INFO: task kworker/u8:4:62 blocked for more than 143 seconds.
Not tainted 6.15.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:4 state:D stack:23448 pid:62 tgid:62 ppid:2 task_flags:0x4248060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
io_schedule+0xbf/0x130 kernel/sched/core.c:7742
bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247
__wait_on_bit_lock+0x112/0x1a0 kernel/sched/wait_bit.c:90
out_of_line_wait_on_bit_lock+0xd9/0x110 kernel/sched/wait_bit.c:117
wait_on_bit_lock_io include/linux/wait_bit.h:221 [inline]
__lock_buffer+0x67/0x70 fs/buffer.c:71
lock_buffer include/linux/buffer_head.h:434 [inline]
do_get_write_access+0x8cd/0x12a0 fs/jbd2/transaction.c:968
jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1241
__ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
ext4_mb_mark_context+0x175/0xd40 fs/ext4/mballoc.c:4001
ext4_mb_mark_diskspace_used+0x466/0x8c0 fs/ext4/mballoc.c:4131
ext4_mb_new_blocks+0xa5b/0x4f00 fs/ext4/mballoc.c:6233
ext4_ext_map_blocks+0x1b95/0x5d60 fs/ext4/extents.c:4379
ext4_map_create_blocks fs/ext4/inode.c:520 [inline]
ext4_map_blocks+0x45b/0x1390 fs/ext4/inode.c:706
mpage_map_one_extent fs/ext4/inode.c:2224 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2277 [inline]
ext4_do_writepages+0x1a2c/0x3490 fs/ext4/inode.c:2739
ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:2829
do_writepages+0x1b2/0x820 mm/page-writeback.c:2656
__writeback_single_inode+0x160/0xfb0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x601/0xf90 fs/fs-writeback.c:1976
__writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2047
wb_writeback+0x7f3/0xb70 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0x8ca/0xbe0 fs/fs-writeback.c:2343
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task jbd2/sda1-8:5162 blocked for more than 144 seconds.
Not tainted 6.15.0-rc4-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8 state:D stack:25224 pid:5162 tgid:5162 ppid:2 task_flags:0x240040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x116f/0x5de0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6860
io_schedule+0xbf/0x130 kernel/sched/core.c:7742
bit_wait_io+0x15/0xe0 kernel/sched/wait_bit.c:247
__wait_on_bit+0x62/0x180 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0xd9/0x110 kernel/sched/wait_bit.c:64
wait_on_bit_io include/linux/wait_bit.h:105 [inline]
__wait_on_buffer+0x64/0x70 fs/buffer.c:123
wait_on_buffer include/linux/buffer_head.h:422 [inline]
jbd2_journal_commit_transaction+0x382e/0x6830 fs/jbd2/commit.c:808
kjournald2+0x1f4/0x760 fs/jbd2/journal.c:201
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e3bf440 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764
6 locks held by kworker/u8:4/62:
#0: ffff888021a8c148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc9000154fd18 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffff88814e09a0e0 (&type->s_umount_key#31){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:562
#3: ffff88814e09cb98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x1b2/0x820 mm/page-writeback.c:2656
#4: ffff88814e09e950 (jbd2_handle){.+.+}-{0:0}, at: start_this_handle+0x5e4/0x1410 fs/jbd2/transaction.c:444
#5: ffff88807d3565d8 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x355/0x1390 fs/ext4/inode.c:705
2 locks held by getty/5587:
#0: ffff888035d6a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by syz-executor155/12311:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Call Trace:
__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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:81
Code: 86 65 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 03 29 21 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c2
RAX: 000000000015eb27 RBX: 0000000000000001 RCX: ffffffff8b68c3e9
RDX: 0000000000000000 RSI: ffffffff8dbd98cb RDI: ffffffff8bf46720
RBP: ffffed1003b5eb40 R08: 0000000000000001 R09: ffffed10170a65bd
R10: ffff8880b8532deb R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801daf5a00 R14: ffffffff90850e10 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124aef000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa59b8b80f0 CR3: 000000000e180000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:748
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148