rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9652/1:b..l rcu: (detected by 1, t=10502 jiffies, g=40501, q=656 ncpus=2) task:udevd state:R running task stack:27480 pid:9652 tgid:9652 ppid:5183 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7108 irqentry_exit+0x36/0x90 kernel/entry/common.c:307 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_release+0x183/0x2f0 kernel/locking/lockdep.c:5896 Code: 0f c1 05 78 aa 34 12 83 f8 01 0f 85 1d 01 00 00 9c 58 f6 c4 02 0f 85 08 01 00 00 41 f7 c5 00 02 00 00 74 01 fb 48 8b 44 24 10 <65> 48 2b 05 8d 68 34 12 0f 85 58 01 00 00 48 83 c4 18 5b 41 5c 41 RSP: 0018:ffffc90002fe7870 EFLAGS: 00000206 RAX: e382d83949e7ae00 RBX: ffffffff8e5c4940 RCX: ffffc90002fe787c RDX: 0000000000000000 RSI: ffffffff8ddf4fdb RDI: ffffffff8c157ee0 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000122c7 R12: ffffffff816acad4 R13: 0000000000000206 R14: ffff8880551c0000 R15: 0000000000000001 rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x3f9/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204 getname_flags.part.0+0x4c/0x550 fs/namei.c:146 getname_flags+0x93/0xf0 include/linux/audit.h:322 getname include/linux/fs.h:2907 [inline] getname_maybe_null include/linux/fs.h:2914 [inline] getname_maybe_null include/linux/fs.h:2911 [inline] vfs_fstatat+0xe1/0xf0 fs/stat.c:370 __do_sys_newfstatat+0x97/0x120 fs/stat.c:542 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1536d11b0a RSP: 002b:00007ffdb8c6bec8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000000000006180 RCX: 00007f1536d11b0a RDX: 00007ffdb8c6bef0 RSI: 00005650bb3a39b0 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000000000000000 R09: 00005650bb3a1930 R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00005650bb3a39b0 R15: 00005650bb40cce0 rcu: rcu_preempt kthread timer wakeup didn't happen for 10389 jiffies! g40501 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=25182 rcu: rcu_preempt kthread starved for 10390 jiffies! g40501 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 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:I stack:28376 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2054 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2256 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9688 Comm: syz.0.926 Not tainted 6.16.0-rc3-syzkaller-00190-g67a993863163 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:lock_release+0x24/0x2f0 kernel/locking/lockdep.c:5879 Code: 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 41 55 41 54 49 89 f4 53 48 89 fb 48 83 ec 18 65 48 8b 05 f9 69 34 12 48 89 44 24 10 <31> c0 0f 1f 44 00 00 65 8b 05 12 6a 34 12 83 f8 07 0f 87 38 02 00 RSP: 0018:ffffc90000007d48 EFLAGS: 00000096 RAX: 26c55cb516431900 RBX: ffffffff8e5c4940 RCX: ffffffff89937857 RDX: ffff888028c04880 RSI: ffffffff8993767c RDI: ffffffff8e5c4940 RBP: ffff8880285a6c00 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: ffffffff8993767c R13: 185974366a5d0c15 R14: 0000000000000002 R15: ffff8880285a7010 FS: 00007feee11986c0(0000) GS:ffff888124752000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f211dd53d58 CR3: 00000000570b6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:341 [inline] rcu_read_unlock include/linux/rcupdate.h:871 [inline] advance_sched+0x6f1/0xc80 net/sched/sch_taprio.c:987 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1825 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x17/0x70 kernel/kcov.c:217 Code: 03 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 65 48 8b 15 98 bf 10 12 65 8b 05 a9 bf 10 12 00 01 ff 00 74 1d f6 c4 01 74 43 a9 00 00 0f 00 75 3c a9 00 00 RSP: 0018:ffffc9000238f948 EFLAGS: 00000286 RAX: 0000000080000000 RBX: 00000000fffffff5 RCX: ffffffff899a063d RDX: ffff888028c04880 RSI: ffffffff899a0646 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000000 R10: 00000000fffffff5 R11: 0000000000000001 R12: ffff888029dfe0e8 R13: 000000007ffff000 R14: 000000007ffff000 R15: 0000000000000000 netlink_recvmsg+0x6b6/0xa90 net/netlink/af_netlink.c:1975 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0x1f6/0x250 net/socket.c:1039 sock_read_iter+0x2b9/0x3b0 net/socket.c:1109 io_iter_do_read io_uring/rw.c:828 [inline] __io_read+0x354/0x14a0 io_uring/rw.c:941 io_read+0x1e/0x70 io_uring/rw.c:1020 __io_issue_sqe+0xe8/0x7c0 io_uring/io_uring.c:1738 io_issue_sqe+0x86/0xe50 io_uring/io_uring.c:1761 io_queue_sqe io_uring/io_uring.c:1968 [inline] io_submit_sqe io_uring/io_uring.c:2224 [inline] io_submit_sqes+0x92d/0x2580 io_uring/io_uring.c:2337 __do_sys_io_uring_enter+0xd6a/0x1630 io_uring/io_uring.c:3404 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7feee038e929 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:00007feee1198038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007feee05b5fa0 RCX: 00007feee038e929 RDX: 0000000000000000 RSI: 00000000000047ba RDI: 000000000000000a RBP: 00007feee0410b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007feee05b5fa0 R15: 00007fffd00c41d8