syzbot


INFO: task hung in jbd2_complete_transaction (3)

Status: auto-obsoleted due to no activity on 2025/02/18 06:44
Subsystems: ext4
[Documentation on labels]
First crash: 281d, last: 281d
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in jbd2_complete_transaction ext4 1 1 2625d 2624d 0/29 auto-closed as invalid on 2019/02/22 10:22
upstream INFO: task hung in jbd2_complete_transaction (2) ext4 1 1 463d 463d 0/29 auto-obsoleted due to no activity on 2024/08/19 14:59
upstream INFO: task hung in jbd2_complete_transaction (4) ext4 1 1 130d 130d 0/29 auto-obsoleted due to no activity on 2025/07/18 21:27

Sample crash report:
INFO: task syz.9.1702:13439 blocked for more than 143 seconds.
      Not tainted 6.12.0-syzkaller-01782-gbf9aa14fc523 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1702      state:D stack:24976 pid:13439 tgid:13437 ppid:13229  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0xe5a/0x5ae0 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6848
 jbd2_log_wait_commit+0x2ef/0x460 fs/jbd2/journal.c:673
 jbd2_complete_transaction+0x18f/0x200 fs/jbd2/journal.c:799
 ext4_fc_commit+0x6cd/0xa40 fs/ext4/fast_commit.c:1213
 ext4_fsync_journal fs/ext4/fsync.c:115 [inline]
 ext4_sync_file+0x44f/0xf30 fs/ext4/fsync.c:167
 vfs_fsync_range+0x136/0x220 fs/sync.c:187
 __do_sys_msync+0x3c6/0x5b0 mm/msync.c:96
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa8da77e759
RSP: 002b:00007fa8db57c038 EFLAGS: 00000246 ORIG_RAX: 000000000000001a
RAX: ffffffffffffffda RBX: 00007fa8da936058 RCX: 00007fa8da77e759
RDX: 0000000400000004 RSI: 0080100000000005 RDI: 000000001ffff000
RBP: 00007fa8da7f175e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa8da936058 R15: 00007ffcfe230978
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/u8:0/11:
 #0: ffff8881416dc948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204
 #1: ffffc90000107d80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205
 #2: ffff8880356120e0 (&type->s_umount_key#32){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:562
 #3: ffff888035614b98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x1b3/0x820 mm/page-writeback.c:2683
 #4: ffff888035616958 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xf6c/0x1430 fs/jbd2/transaction.c:448
 #5: ffff88807846a040 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x352/0x1370 fs/ext4/inode.c:701
1 lock held by khungtaskd/30:
 #0: ffffffff8ddba640 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8ddba640 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8ddba640 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744
1 lock held by klogd/5209:
2 locks held by getty/5601:
 #0: ffff888030f2b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/5856:
 #0: ffff888034107658 (&vma->vm_lock->lock){++++}-{4:4}, at: vma_start_read include/linux/mm.h:716 [inline]
 #0: ffff888034107658 (&vma->vm_lock->lock){++++}-{4:4}, at: lock_vma_under_rcu+0x13e/0x980 mm/memory.c:6243
 #1: ffff888035612518 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x177/0x380 mm/memory.c:3162
 #2: ffff88807846a350 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:873 [inline]
 #2: ffff88807846a350 (mapping.invalidate_lock){++++}-{4:4}, at: ext4_page_mkwrite+0x37e/0x1760 fs/ext4/inode.c:6161
 #3: ffff88807846a040 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_map_blocks fs/ext4/inode.c:1809 [inline]
 #3: ffff88807846a040 (&ei->i_data_sem){++++}-{4:4}, at: ext4_da_get_block_prep+0x6a0/0x11e0 fs/ext4/inode.c:1873
2 locks held by kworker/u8:8/6159:
2 locks held by syz.1.1760/14101:
 #0: ffff88807611c420 (sb_writers#5){.+.+}-{0:0}, at: get_signal+0x23f3/0x2610 kernel/signal.c:3001
 #1: ffff8880524fd9a0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline]
 #1: ffff8880524fd9a0 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1726 [inline]
 #1: ffff8880524fd9a0 (&mm->mmap_lock){++++}-{4:4}, at: get_dump_page+0xb6/0x220 mm/gup.c:2269
2 locks held by syz.2.1769/14116:
 #0: ffff8880294de420 (sb_writers#5){.+.+}-{0:0}, at: get_signal+0x23f3/0x2610 kernel/signal.c:3001
 #1: ffff888061fca8e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline]
 #1: ffff888061fca8e0 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1726 [inline]
 #1: ffff888061fca8e0 (&mm->mmap_lock){++++}-{4:4}, at: get_dump_page+0xb6/0x220 mm/gup.c:2269
2 locks held by syz.4.1767/14128:
 #0: ffff888033546420 (sb_writers#5){.+.+}-{0:0}, at: get_signal+0x23f3/0x2610 kernel/signal.c:3001
 #1: ffff88807aa9cfe0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline]
 #1: ffff88807aa9cfe0 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1726 [inline]
 #1: ffff88807aa9cfe0 (&mm->mmap_lock){++++}-{4:4}, at: get_dump_page+0xb6/0x220 mm/gup.c:2269
2 locks held by syz.1.1774/14168:
 #0: ffff88807611c420 (sb_writers#5){.+.+}-{0:0}, at: get_signal+0x23f3/0x2610 kernel/signal.c:3001
 #1: ffff8880356f4fe0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline]
 #1: ffff8880356f4fe0 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1726 [inline]
 #1: ffff8880356f4fe0 (&mm->mmap_lock){++++}-{4:4}, at: get_dump_page+0xb6/0x220 mm/gup.c:2269
2 locks held by syz.1.1774/14172:
 #0: ffff88807611c420 (sb_writers#5){.+.+}-{0:0}, at: get_signal+0x23f3/0x2610 kernel/signal.c:3001
 #1: ffff88801ac74fe0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:153 [inline]
 #1: ffff88801ac74fe0 (&mm->mmap_lock){++++}-{4:4}, at: __get_user_pages_locked mm/gup.c:1726 [inline]
 #1: ffff88801ac74fe0 (&mm->mmap_lock){++++}-{4:4}, at: get_dump_page+0xb6/0x220 mm/gup.c:2269

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-syzkaller-01782-gbf9aa14fc523 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xf0c/0x1240 kernel/hung_task.c:379
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 68 Comm: kworker/u8:4 Not tainted 6.12.0-syzkaller-01782-gbf9aa14fc523 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:kasan_save_stack+0x28/0x60 mm/kasan/common.c:44
Code: 90 90 66 0f 1f 00 41 54 31 c0 b9 40 00 00 00 41 89 f4 55 89 fd 31 d2 be 40 00 00 00 53 48 81 ec 00 02 00 00 48 89 e3 48 89 df <f3> 48 ab 48 89 df e8 ed 62 8a ff 44 89 e1 89 ea 48 89 df 89 c6 e8
RSP: 0018:ffffc900015d7868 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffffc900015d7868 RCX: 0000000000000010
RDX: 0000000000000000 RSI: 0000000000000040 RDI: ffffc900015d79e8
RBP: 0000000000082820 R08: 0000000000000007 R09: 0000000000000000
R10: ffff88803346d000 R11: 000000000000004f R12: 0000000000000001
R13: 0000000000001000 R14: 0000000000001000 R15: 00000000ffffffff
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564cd36fa600 CR3: 000000000db7e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:257 [inline]
 __do_kmalloc_node mm/slub.c:4264 [inline]
 __kmalloc_node_track_caller_noprof+0x20f/0x440 mm/slub.c:4283
 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:609
 __alloc_skb+0x164/0x380 net/core/skbuff.c:678
 alloc_skb include/linux/skbuff.h:1322 [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+0x2a4/0xc90 drivers/net/netdevsim/dev.c:851
 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/11/20 06:35 upstream bf9aa14fc523 7d02db5a .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto INFO: task hung in jbd2_complete_transaction
* Struck through repros no longer work on HEAD.