rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3547/1:b..l
	(detected by 0, t=10502 jiffies, g=6877, q=115)
task:udevd           state:R  running task     stack:26048 pid: 3547 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780
 irqentry_exit+0x63/0x70 kernel/entry/common.c:432
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:do_inode_permission fs/namei.c:457 [inline]
RIP: 0010:inode_permission+0x5a/0x480 fs/namei.c:526
Code: 2c 24 0f 85 cf 00 00 00 e8 93 a3 ad 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:ffffc90002e3fa18 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: 0000000000000081 RCX: ffff88807d0dbb80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888022d70d9a R08: dffffc0000000000 R09: fffff520005c7f8e
R10: fffff520005c7f8e R11: 1ffff920005c7f8c R12: 1ffff110045ae1b3
R13: ffffffff8bfc9bc0 R14: ffff888022d70d98 R15: ffffffff8bfc9bc0
 may_lookup fs/namei.c:1689 [inline]
 link_path_walk+0x277/0xd40 fs/namei.c:2245
 path_lookupat+0x9d/0x440 fs/namei.c:2454
 filename_lookup+0x1e2/0x4f0 fs/namei.c:2484
 user_path_at_empty+0x40/0x190 fs/namei.c:2883
 do_readlinkat+0xd4/0x480 fs/stat.c:442
 __do_sys_readlink fs/stat.c:475 [inline]
 __se_sys_readlink fs/stat.c:472 [inline]
 __x64_sys_readlink+0x7b/0x90 fs/stat.c:472
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f5a1ad70d47
RSP: 002b:00007ffdd4dd8bc8 EFLAGS: 00000202 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 0000558c799201af RCX: 00007f5a1ad70d47
RDX: 0000000000000200 RSI: 00007ffdd4dd8bd8 RDI: 00007ffdd4dd8dd8
RBP: 0000558c91464910 R08: 0000000000000000 R09: 00007ffdd4dd8548
R10: 0000000000000010 R11: 0000000000000202 R12: 00007ffdd4dd8bd8
R13: 00007ffdd4dd8dd8 R14: 0000558c91478f30 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10489 jiffies! g6877 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=2281
rcu: rcu_preempt kthread starved for 10490 jiffies! g6877 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27808 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
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: 4279 Comm: syz.2.9 Not tainted 5.15.181-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:__clear_user+0x47/0x70 arch/x86/lib/usercopy_64.c:24
Code: ac fd 0f 01 cb 89 d8 83 e0 07 48 c1 eb 03 4c 89 f7 48 89 d9 48 85 c9 74 19 66 2e 0f 1f 84 00 00 00 00 00 48 c7 07 00 00 00 00 <48> 83 c7 08 ff c9 75 f1 48 89 c1 85 c9 74 0a c6 07 00 48 ff c7 ff
RSP: 0018:ffffc9000337fb08 EFLAGS: 00040202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000000008
RDX: ffffc9000cef1000 RSI: 000000000007ffff RDI: 00007f0d8cc7ff00
RBP: ffffc9000337fcb0 R08: dffffc0000000000 R09: ffffed100437d771
R10: ffffed100437d771 R11: 1ffff1100437d770 R12: 0000000000000007
R13: ffff888021bed308 R14: 00007f0d8cc7ff00 R15: ffff888021bebb80
FS:  00007f0d8cc806c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f405629bf98 CR3: 000000007e1f4000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 xsave_to_user_sigframe arch/x86/include/asm/fpu/internal.h:346 [inline]
 copy_fpregs_to_sigframe arch/x86/kernel/fpu/signal.c:141 [inline]
 copy_fpstate_to_sigframe+0x454/0xb90 arch/x86/kernel/fpu/signal.c:203
 get_sigframe arch/x86/kernel/signal.c:295 [inline]
 __setup_rt_frame arch/x86/kernel/signal.c:471 [inline]
 setup_rt_frame arch/x86/kernel/signal.c:780 [inline]
 handle_signal arch/x86/kernel/signal.c:824 [inline]
 arch_do_signal_or_restart+0x67a/0x1300 arch/x86/kernel/signal.c:869
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0d8ee18967
Code: ff ff 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
RSP: 002b:00007f0d8cc800e8 EFLAGS: 00000246
RAX: 00000000000000ca RBX: 00007f0d8f03ffa8 RCX: 00007f0d8ee18969
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0d8f03ffa8
RBP: 00007f0d8f03ffa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0d8f03ffac
R13: 0000000000000000 R14: 00007fff461a1920 R15: 00007fff461a1a08
 </TASK>