rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12332/1:b..l
rcu: (detected by 0, t=10503 jiffies, g=54121, q=265 ncpus=2)
task:cmp state:R running task stack:24232 pid:12332 ppid:12304 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009
irqentry_exit+0x67/0x70 kernel/entry/common.c:438
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:do_inode_permission fs/namei.c:460 [inline]
RIP: 0010:inode_permission+0x5e/0x480 fs/namei.c:529
Code: 2c 24 0f 85 cf 00 00 00 e8 0f ca 96 ff 4d 89 fd 49 8d 6e 02 49 89 ec 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df 41 0f b6 04 04 <84> c0 0f 85 33 03 00 00 44 0f b7 7d 00 44 89 fe 83 e6 01 31 ff e8
RSP: 0018:ffffc9000441f838 EFLAGS: 00000a06
RAX: 0000000000000000 RBX: 0000000000000081 RCX: ffff888053ab0000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888148dbaab2 R08: ffff88801d65c7a0 R09: ffff88801fceabc0
R10: ffff88801d65c7a0 R11: ffff88801fceabc0 R12: 1ffff110291b7556
R13: ffffffff8ce64540 R14: ffff888148dbaab0 R15: ffffffff8ce64540
may_lookup fs/namei.c:1728 [inline]
link_path_walk+0x286/0xe00 fs/namei.c:2279
path_openat+0x283/0x3190 fs/namei.c:3793
do_filp_open+0x1c5/0x3d0 fs/namei.c:3824
do_sys_openat2+0x12c/0x1c0 fs/open.c:1421
do_sys_open fs/open.c:1436 [inline]
__do_sys_openat fs/open.c:1452 [inline]
__se_sys_openat fs/open.c:1447 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1447
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f6eddb3e0ba
RSP: 002b:00007ffda9a7b438 EFLAGS: 00000206 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffda9a7b4b0 RCX: 00007f6eddb3e0ba
RDX: 0000000000080000 RSI: 00007ffda9a7b4b0 RDI: 00000000ffffff9c
RBP: 00007ffda9a7b4a0 R08: 00007ffda9a7b6a7 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000018
R13: 00007f6eddb1a000 R14: 00007ffda9a7b6c0 R15: 0000000000000000
rcu: rcu_preempt kthread starved for 10537 jiffies! g54121 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:27752 pid:17 ppid:2 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x160/0x280 kernel/time/timer.c:2168
rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12329 Comm: syz.4.1949 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:stack_trace_consume_entry+0x136/0x270 kernel/stacktrace.c:95
Code: 48 89 de 49 89 37 41 8b 18 41 0f b6 44 15 00 84 c0 0f 85 2f 01 00 00 41 3b 1e 0f 92 c0 48 83 c4 18 5b 41 5c 41 5d 41 5e 41 5f <5d> c3 44 89 c1 80 e1 07 80 c1 03 38 c1 0f 8c eb fe ff ff 48 89 fb
RSP: 0018:ffffc900037a7778 EFLAGS: 00000096
RAX: 0000000000000001 RBX: ffffc900037a7840 RCX: ffff88805d770000
RDX: dffffc0000000000 RSI: ffffffff81dcd606 RDI: ffffc900037a7840
RBP: 1ffff920006f4f0a R08: ffffc900037a7850 R09: 0000000000000002
R10: 0000000000000004 R11: 0000000000000002 R12: ffffffff81dcd606
R13: ffffc900037a7b98 R14: ffffffff81746d20 R15: ffffc900037a7788
FS: 00007f73c3d8d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000404030 CR3: 00000000238c0000 CR4: 00000000003506e0
Call Trace:
arch_stack_walk+0x138/0x190 arch/x86/kernel/stacktrace.c:27
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x280 mm/slub.c:3852
__sigqueue_free kernel/signal.c:461 [inline]
collect_signal kernel/signal.c:604 [inline]
__dequeue_signal+0x52b/0x680 kernel/signal.c:626
dequeue_signal+0xe9/0x4b0 kernel/signal.c:649
get_signal+0x551/0x1400 kernel/signal.c:2782
arch_do_signal_or_restart+0x9c/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f73c2f8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f73c3d8d0e8 EFLAGS: 00000246
RAX: fffffffffffffffc RBX: 00007f73c31e5fa8 RCX: 00007f73c2f8f749
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f73c31e5fa8
RBP: 00007f73c31e5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f73c31e6038 R14: 00007fffe08e9a90 R15: 00007fffe08e9b78