INFO: task syz.0.1235:11127 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1235 state:D stack:27920 pid:11127 tgid:11118 ppid:5595 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x1259/0x6920 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7376
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7433
__mutex_lock_common kernel/locking/mutex.c:726 [inline]
__mutex_lock+0xccb/0x1bd0 kernel/locking/mutex.c:821
bdev_open+0xa2/0xe40 block/bdev.c:990
bdev_file_open_by_dev block/bdev.c:1104 [inline]
bdev_file_open_by_dev+0x179/0x210 block/bdev.c:1079
fs_bdev_file_open_by_dev fs/super.c:1699 [inline]
setup_bdev_super+0x78/0x770 fs/super.c:1791
get_tree_bdev_flags+0x363/0x620 fs/super.c:1870
vfs_get_tree+0x92/0x320 fs/super.c:1932
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3772 [inline]
do_new_mount fs/namespace.c:3848 [inline]
path_mount+0x7d0/0x24c0 fs/namespace.c:4168
do_mount fs/namespace.c:4181 [inline]
__do_sys_mount fs/namespace.c:4397 [inline]
__se_sys_mount fs/namespace.c:4374 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4374
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6bb1d9e159
RSP: 002b:00007f6baf7d1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6bb2026360 RCX: 00007f6bb1d9e159
RDX: 0000200000000040 RSI: 0000200000000000 RDI: 0000200000000080
RBP: 00007f6bb1e3506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000204000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6bb20263f8 R14: 00007f6bb2026360 R15: 00007ffe819df018
Showing all locks held in the system:
locks held by khungtaskd/31: 1, last CPU#1:
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6871
locks held by udevd/10554: 1, on CPU#1:
#0: ffff888028366350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:990
locks held by syz-executor/10557: 4, last CPU#1:
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: dup_mm kernel/fork.c:1542 [inline]
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: copy_mm kernel/fork.c:1595 [inline]
#0: ffffffff8ef3deb0 (dup_mmap_sem){++++}-{0:0}, at: copy_process+0x4816/0x8380 kernel/fork.c:2311
#1: ffff88807d44b440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline]
#1: ffff88807d44b440 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x127/0x2370 mm/mmap.c:1716
#2: ffff88807c548340 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:552 [inline]
#2: ffff88807c548340 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x1c9/0x2370 mm/mmap.c:1723
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by syz.0.1235/11127: 2, on CPU#0:
#0: ffff8880503280e8 (&type->s_umount_key#91/1){+.+.}-{4:4}, at: alloc_super fs/super.c:351 [inline]
#0: ffff8880503280e8 (&type->s_umount_key#91/1){+.+.}-{4:4}, at: sget_fc+0x3c6/0x1f70 fs/super.c:874
#1: ffff888028366350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xa2/0xe40 block/bdev.c:990
locks held by syz-executor/11253: 2, last CPU#1:
#0: ffff888037f5a460 (sb_writers#6){.+.+}-{0:0}, at: filename_unlinkat+0x1ad/0x730 fs/namei.c:5696
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire.constprop.0+0x7/0x30 include/linux/rcupdate.h:309
locks held by getty/12165: 2, on CPU#1:
#0: ffff88802baae0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900071112e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
locks held by syz.3.1549/12375: 2, last CPU#1:
#0: ffff888058a55900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff888058a55900 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x124/0xa00 mm/mmap.c:1299
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8edec5a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x2f/0x310 mm/pgtable-generic.c:290
locks held by syz.2.1550/12378: 2, last CPU#0:
#0: ffff888033b36460 (sb_writers#6){.+.+}-{0:0}, at: get_signal+0x1f2a/0x21e0 kernel/signal.c:3097
#1: ffff88807d30c080 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:609 [inline]
#1: ffff88807d30c080 (&mm->mmap_lock){++++}-{4:4}, at: dump_user_range+0x151/0xad0 fs/coredump.c:1349
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x21f/0x2a0 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x141/0x190 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xcb1/0x1030 kernel/hung_task.c:561
kthread+0x373/0x450 kernel/kthread.c:436
ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12378 Comm: syz.2.1550 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4435 [inline]
RIP: 0010:lockdep_hardirqs_on_prepare+0x52/0x1c0 kernel/locking/lockdep.c:4406
Code: 8b 05 1a 03 a6 12 85 c0 0f 85 e5 00 00 00 65 8b 05 67 fe a5 12 85 c0 0f 85 d6 00 00 00 44 8b 0d e4 31 b3 19 53 45 85 c9 75 31 <9c> 58 f6 c4 02 0f 85 de 00 00 00 8b 3d cd 31 b3 19 85 ff 75 1c 80
RSP: 0000:ffffc9000d816a60 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffff88804c4c9b88 RCX: ffffffff82149e7f
RDX: 0000000000000000 RSI: ffffffff8c623900 RDI: ffffffff8e65a920
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000001801
R13: ffffc9000d816af0 R14: 0000000000000000 R15: 0000000000000000
FS: 00007fca7805f6c0(0000) GS:ffff888123b4f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffffffffffffe70 CR3: 0000000078b73000 CR4: 00000000003526f0
Call Trace:
trace_hardirqs_on+0x36/0x40 kernel/trace/trace_preemptirq.c:78
__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:219 [inline]
_raw_spin_unlock_irq+0x23/0x50 kernel/locking/spinlock.c:229
spin_unlock_irq include/linux/spinlock.h:413 [inline]
shmem_add_to_page_cache+0x874/0xcd0 mm/shmem.c:939
shmem_alloc_and_add_folio+0x558/0xd40 mm/shmem.c:2004
shmem_get_folio_gfp+0x75b/0x1980 mm/shmem.c:2531
shmem_get_folio mm/shmem.c:2637 [inline]
shmem_write_begin+0x1a4/0x420 mm/shmem.c:3268
generic_perform_write+0x292/0xa40 mm/filemap.c:4374
shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3443
__kernel_write_iter+0x2ac/0x930 fs/read_write.c:621
dump_emit_page fs/coredump.c:1293 [inline]
dump_user_range+0x3f9/0xad0 fs/coredump.c:1367
elf_core_dump+0x2d68/0x3d20 fs/binfmt_elf.c:2106
coredump_write fs/coredump.c:1047 [inline]
do_coredump fs/coredump.c:1126 [inline]
vfs_coredump+0x281a/0x54a0 fs/coredump.c:1195
get_signal+0x1f2a/0x21e0 kernel/signal.c:3097
arch_do_signal_or_restart+0x91/0x7e0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop kernel/entry/common.c:101 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
irqentry_exit+0x402/0xa10 kernel/entry/common.c:165
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fca7719e161
Code: 00 00 00 00 0f 1f 44 00 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fca77425fa0 RCX: 00007fca7719e159
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007fca7723506b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fca77426038 R14: 00007fca77425fa0 R15: 00007ffc1c8f7ea8