INFO: task udevd:438 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:0 pid:438 tgid:438 ppid:110 flags:0x00000000
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285
bdev_open+0xd5/0xd60 block/bdev.c:926
blkdev_open+0x3d1/0x560 block/fops.c:627
do_dentry_open+0x97b/0x1510 fs/open.c:960
vfs_open+0x86/0x230 fs/open.c:1090
do_open fs/namei.c:3774 [inline]
path_openat+0x2b6c/0x34b0 fs/namei.c:3933
do_filp_open+0x1c6/0x3e0 fs/namei.c:3960
do_sys_openat2+0x12c/0x1c0 fs/open.c:1438
do_sys_open fs/open.c:1453 [inline]
__do_sys_openat fs/open.c:1469 [inline]
__se_sys_openat fs/open.c:1464 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1464
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f7e658a7407
RSP: 002b:00007ffdda450db0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f7e66093880 RCX: 00007f7e658a7407
RDX: 00000000000a0800 RSI: 00005631217ae6a0 RDI: ffffffffffffff9c
RBP: 00005631215672c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005631217ad540
R13: 00005631217a80f0 R14: 0000000000000000 R15: 00005631217ad540
INFO: task syz.3.1055:3770 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1055 state:D stack:0 pid:3770 tgid:3769 ppid:291 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5945 [inline]
__schedule+0x1322/0x1df0 kernel/sched/core.c:7791
__schedule_loop kernel/sched/core.c:7872 [inline]
schedule+0xc6/0x240 kernel/sched/core.c:7887
io_schedule+0x89/0xe0 kernel/sched/core.c:8699
folio_wait_bit_common+0x6ae/0x910 mm/filemap.c:1354
folio_put_wait_locked mm/filemap.c:1518 [inline]
do_read_cache_folio+0x14d/0x4d0 mm/filemap.c:3970
read_cache_folio+0x54/0x90 mm/filemap.c:4020
read_mapping_folio include/linux/pagemap.h:1021 [inline]
read_part_sector+0xcc/0x250 block/partitions/core.c:716
msdos_partition+0x118/0x3000 block/partitions/msdos.c:592
check_partition block/partitions/core.c:138 [inline]
blk_add_partitions block/partitions/core.c:583 [inline]
bdev_disk_changed+0x81c/0x1610 block/partitions/core.c:687
loop_reread_partitions+0x64/0x110 drivers/block/loop.c:467
loop_configure+0xfd8/0x1310 drivers/block/loop.c:1074
lo_ioctl+0x802/0x1d50 drivers/block/loop.c:-1
blkdev_ioctl+0x546/0x680 block/ioctl.c:699
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0x135/0x1b0 fs/ioctl.c:893
__x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893
x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f477138f6c9
RSP: 002b:00007f477220d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f47715e5fa0 RCX: 00007f477138f6c9
RDX: 0000200000000080 RSI: 0000000000004c0a RDI: 0000000000000003
RBP: 00007f4771411f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f47715e6038 R14: 00007f47715e5fa0 R15: 00007ffd232c0888
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xd8f/0xed0 kernel/hung_task.c:423
kthread+0x2ca/0x370 kernel/kthread.c:389
ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 0b5ffdee5fcd2f7749818d1ff954e9c21353764e
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:scale_rt_capacity kernel/sched/fair.c:10240 [inline]
RIP: 0010:update_cpu_capacity kernel/sched/fair.c:10266 [inline]
RIP: 0010:update_group_capacity+0x343/0x9f0 kernel/sched/fair.c:10293
Code: 48 c1 e8 03 80 3c 30 00 74 12 48 89 df e8 75 be 7e 00 48 be 00 00 00 00 00 fc ff df 48 8b 1b 4c 89 e8 48 c1 e8 03 80 3c 30 00 <74> 12 4c 89 ef e8 53 be 7e 00 48 be 00 00 00 00 00 fc ff df 49 29
RSP: 0018:ffffc90000007740 EFLAGS: 00000246
RAX: 1ffffffff0ded970 RBX: 0000000000000000 RCX: ffffffff87215540
RDX: 0000000000000100 RSI: dffffc0000000000 RDI: 0000000000000000
RBP: ffffc90000007810 R08: ffff888103e5172f R09: 1ffff110207ca2e5
R10: dffffc0000000000 R11: ffffed10207ca2e6 R12: 0000000000000000
R13: ffffffff86f6cb80 R14: 0000000000000400 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efcad311000 CR3: 000000011098e000 CR4: 00000000003526b0
DR0: 00000000000000f9 DR1: 0000000000000b7f DR2: 0000008000000006
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
update_sd_lb_stats kernel/sched/fair.c:11313 [inline]
sched_balance_find_src_group kernel/sched/fair.c:11576 [inline]
sched_balance_rq+0x89b/0x5060 kernel/sched/fair.c:12023
sched_balance_domains+0x4b4/0xa10 kernel/sched/fair.c:12495
_nohz_idle_balance+0x3e3/0x5a0 kernel/sched/fair.c:12946
nohz_idle_balance kernel/sched/fair.c:12989 [inline]
sched_balance_softirq+0x8a/0x170 kernel/sched/fair.c:13224
handle_softirqs+0x1ab/0x630 kernel/softirq.c:621
__do_softirq kernel/softirq.c:659 [inline]
invoke_softirq kernel/softirq.c:476 [inline]
__irq_exit_rcu+0x48/0xc0 kernel/softirq.c:708
irq_exit_rcu+0xd/0x30 kernel/softirq.c:720
instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
sysvec_call_function_single+0x7f/0x90 arch/x86/kernel/smp.c:266
asm_sysvec_call_function_single+0x1f/0x30 arch/x86/include/asm/idtentry.h:709
RIP: 0010:pv_native_safe_halt+0x17/0x20 arch/x86/kernel/paravirt.c:106
Code: cc cc cc b8 74 59 34 e5 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d c3 e2 39 00 f3 0f 1e fa 55 48 89 e5 fb f4 <5d> e9 d3 54 02 00 cc cc cc b8 00 00 00 00 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff87207da0 EFLAGS: 000002c2
RAX: ffff8881f6e00000 RBX: ffffffff87215540 RCX: ffffffff858d70be
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000003a48a4
RBP: ffffffff87207da0 R08: ffff8881f6e39733 R09: 1ffff1103edc72e6
R10: dffffc0000000000 R11: ffffed103edc72e7 R12: 1ffffffff0e42aa8
R13: 0000000000000000 R14: 0000000000000000 R15: ffffffff87cb2128
arch_safe_halt arch/x86/include/asm/paravirt.h:112 [inline]
default_idle+0x17/0x30 arch/x86/kernel/process.c:754
arch_cpu_idle+0xd/0x20 arch/x86/kernel/process.c:791
default_idle_call+0x3f/0x80 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x1a0/0x470 kernel/sched/idle.c:326
cpu_startup_entry+0x48/0x70 kernel/sched/idle.c:424
rest_init+0x10b/0x130 init/main.c:748
start_kernel+0x46a/0x4bb init/main.c:1135
x86_64_start_reservations+0x2e/0x30 arch/x86/kernel/head64.c:507
x86_64_start_kernel+0x6a/0x7b arch/x86/kernel/head64.c:488
common_startup_64+0x13b/0x157