rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5176/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=29037, q=241 ncpus=2)
task:klogd state:R running task stack:24680 pid:5176 tgid:5176 ppid:1 task_flags:0x400100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7190
irqentry_exit+0x1d8/0x8c0 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__kasan_check_byte+0x19/0x50 mm/kasan/common.c:578
Code: 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 41 54 49 89 f4 55 48 89 fd 53 e8 8d 25 00 00 89 c3 84 c0 74 0b <89> d8 5b 5d 41 5c e9 bc da 52 09 4c 89 e1 48 89 ef 31 d2 be 01 00
RSP: 0018:ffffc900049ff3b0 EFLAGS: 00000202
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff816cc711 RDI: fffffbfff1c792d4
RBP: ffffffff8e3c96a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000006cec R12: ffffffff816cc711
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire kernel/locking/lockdep.c:5842 [inline]
lock_acquire+0xfc/0x330 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
unwind_next_frame+0xd1/0x20b0 arch/x86/kernel/unwind_orc.c:495
__unwind_start+0x45f/0x7f0 arch/x86/kernel/unwind_orc.c:773
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0x73/0x100 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
kasan_save_stack+0x33/0x60 mm/kasan/common.c:57
kasan_save_track+0x14/0x30 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__do_kmalloc_node mm/slub.c:5657 [inline]
__kmalloc_node_track_caller_noprof+0x353/0x930 mm/slub.c:5764
kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:608
__alloc_skb+0x186/0x410 net/core/skbuff.c:690
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xe0/0x860 net/core/skbuff.c:6714
sock_alloc_send_pskb+0x7f9/0x980 net/core/sock.c:2995
unix_dgram_sendmsg+0x3bc/0x1830 net/unix/af_unix.c:2130
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x4a3/0x520 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b77bda407
RSP: 002b:00007fff4d3c68e0 EFLAGS: 00000202 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f9b77a8ac80 RCX: 00007f9b77bda407
RDX: 0000000000000043 RSI: 00007fff4d3c6a20 RDI: 0000000000000003
RBP: 00007fff4d3c6e50 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000202 R12: 00007fff4d3c6e68
R13: 00007fff4d3c6a20 R14: 0000000000000028 R15: 00007fff4d3c6a20
rcu: rcu_preempt kthread starved for 10508 jiffies! g29037 f0x0 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:27952 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5256 [inline]
__schedule+0x1139/0x6150 kernel/sched/core.c:6863
__schedule_loop kernel/sched/core.c:6945 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6960
schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x1ea/0xaf0 kernel/rcu/tree.c:2083
rcu_gp_kthread+0x26d/0x380 kernel/rcu/tree.c:2285
kthread+0x3c5/0x780 kernel/kthread.c:463
ret_from_fork+0x983/0xb10 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:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9475 Comm: syz.0.891 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:hlock_class kernel/locking/lockdep.c:234 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4854 [inline]
RIP: 0010:__lock_acquire+0x20c/0x2890 kernel/locking/lockdep.c:5187
Code: 8b 56 20 81 e2 ff 1f 00 00 09 d0 41 89 46 20 8b 84 24 c0 00 00 00 41 89 46 24 4c 89 c8 25 ff 1f 00 00 48 0f a3 05 34 b9 1f 14 <0f> 83 db 05 00 00 48 8d 04 80 48 8d 04 80 48 8d 04 c5 60 9a b9 95
RSP: 0000:ffffc9000c3a6e08 EFLAGS: 00000003
RAX: 0000000000000007 RBX: 0000000000000000 RCX: 0000000000020000
RDX: 0000000000000007 RSI: 0000000000000000 RDI: ffffffff8e3c96a0
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000007
R10: 0000000000000000 R11: ffff8880357c8b30 R12: ffff8880357c8000
R13: ffffffff8e3c96a0 R14: ffff8880357c8b58 R15: 0000000000000000
FS: 000055557a7fb500(0000) GS:ffff8881248f4000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1fd1fd6760 CR3: 000000007a6bb000 CR4: 00000000003526f0
Call Trace:
lock_acquire kernel/locking/lockdep.c:5868 [inline]
lock_acquire+0x179/0x330 kernel/locking/lockdep.c:5825
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:867 [inline]
shrink_slab_memcg mm/shrinker.c:515 [inline]
shrink_slab+0x676/0x12b0 mm/shrinker.c:628
shrink_node_memcgs mm/vmscan.c:6022 [inline]
shrink_node+0x918/0x3bb0 mm/vmscan.c:6061
shrink_zones mm/vmscan.c:6300 [inline]
do_try_to_free_pages+0x362/0x1920 mm/vmscan.c:6362
try_to_free_mem_cgroup_pages+0x31b/0x740 mm/vmscan.c:6690
try_charge_memcg+0x42a/0xd30 mm/memcontrol.c:2388
try_charge mm/memcontrol.c:2530 [inline]
charge_memcg+0x8a/0x230 mm/memcontrol.c:4728
mem_cgroup_swapin_charge_folio+0xeb/0x470 mm/memcontrol.c:4814
__read_swap_cache_async+0x397/0x500 mm/swap_state.c:481
swap_cluster_readahead+0x432/0x770 mm/swap_state.c:646
swapin_readahead+0x160/0x1220 mm/swap_state.c:821
do_swap_page+0x962/0x64a0 mm/memory.c:4753
handle_pte_fault mm/memory.c:6276 [inline]
__handle_mm_fault+0x19cb/0x2bb0 mm/memory.c:6411
handle_mm_fault+0x3fe/0xad0 mm/memory.c:6580
do_user_addr_fault+0x7a6/0x1370 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x64/0xc0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f1fd1c4d75c
Code: 23 83 c0 01 44 39 d0 75 dc 48 89 f0 25 ff 1f 00 00 49 89 34 c1 41 88 3c 00 31 c0 c3 66 90 41 38 3c 10 74 0b 41 88 3c 10 31 c0 <49> 89 34 d1 c3 b8 01 00 00 00 c3 66 0f 1f 84 00 00 00 00 00 48 83
RSP: 002b:00007ffc68e08218 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00007f1fd2b15720 RCX: ffffffff8b75a8ec
RDX: 00000000000008ec RSI: ffffffff845e48ec RDI: 000000000000000b
RBP: ffffffff845e48ec R08: 00007f1fd1fd0000 R09: 00007f1fd1fd2000
R10: 00000000845e48f0 R11: 000000000000000b R12: 000000000000000b
R13: 0000000000000000 R14: ffffffff845e4543 R15: 0000000000000033