syzbot


INFO: task hung in f2fs_issue_checkpoint

Status: upstream: reported on 2024/07/06 05:28
Reported-by: syzbot+ae3eae1f64c08f12e790@syzkaller.appspotmail.com
First crash: 103d, last: 94d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in f2fs_issue_checkpoint f2fs C error inconclusive 86 337d 717d 0/28 auto-obsoleted due to no activity on 2024/02/10 19:41
linux-5.15 INFO: task hung in f2fs_issue_checkpoint (2) 1 66d 66d 0/3 upstream: reported on 2024/08/12 23:40
linux-5.15 INFO: task hung in f2fs_issue_checkpoint 3 171d 198d 0/3 auto-obsoleted due to no activity on 2024/08/07 22:27

Sample crash report:
INFO: task syz.4.120:4080 blocked for more than 143 seconds.
      Not tainted 6.1.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.120       state:D stack:26040 pid:4080  ppid:3552   flags:0x00004004
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:2176 [inline]
 f2fs_issue_checkpoint+0x2d2/0x4d0 fs/f2fs/checkpoint.c:1864
 f2fs_create+0x862/0xa10 fs/f2fs/namei.c:377
 lookup_open fs/namei.c:3484 [inline]
 open_last_lookups fs/namei.c:3552 [inline]
 path_openat+0x12f1/0x2e60 fs/namei.c:3782
 do_filp_open+0x230/0x480 fs/namei.c:3812
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f319dd75bd9
RSP: 002b:00007f319eba2048 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f319df04110 RCX: 00007f319dd75bd9
RDX: 00000000000026e1 RSI: 00000000200000c0 RDI: ffffffffffffff9c
RBP: 00007f319dde4e60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f319df04110 R15: 00007ffc9f27b0e8
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u4:0/9:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12aed0 (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: ffffffff8d12b6d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
3 locks held by kworker/1:1/26:
 #0: ffff8880281fc538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90000a1fd20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4655
1 lock held by khungtaskd/28:
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d12ad00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
3 locks held by kworker/1:2/152:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90002dafd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:104
1 lock held by dhcpcd/3216:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x12e/0x6e0 net/netlink/af_netlink.c:2300
2 locks held by getty/3310:
 #0: ffff88814b19c098 (&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:2198
3 locks held by kworker/1:8/3656:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90004b07d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
2 locks held by kworker/u4:7/3706:
4 locks held by kworker/u4:14/3930:
 #0: ffff888143e56938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90005487d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffff88805a8a60e0 (&type->s_umount_key#51){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415
 #3: ffff888072dc9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline]
 #3: ffff888072dc9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428
5 locks held by syz.4.120/4034:
3 locks held by syz.4.120/4080:
 #0: ffff88805a8a6460 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff888070751bf0 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #1: ffff888070751bf0 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3549 [inline]
 #1: ffff888070751bf0 (&type->i_mutex_dir_key#8){+.+.}-{3:3}, at: path_openat+0x7b6/0x2e60 fs/namei.c:3782
 #2: ffff888072dc9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline]
 #2: ffff888072dc9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_issue_checkpoint+0x2d2/0x4d0 fs/f2fs/checkpoint.c:1864
5 locks held by syz.3.167/4181:
1 lock held by syz-executor/4249:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3489
1 lock held by syz-executor/4292:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor/4294:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz.1.205/4308:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3489
2 locks held by syz-executor/4311:
 #0: ffffffff8e28d8d0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x378/0x5d0 net/core/net_namespace.c:477
 #1: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x80/0x270 net/ipv4/nexthop.c:3605
1 lock held by syz-executor/4314:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor/4316:
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e299c28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.99-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
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:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4034 Comm: syz.4.120 Not tainted 6.1.99-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:variable_test_bit arch/x86/include/asm/bitops.h:228 [inline]
RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:240 [inline]
RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline]
RIP: 0010:mark_lock+0x9a/0x340 kernel/locking/lockdep.c:4606
Code: 28 84 c0 0f 85 29 02 00 00 8b 1b 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 20 c2 49 90 be 08 00 00 00 e8 c6 44 77 00 <48> 0f a3 1d 3e eb de 0e 73 11 48 8d 04 5b 48 c1 e0 06 48 8d 98 20
RSP: 0018:ffffc9000565e738 EFLAGS: 00000056
RAX: 0000000000000001 RBX: 0000000000000832 RCX: ffffffff816ad6da
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9049c320
RBP: 0000000000000003 R08: dffffc0000000000 R09: fffffbfff2093865
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88805b9fa898
R13: dffffc0000000000 R14: 0000000000000008 R15: ffff88805b9fa940
FS:  00007f319ebe46c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6012a66d95 CR3: 000000005ca57000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 mark_usage kernel/locking/lockdep.c:4529 [inline]
 __lock_acquire+0xbc3/0x1f80 kernel/locking/lockdep.c:5003
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 down_read+0xad/0xa30 kernel/locking/rwsem.c:1520
 check_valid_map fs/f2fs/gc.c:988 [inline]
 gc_data_segment fs/f2fs/gc.c:1540 [inline]
 do_garbage_collect+0x21ed/0x81f0 fs/f2fs/gc.c:1774
 f2fs_gc+0x1169/0x32a0 fs/f2fs/gc.c:1873
 f2fs_balance_fs+0x506/0x6c0 fs/f2fs/segment.c:429
 f2fs_map_blocks+0x2871/0x3ab0 fs/f2fs/data.c:1705
 expand_inode_data+0x56d/0xaf0 fs/f2fs/file.c:1749
 f2fs_fallocate+0x44a/0x9f0 fs/f2fs/file.c:1846
 vfs_fallocate+0x547/0x6b0 fs/open.c:323
 do_vfs_ioctl+0x222c/0x2a90 fs/ioctl.c:849
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl+0x81/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f319dd75bd9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f319ebe4048 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f319df03f60 RCX: 00007f319dd75bd9
RDX: 00000000200000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007f319dde4e60 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f319df03f60 R15: 00007ffc9f27b0e8
 </TASK>

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/15 08:52 linux-6.1.y cac15753b8ce c605e6a2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_issue_checkpoint
2024/07/10 08:22 linux-6.1.y 7753af06eebf bc144f9a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_issue_checkpoint
2024/07/07 10:24 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_issue_checkpoint
2024/07/06 05:43 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_issue_checkpoint
2024/07/06 05:27 linux-6.1.y 7753af06eebf 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in f2fs_issue_checkpoint
* Struck through repros no longer work on HEAD.