INFO: task syz.6.3418:19403 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.3418 state:D stack:28856 pid:19403 tgid:19401 ppid:10632 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x125c/0x6730 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0xdd/0x2c0 kernel/sched/core.c:7326
cgroup_lock_and_drain_offline+0x383/0x800 kernel/cgroup/cgroup.c:3275
cgroup1_get_tree+0xc2/0x1620 kernel/cgroup/cgroup-v1.c:1265
vfs_get_tree+0x92/0x320 fs/super.c:1694
fc_mount fs/namespace.c:1198 [inline]
do_new_mount_fc fs/namespace.c:3765 [inline]
do_new_mount fs/namespace.c:3841 [inline]
path_mount+0x7d0/0x23d0 fs/namespace.c:4161
do_mount fs/namespace.c:4174 [inline]
__do_sys_mount fs/namespace.c:4390 [inline]
__se_sys_mount fs/namespace.c:4367 [inline]
__x64_sys_mount+0x293/0x310 fs/namespace.c:4367
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f119b99de99
RSP: 002b:00007f119c791028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f119bc25fa0 RCX: 00007f119b99de99
RDX: 00002000000000c0 RSI: 0000200000000000 RDI: 0000000000000000
RBP: 00007f119ba33eaf R08: 0000200000000400 R09: 0000000000000000
R10: 0000000000010012 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f119bc26038 R14: 00007f119bc25fa0 R15: 00007ffc212fd5b8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8ebe6180 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by getty/5362:
#0: ffff888037f990a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14e0 drivers/tty/n_tty.c:2211
3 locks held by syz.2.4167/22236:
#0: ffff88807fe74630 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
#1: ffff888073c1e450 (sb_writers#10){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
#2: ffff8880377f9480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:336
4 locks held by syz.7.4260/22518:
=============================================
NMI backtrace for cpu 0
CPU: 0 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 06/10/2026
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:122
nmi_trigger_cpumask_backtrace+0x21c/0x2a0 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [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+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
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: 22518 Comm: syz.7.4260 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/10/2026
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:check_preemption_disabled+0x2c/0xe0 lib/smp_processor_id.c:19
Code: 55 53 48 83 ec 08 65 8b 1d d5 f5 a9 08 65 f7 05 c6 f5 a9 08 ff ff ff 7f 74 0f 48 83 c4 08 89 d8 5b 5d 41 5c c3 cc cc cc cc 9c <58> f6 c4 02 74 ea 65 4c 8b 25 8e f5 a9 08 48 89 fd 41 f6 44 24 2f
RSP: 0018:ffffc90005826ad8 EFLAGS: 00000046
RAX: 00000000ffffffff RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8e29a68e RDI: ffffffff8c401280
RBP: ffff88802c584a80 R08: 000000009538c3b1 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: 00000000ffffffff
R13: 0000000000000246 R14: ffffffff82831f39 R15: 0000000000000000
FS: 00007f854467d6c0(0000) GS:ffff888123ee8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555590e07168 CR3: 00000000a7354000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
lock_is_held_type+0x60/0x140 kernel/locking/lockdep.c:5939
get_mem_cgroup_from_mm+0x12e/0x5e0 mm/memcontrol.c:1142
__mem_cgroup_charge+0x1a/0x1c0 mm/memcontrol.c:5142
mem_cgroup_charge include/linux/memcontrol.h:641 [inline]
shmem_alloc_and_add_folio+0x451/0xd40 mm/shmem.c:1959
shmem_get_folio_gfp+0x6ad/0x1910 mm/shmem.c:2502
shmem_get_folio mm/shmem.c:2608 [inline]
shmem_write_begin+0x1a4/0x420 mm/shmem.c:3239
generic_perform_write+0x292/0xa40 mm/filemap.c:4358
shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3414
__kernel_write_iter+0x2ac/0x930 fs/read_write.c:621
dump_emit_page fs/coredump.c:1298 [inline]
dump_user_range+0x3f9/0xad0 fs/coredump.c:1372
elf_core_dump+0x2d68/0x3d20 fs/binfmt_elf.c:2109
coredump_write fs/coredump.c:1052 [inline]
do_coredump fs/coredump.c:1131 [inline]
vfs_coredump+0x294b/0x56f0 fs/coredump.c:1200
get_signal+0x1f2a/0x21e0 kernel/signal.c:3031
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+0x402/0xa00 kernel/entry/common.c:165
asm_exc_general_protection+0x26/0x30 arch/x86/include/asm/idtentry.h:589
RIP: 0033:0x7f854379dea1
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:0000200000000110 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f8543a25fa0 RCX: 00007f854379de99
RDX: 0000200000000180 RSI: 0000200000000110 RDI: 0000000000c00000
RBP: 00007f8543833eaf R08: 0000200000000240 R09: 0000200000000240
R10: 0000200000000200 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f8543a26038 R14: 00007f8543a25fa0 R15: 00007ffddecd90a8