rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=11633, q=749 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294959845-4294949343), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g11633 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:27752 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 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:2167
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5993 Comm: syz.1.28 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x489/0x2970 arch/x86/kernel/unwind_orc.c:494
Code: e4 e9 a4 00 00 00 4c 89 e5 4c 89 64 24 28 48 ba 00 00 00 00 00 fc ff df 4c 8b 74 24 48 48 89 d8 4c 29 e0 48 89 c1 48 c1 f9 02 <48> c1 e8 3f 48 01 c8 48 83 e0 fe 4d 8d 3c 44 4c 89 f8 48 c1 e8 03
RSP: 0018:ffffc900036776d8 EFLAGS: 00000006
RAX: 0000000000000014 RBX: ffffffff8e6262f0 RCX: 0000000000000005
RDX: dffffc0000000000 RSI: ffffffff81dc8a1f RDI: ffffffff81dc8a91
RBP: ffffffff8e6262dc R08: ffffc90003677870 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: ffffffff8e6262dc
R13: ffffffff81dc8a91 R14: ffffffff81dc8a1f R15: ffffffff8e6262f4
FS:  00007f76cec846c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000002cfeb000 CR4: 00000000003506f0
Call Trace:
 <TASK>
 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
 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+0x96/0x780 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: 0033:0x7f76cdd8eba9
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:00007f76cec840e8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f76cdfd5fa8 RCX: 00007f76cdd8eba9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f76cdfd5fac
RBP: 00007f76cdfd5fa0 R08: 0000000000745d1e R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f76cdfd6038 R14: 00007fffd4118080 R15: 00007fffd4118168
 </TASK>