syzbot


INFO: task hung in f2fs_balance_fs (2)

Status: auto-obsoleted due to no activity on 2024/03/06 18:04
Reported-by: syzbot+dfa2b7eab955fa4a19c0@syzkaller.appspotmail.com
First crash: 252d, last: 231d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in f2fs_balance_fs f2fs C 199 496d 636d 0/1 upstream: reported C repro on 2022/10/18 13:55
linux-6.1 INFO: task hung in f2fs_balance_fs (3) origin:lts-only C done 100 18h59m 110d 0/3 upstream: reported C repro on 2024/03/27 06:53
linux-4.14 INFO: task hung in f2fs_balance_fs 3 605d 632d 0/1 auto-obsoleted due to no activity on 2023/03/18 03:56
upstream INFO: task hung in f2fs_balance_fs f2fs C done inconclusive 561 10h42m 488d 0/27 upstream: reported C repro on 2023/03/15 03:28
linux-6.1 INFO: task hung in f2fs_balance_fs 20 432d 496d 0/3 auto-obsoleted due to no activity on 2023/08/22 15:19
linux-5.15 INFO: task hung in f2fs_balance_fs origin:upstream C 119 33m 495d 0/3 upstream: reported C repro on 2023/03/08 13:34

Sample crash report:
INFO: task kworker/u4:19:4234 blocked for more than 146 seconds.
      Not tainted 6.1.63-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:19   state:D stack:23640 pid:4234  ppid:2      flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:4)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 f2fs_down_write fs/f2fs/f2fs.h:2170 [inline]
 f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:426
 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:749
 write_inode fs/fs-writeback.c:1460 [inline]
 __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677
 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903
 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974
 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079
 wb_check_old_data_flush fs/fs-writeback.c:2179 [inline]
 wb_do_writeback fs/fs-writeback.c:2232 [inline]
 wb_workfn+0xbec/0x1020 fs/fs-writeback.c:2260
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12a2b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12aab0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
 #0: ffffffff8d12a0e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]
 #0: ffffffff8d12a0e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8d12a0e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6493
2 locks held by getty/3301:
 #0: ffff88814b275098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
3 locks held by kworker/u4:6/3698:
 #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90004517d20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8d12f580 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:3965
4 locks held by kworker/u4:19/4234:
 #0: ffff888015286938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000b63fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffff88801871a0e0 (&type->s_umount_key#54){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415
 #3: ffff88807eb35140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2170 [inline]
 #3: ffff88807eb35140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:426
3 locks held by kworker/u4:23/7959:
 #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90003affd20 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8d12f580 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x48/0x5f0 kernel/rcu/tree.c:3965
3 locks held by syz-executor.4/20380:
1 lock held by syz-executor.4/23437:
 #0: ffff888017f7db58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
 #0: ffff888017f7db58 (&mm->mmap_lock){++++}-{3:3}, at: vm_mmap_pgoff+0x175/0x2d0 mm/util.c:518

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

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.63-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 3628 Comm: kworker/1:6 Not tainted 6.1.63-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:page_expected_state mm/page_alloc.c:1238 [inline]
RIP: 0010:check_new_page mm/page_alloc.c:2369 [inline]
RIP: 0010:check_new_pages+0x189/0x370 mm/page_alloc.c:2383
Code: 84 b2 fe ff ff 4a 8d 6c 3b 70 48 89 ef be 04 00 00 00 e8 6a e9 0a 00 48 89 e8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 2f 8b 45 00 <49> 83 c7 40 83 f8 ff 0f 84 09 ff ff ff eb 3f 89 e9 80 e1 07 80 c1
RSP: 0018:ffffc9000436f368 EFLAGS: 00000246
RAX: 00000000ffffffff RBX: ffffea0001157800 RCX: ffffffff81d6ff36
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffea00011578f0
RBP: ffffea00011578f0 R08: dffffc0000000000 R09: fffff9400022af1f
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000003
R13: 0000000000000001 R14: dffffc0000000000 R15: 0000000000000080
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda09d78038 CR3: 000000000ce8e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 check_new_pcp mm/page_alloc.c:2406 [inline]
 __rmqueue_pcplist+0x21ca/0x2310 mm/page_alloc.c:3761
 rmqueue_pcplist mm/page_alloc.c:3791 [inline]
 rmqueue mm/page_alloc.c:3834 [inline]
 get_page_from_freelist+0x86c/0x3320 mm/page_alloc.c:4276
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node_track_caller+0xa0/0x220 mm/slab_common.c:975
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x135/0x670 net/core/skbuff.c:515
 alloc_skb include/linux/skbuff.h:1276 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x24c/0xa90 drivers/net/netdevsim/dev.c:850
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/11/27 18:03 linux-6.1.y 69e434a1cb21 7ec6c044 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_balance_fs
2023/11/06 05:24 linux-6.1.y 4a61839152cc 500bfdc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_balance_fs
* Struck through repros no longer work on HEAD.