rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3490/1:b..l P13954/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=58641, q=680 ncpus=2)
task:syz-executor state:R running task stack:21224 pid:13954 ppid:13948 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6866
preempt_schedule+0xab/0xc0 kernel/sched/core.c:6890
preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45
unwind_next_frame+0x200f/0x2970 arch/x86/kernel/unwind_orc.c:672
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__reset_page_owner+0x4e/0x190 mm/page_owner.c:149
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2475
release_pages+0x1fa0/0x2220 mm/swap.c:1022
__folio_batch_release+0x71/0xe0 mm/swap.c:1042
folio_batch_release include/linux/pagevec.h:83 [inline]
shmem_undo_range+0x5d0/0x1a40 mm/shmem.c:1027
shmem_truncate_range mm/shmem.c:1136 [inline]
shmem_evict_inode+0x273/0xa70 mm/shmem.c:1265
evict+0x486/0x870 fs/inode.c:705
do_unlinkat+0x37b/0x570 fs/namei.c:4406
__do_sys_unlink fs/namei.c:4447 [inline]
__se_sys_unlink fs/namei.c:4445 [inline]
__x64_sys_unlink+0x49/0x50 fs/namei.c:4445
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: 0033:0x7f38d398e577
RSP: 002b:00007fff805e92c8 EFLAGS: 00000202 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f38d398e577
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007fff805e9380
RBP: 00007fff805e9380 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff805ea410
R13: 00007f38d3a11d7d R14: 000055557067f4a8 R15: 0000000000000005
task:kworker/u4:12 state:R running task stack:22280 pid:3490 ppid:2 flags:0x00004000
Workqueue: bat_events batadv_nc_worker
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
preempt_schedule_notrace+0xce/0x110 kernel/sched/core.c:6959
preempt_schedule_notrace_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:46
rcu_is_watching+0x7a/0xb0 kernel/rcu/tree.c:701
rcu_read_unlock include/linux/rcupdate.h:815 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x208/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
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: rcu_preempt kthread starved for 1057 jiffies! g58641 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:26728 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: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
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 PID: 14366 Comm: syz.8.3607 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x17/0x80 kernel/kcov.c:320
Code: 48 89 44 11 20 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 f3 0f 1e fa 48 8b 04 24 65 48 8b 0d 10 24 7e 7e 65 8b 15 11 24 7e 7e <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00
RSP: 0018:ffffc90000007440 EFLAGS: 00000246
RAX: ffffffff81321afa RBX: ffffc90000007500 RCX: ffff888054fe5a00
RDX: 0000000080000101 RSI: ffffffff81d0c34e RDI: 0000000000000000
RBP: ffffc900000074d0 R08: ffff888054fe5a00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000100 R12: ffffffff81d0c34e
R13: 00000000000000f0 R14: ffffffff81746c80 R15: ffffc90000007448
FS: 00007f7b744ce6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555a4af5c8 CR3: 0000000058437000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
arch_stack_walk+0x12a/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_slab_alloc+0x6c/0x80 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
kmem_cache_alloc_node+0x150/0x330 mm/slub.c:3540
__alloc_skb+0x108/0x2c0 net/core/skbuff.c:640
skb_copy+0x13d/0x7a0 net/core/skbuff.c:1983
mac80211_hwsim_tx_frame_no_nl+0xc81/0x1170 drivers/net/wireless/virtual/mac80211_hwsim.c:1840
mac80211_hwsim_tx_frame+0x1b5/0x200 drivers/net/wireless/virtual/mac80211_hwsim.c:2176
mac80211_hwsim_beacon_tx+0x3e9/0x780 drivers/net/wireless/virtual/mac80211_hwsim.c:2269
__iterate_interfaces+0x243/0x500 net/mac80211/util.c:766
ieee80211_iterate_active_interfaces_atomic+0xdb/0x180 net/mac80211/util.c:802
mac80211_hwsim_beacon+0xbb/0x1b0 drivers/net/wireless/virtual/mac80211_hwsim.c:2295
__run_hrtimer kernel/time/hrtimer.c:1750 [inline]
__hrtimer_run_queues+0x51e/0xc40 kernel/time/hrtimer.c:1814
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1831
handle_softirqs+0x280/0x820 kernel/softirq.c:578
__do_softirq kernel/softirq.c:612 [inline]
invoke_softirq kernel/softirq.c:452 [inline]
__irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661
irq_exit_rcu+0x9/0x20 kernel/softirq.c:673
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:unwind_next_frame+0x4c/0x2970 arch/x86/kernel/unwind_orc.c:470
Code: e8 f9 eb 4a 00 49 8d 5c 24 48 48 89 d8 48 c1 e8 03 48 89 44 24 40 42 80 3c 28 00 74 08 48 89 df e8 59 45 a2 00 48 89 5c 24 20 <4d> 8b 7c 24 48 4d 8d 74 24 38 4c 89 f0 48 c1 e8 03 48 89 44 24 68
RSP: 0018:ffffc9000b90f510 EFLAGS: 00000246
RAX: 1ffff92001721ed2 RBX: ffffc9000b90f690 RCX: 0000000000080000
RDX: ffffc9000ee52000 RSI: 0000000000003c0d RDI: 0000000000003c0e
RBP: ffffc9000b90f6d8 R08: ffffc9000b90f601 R09: 0000000000000000
R10: ffffc9000b90f648 R11: fffff52001721ed5 R12: ffffc9000b90f648
R13: dffffc0000000000 R14: 1ffff92001721ec9 R15: ffffc9000b90f650
__unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:128
__reset_page_owner+0x4e/0x190 mm/page_owner.c:149
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1154 [inline]
free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
discard_slab mm/slub.c:2127 [inline]
__unfreeze_partials+0x1cf/0x210 mm/slub.c:2667
put_cpu_partial+0x17c/0x250 mm/slub.c:2743
__slab_free+0x31d/0x410 mm/slub.c:3700
qlink_free mm/kasan/quarantine.c:166 [inline]
qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185
kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767
slab_alloc_node mm/slub.c:3495 [inline]
__kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3534
kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098
kmalloc include/linux/slab.h:600 [inline]
kzalloc include/linux/slab.h:721 [inline]
apparmor_sk_alloc_security+0x77/0x100 security/apparmor/lsm.c:860
security_sk_alloc+0x6e/0xa0 security/security.c:4464
sk_prot_alloc+0x101/0x210 net/core/sock.c:2099
sk_alloc+0x3a/0x360 net/core/sock.c:2152
unix_create1+0xb0/0x790 net/unix/af_unix.c:-1
unix_create+0x154/0x1f0 net/unix/af_unix.c:1084
__sock_create+0x4a6/0x940 net/socket.c:1571
sock_create net/socket.c:1627 [inline]
__sys_socketpair+0x236/0x550 net/socket.c:1782
__do_sys_socketpair net/socket.c:1831 [inline]
__se_sys_socketpair net/socket.c:1828 [inline]
__x64_sys_socketpair+0x9b/0xb0 net/socket.c:1828
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: 0033:0x7f7b7358efc9
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:00007f7b744ce038 EFLAGS: 00000246 ORIG_RAX: 0000000000000035
RAX: ffffffffffffffda RBX: 00007f7b737e5fa0 RCX: 00007f7b7358efc9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001
RBP: 00007f7b73611f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7b737e6038 R14: 00007f7b737e5fa0 R15: 00007ffc09021458