/07 17:51 20m retest repro linux-5.15.y report log
2025/07/04 01:52 29m retest repro linux-5.15.y report log
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/05/18 17:57 6h32m fix candidate upstream OK (1) job log
2025/04/24 08:43 1h56m bisect fix linux-5.15.y OK (0) job log log

Sample crash report:
INFO: task syz-executor:4289 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21808 pid: 4289 ppid:     1 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356
 lock_page include/linux/pagemap.h:625 [inline]
 truncate_inode_pages_range+0xa24/0xfe0 mm/truncate.c:394
 evict+0x4dc/0x8d0 fs/inode.c:649
 dispose_list fs/inode.c:680 [inline]
 evict_inodes+0x60c/0x6a0 fs/inode.c:734
 generic_shutdown_super+0x93/0x300 fs/super.c:454
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f25b7fd1117
RSP: 002b:00007ffd233bfb58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f25b803971f RCX: 00007f25b7fd1117
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd233bfc10
RBP: 00007ffd233bfc10 R08: 00007ffd233c0c10 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd233c0ca0
R13: 00007f25b803971f R14: 00000000000113f1 R15: 00007ffd233c0ce0
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:3/155:
 #0: ffff8880b913a358 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffffc90001f27d00 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by getty/3949:
 #0: ffff88814d163098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cf62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
1 lock held by syz-executor/4289:
 #0: ffff8880278c20e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4320:
 #0: ffff8880789e40e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4352:
 #0: ffff888019b9c0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4374:
 #0: ffff88807a7120e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4395:
 #0: ffff88802a5560e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4429:
 #0: ffff888057ff40e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4456:
 #0: ffff88805b9940e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
1 lock held by syz-executor/4483:
 #0: ffff8880581b80e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4711 [inline]
RIP: 0010:__lock_acquire+0x92d/0x7d10 kernel/locking/lockdep.c:4962
Code: 89 c6 41 81 e6 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 c0 20 1d 90 be 08 00 00 00 e8 bb 1e 61 00 4c 0f a3 35 53 11 c0 0e <73> 1a 4b 8d 04 76 c1 e0 06 4c 8d b0 80 9f b5 8f 49 b8 00 00 00 00
RSP: 0018:ffffc90000ce6f20 EFLAGS: 00000057
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff815d0f65
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff901d20f8
RBP: ffffc90000ce7170 R08: ffffffff901d20ff R09: 1ffffffff203a41f
R10: dffffc0000000000 R11: fffffbfff203a420 R12: ffff88813fe90b10
R13: ffff88813fe90b04 R14: 00000000000001da R15: ffff88813fe90b10
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055cb5cfe2168 CR3: 000000002b18f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
 krc_this_cpu_lock kernel/rcu/tree.c:3203 [inline]
 add_ptr_to_bulk_krc_lock kernel/rcu/tree.c:3510 [inline]
 kvfree_call_rcu+0x18d/0x7d0 kernel/rcu/tree.c:3601
 cfg80211_update_known_bss+0x178/0xa20 net/wireless/scan.c:-1
 cfg80211_bss_update+0x15f/0x2250 net/wireless/scan.c:1836
 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2555 [inline]
 cfg80211_inform_bss_frame_data+0x89f/0x1fc0 net/wireless/scan.c:2588
 ieee80211_bss_info_update+0x6be/0xa70 net/mac80211/scan.c:190
 ieee80211_rx_bss_info net/mac80211/ibss.c:1123 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1614 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1700/0x2ab0 net/mac80211/ibss.c:1643
 ieee80211_iface_process_skb net/mac80211/iface.c:1459 [inline]
 ieee80211_iface_work+0x70e/0xc60 net/mac80211/iface.c:1513
 cfg80211_wiphy_work+0x221/0x260 net/wireless/core.c:433
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (376):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/02/08 21:43 linux-5.15.y 7b232985052f 4c131dc4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2025/12/17 09:05 linux-5.15.y 68efe5a6c16a d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2025/10/30 09:05 linux-5.15.y cc5ec8769306 fd2207e7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2025/07/17 10:54 linux-5.15.y 89950c454265 44f8051e .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2025/07/07 14:07 linux-5.15.y 3dea0e7f549e 4f67c4ae .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2025/02/02 18:04 linux-5.15.y c16c81c81336 568559e4 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan INFO: task hung in evict
2026/03/02 09:16 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/03/02 05:58 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/03/02 03:14 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/03/02 02:11 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/03/01 04:31 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/28 20:36 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/28 03:46 linux-5.15.y 3330a8d33e08 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/27 18:16 linux-5.15.y 3330a8d33e08 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/27 15:42 linux-5.15.y 3330a8d33e08 2cf092b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/27 00:31 linux-5.15.y 3330a8d33e08 a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/27 00:31 linux-5.15.y 3330a8d33e08 a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/26 11:53 linux-5.15.y 3330a8d33e08 ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/25 23:43 linux-5.15.y 3330a8d33e08 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/25 14:12 linux-5.15.y 3330a8d33e08 94a9671e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/25 11:26 linux-5.15.y 3330a8d33e08 94a9671e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 13:51 linux-5.15.y 3330a8d33e08 6beca497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 11:19 linux-5.15.y 3330a8d33e08 6beca497 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 08:57 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 06:33 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 01:09 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/23 00:20 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/22 07:24 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/22 00:55 linux-5.15.y 3330a8d33e08 6e7b5511 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/20 09:35 linux-5.15.y 3330a8d33e08 17d780d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/19 21:05 linux-5.15.y 3330a8d33e08 c8d8c52d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/19 18:55 linux-5.15.y 3330a8d33e08 c8d8c52d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/19 16:50 linux-5.15.y 3330a8d33e08 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/19 06:26 linux-5.15.y e45d5d41c134 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/19 04:37 linux-5.15.y e45d5d41c134 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/18 18:33 linux-5.15.y e45d5d41c134 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/17 16:05 linux-5.15.y e45d5d41c134 06ec4f7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/17 03:47 linux-5.15.y e45d5d41c134 e439b951 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/16 17:31 linux-5.15.y e45d5d41c134 5d52cba5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/16 07:20 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/15 20:06 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/15 18:43 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/15 17:41 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/14 18:56 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/14 17:49 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/14 13:01 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/13 17:45 linux-5.15.y e45d5d41c134 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/11 15:40 linux-5.15.y e45d5d41c134 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/11 12:31 linux-5.15.y 7b232985052f 75707236 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/11 05:19 linux-5.15.y 7b232985052f 441e25b7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/10 01:49 linux-5.15.y 7b232985052f 4ab09a02 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/09 11:46 linux-5.15.y 7b232985052f df949cd9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2026/02/07 00:49 linux-5.15.y 7b232985052f f20fc9f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
2025/01/27 17:27 linux-5.15.y 003148680b79 d99a33ad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in evict
* Struck through repros no longer work on HEAD.