rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5830/2:b..l P5191/1:b..l
rcu: (detected by 1, t=10503 jiffies, g=76101, q=303 ncpus=2)
task:udevd state:R running task stack:23288 pid:5191 tgid:5191 ppid:1 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7050
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x74/0x80 kernel/locking/spinlock.c:194
spin_unlock_irqrestore include/linux/spinlock.h:406 [inline]
__wake_up_common_lock+0x190/0x1f0 kernel/sched/wait.c:127
sock_def_readable+0x1eb/0x530 net/core/sock.c:3611
__netlink_sendskb net/netlink/af_netlink.c:1263 [inline]
netlink_sendskb+0xa1/0x140 net/netlink/af_netlink.c:1269
netlink_unicast+0x397/0x9e0 net/netlink/af_netlink.c:1359
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec+0x18f/0x1d0 net/socket.c:737
__sock_sendmsg net/socket.c:752 [inline]
____sys_sendmsg+0x577/0x880 net/socket.c:2610
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2664
__sys_sendmsg net/socket.c:2696 [inline]
__do_sys_sendmsg net/socket.c:2701 [inline]
__se_sys_sendmsg net/socket.c:2699 [inline]
__x64_sys_sendmsg+0x19b/0x260 net/socket.c:2699
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f69250a7407
RSP: 002b:00007ffddfae4fe0 EFLAGS: 00000202 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f6925772880 RCX: 00007f69250a7407
RDX: 0000000000000000 RSI: 00007ffddfae5040 RDI: 0000000000000004
RBP: 0000562d1a00cb30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000077
R13: 0000562d19ffa9e0 R14: 0000000000000000 R15: 0000000000000000
task:syz-executor state:R running task stack:19496 pid:5830 tgid:5830 ppid:5812 task_flags:0x400140 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7193
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:748 [inline]
RIP: 0010:rcu_is_watching+0x8/0xb0 kernel/rcu/tree.c:751
Code: 32 21 03 eb cc 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 <53> 65 ff 05 30 7b fa 10 e8 6b 17 b6 09 89 c3 83 f8 08 73 65 49 bf
RSP: 0018:ffffc90003f2f5d8 EFLAGS: 00000202
RAX: ffffffff81f9ac45 RBX: ffffffff81f9ab0c RCX: 0000000000000000
RDX: ffff888028ff8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffea0001aefd37 R09: 1ffffd400035dfa6
R10: dffffc0000000000 R11: fffff9400035dfa7 R12: dffffc0000000000
R13: fffffffffffffffe R14: 0000000000000001 R15: 0000000000000001
rcu_read_unlock include/linux/rcupdate.h:866 [inline]
page_ref_add_unless include/linux/page_ref.h:239 [inline]
folio_ref_add_unless include/linux/page_ref.h:248 [inline]
folio_try_get+0x15f/0x340 include/linux/page_ref.h:264
find_get_entry mm/filemap.c:2076 [inline]
find_lock_entries+0x24f/0xa60 mm/filemap.c:2166
shmem_undo_range+0x254/0x1490 mm/shmem.c:1119
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
do_unlinkat+0x41d/0x5d0 fs/namei.c:5509
__do_sys_unlink fs/namei.c:5540 [inline]
__se_sys_unlink fs/namei.c:5538 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:5538
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7d7a18ecf7
RSP: 002b:00007ffdd7d034b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7d7a18ecf7
RDX: 00007ffdd7d034e0 RSI: 00007ffdd7d03570 RDI: 00007ffdd7d03570
RBP: 00007ffdd7d03570 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffdd7d04600
R13: 00007f7d7a213d7d R14: 0000000000105fd2 R15: 00007ffdd7d04640
rcu: rcu_preempt kthread starved for 10569 jiffies! g76101 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27584 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5258 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6866
__schedule_loop kernel/sched/core.c:6948 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6963
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 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 43 8e 2b 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000197e20 EFLAGS: 000002c2
RAX: 0000000001a4a63d RBX: ffffffff819717be RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d99cce1 RDI: ffffffff8be082e0
RBP: ffffc90000197f10 R08: ffff8880b873375b R09: 1ffff110170e66eb
R10: dffffc0000000000 R11: ffffed10170e66ec R12: ffffffff8fa23d70
R13: 1ffff11003b52b58 R14: 0000000000000001 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff888125d0c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000761b2000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x147