rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12391/1:b..l P12394/1:b..l P5637/1:b..l P6644/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=114873, q=1375 ncpus=1)
task:kworker/u8:14 state:R running task stack:23400 pid:6644 tgid:6644 ppid:2 task_flags:0x24248060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
preempt_schedule_notrace+0x56/0x90 kernel/sched/core.c:7556
preempt_schedule_notrace_thunk+0x16/0x30 arch/x86/entry/thunk.S:13
rcu_is_watching+0x81/0xb0 kernel/rcu/tree.c:754
trace_lock_acquire include/trace/events/lock.h:23 [inline]
lock_acquire+0x58/0x350 kernel/locking/lockdep.c:5905
rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
rcu_read_lock include/linux/rcupdate.h:849 [inline]
percpu_ref_put_many+0x3d/0x240 include/linux/percpu-refcount.h:331
percpu_ref_put include/linux/percpu-refcount.h:352 [inline]
blk_mq_dispatch_list+0xd31/0xe10 block/blk-mq.c:2935
blk_mq_flush_plug_list+0x45f/0x540 block/blk-mq.c:2979
__blk_flush_plug+0x3ed/0x4d0 block/blk-core.c:1270
blk_flush_plug include/linux/blk_plug.h:51 [inline]
io_schedule_prepare kernel/sched/core.c:8189 [inline]
io_schedule+0x77/0xd0 kernel/sched/core.c:8219
rq_qos_wait+0x266/0x360 block/blk-rq-qos.c:307
__wbt_wait block/blk-wbt.c:598 [inline]
wbt_wait+0x326/0x550 block/blk-wbt.c:658
__rq_qos_throttle+0x6b/0xb0 block/blk-rq-qos.c:66
rq_qos_throttle block/blk-rq-qos.h:164 [inline]
blk_mq_get_new_requests block/blk-mq.c:3045 [inline]
blk_mq_submit_bio+0x165d/0x2bb0 block/blk-mq.c:3181
__submit_bio_noacct_mq block/blk-core.c:756 [inline]
submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790
blk_crypto_submit_bio include/linux/blk-crypto.h:212 [inline]
ext4_io_submit+0x11b/0x190 fs/ext4/page-io.c:396
ext4_do_writepages+0xba4/0x4770 fs/ext4/inode.c:2888
ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3032
do_writepages+0x338/0x560 mm/page-writeback.c:2560
__writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1803
writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2114
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2190
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2301
wb_check_old_data_flush fs/fs-writeback.c:2405 [inline]
wb_do_writeback fs/fs-writeback.c:2484 [inline]
wb_workfn+0xc92/0x10f0 fs/fs-writeback.c:2512
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3560
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
task:syz-executor state:R running task stack:22344 pid:5637 tgid:5637 ppid:5617 task_flags:0x400140 flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
preempt_schedule_irq+0x4b/0x90 kernel/sched/core.c:7606
irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:539 [inline]
irqentry_exit+0x14f/0x920 kernel/entry/common.c:167
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:__asan_memset+0x22/0x50 mm/kasan/shadow.c:84
Code: 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 56 53 48 89 d3 89 f5 49 89 fe 48 8b 4c 24 18 48 89 d6 ba 01 00 00 00 e8 1e e5 ff ff <84> c0 74 11 4c 89 f7 89 ee 48 89 da 5b 41 5e 5d e9 49 56 af 09 31
RSP: 0018:ffffc90003987240 EFLAGS: 00000256
RAX: ffffc90003987401 RBX: 0000000000000010 RCX: ffffffff81781e54
RDX: 0000000000000001 RSI: 0000000000000010 RDI: ffffc90003987358
RBP: 0000000000000000 R08: ffffc90003987367 R09: 1ffff92000730e6c
R10: dffffc0000000000 R11: fffff52000730e6d R12: dffffc0000000000
R13: ffffffff9116fdcc R14: ffffc90003987358 R15: ffffc90003987350
unwind_next_frame+0xd04/0x2550 arch/x86/kernel/unwind_orc.c:621
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
save_stack+0x122/0x230 mm/page_owner.c:183
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:338
reset_page_owner include/linux/page_owner.h:26 [inline]
__free_pages_prepare mm/page_alloc.c:1418 [inline]
free_unref_folios+0xdc2/0x14e0 mm/page_alloc.c:3022
folios_put_refs+0x9e9/0xb30 mm/folio.c:1036
folio_batch_release include/linux/folio_batch.h:101 [inline]
shmem_undo_range+0x4e6/0x15d0 mm/shmem.c:1161
shmem_truncate_range mm/shmem.c:1289 [inline]
shmem_evict_inode+0x247/0xae0 mm/shmem.c:1420
evict+0x624/0xb50 fs/inode.c:822
filename_unlinkat+0x43f/0x610 fs/namei.c:5723
__do_sys_unlink fs/namei.c:5754 [inline]
__se_sys_unlink+0x2e/0x140 fs/namei.c:5751
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0cccd9d287
RSP: 002b:00007fffcf36d4a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0cccd9d287
RDX: 00007fffcf36d4d0 RSI: 00007fffcf36d560 RDI: 00007fffcf36d560
RBP: 00007fffcf36d560 R08: 00007fffcf36e560 R09: 00000000ffffffff
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fffcf36e5f0
R13: 00007f0ccce34d23 R14: 000000000006adda R15: 00007fffcf36e630
task:syz.6.1851 state:R running task stack:24648 pid:12394 tgid:12394 ppid:6716 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7463
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline]
_raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
zap_pte_range mm/memory.c:2095 [inline]
zap_pmd_range mm/memory.c:2151 [inline]
zap_pud_range mm/memory.c:2179 [inline]
zap_p4d_range mm/memory.c:2200 [inline]
__zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240
unmap_vmas+0x390/0x550 mm/memory.c:2309
exit_mmap+0x293/0x9f0 mm/mmap.c:1315
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:592
do_exit+0x6cd/0x2360 kernel/exit.c:974
do_group_exit+0x22d/0x2f0 kernel/exit.c:1129
get_signal+0x121b/0x12c0 kernel/signal.c:3112
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4862f9e199
RSP: 002b:00007ffc2c652398 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00007f4862f9e199
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f4863225fa8
RBP: 0000000000001d60 R08: 0000000000000020 R09: 0000000000000000
R10: 00007f4863225fa0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4863225fac R14: 00007f4863225fa8 R15: 00007f4863225fa0
task:syz.5.1839 state:R running task stack:26888 pid:12391 tgid:12363 ppid:5629 task_flags:0x40044c flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
preempt_schedule_common+0x7f/0xd0 kernel/sched/core.c:7463
preempt_schedule_thunk+0x16/0x40 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:201 [inline]
_raw_spin_unlock+0x41/0x50 kernel/locking/spinlock.c:213
spin_unlock include/linux/spinlock.h:401 [inline]
zap_pte_range mm/memory.c:2095 [inline]
zap_pmd_range mm/memory.c:2151 [inline]
zap_pud_range mm/memory.c:2179 [inline]
zap_p4d_range mm/memory.c:2200 [inline]
__zap_vma_range+0x40e1/0x4f80 mm/memory.c:2240
unmap_vmas+0x390/0x550 mm/memory.c:2309
exit_mmap+0x293/0x9f0 mm/mmap.c:1315
__mmput+0x118/0x420 kernel/fork.c:1193
exit_mm+0x18e/0x240 kernel/exit.c:592
do_exit+0x6cd/0x2360 kernel/exit.c:974
do_group_exit+0x22d/0x2f0 kernel/exit.c:1129
get_signal+0x121b/0x12c0 kernel/signal.c:3112
arch_do_signal_or_restart+0xbb/0x860 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:66 [inline]
exit_to_user_mode_loop+0x10e/0x770 kernel/entry/common.c:101
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline]
do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3d7bb9e199
RSP: 002b:00007f3d7c9eb0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f3d7be26188 RCX: 00007f3d7bb9e199
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3d7be26188
RBP: 00007f3d7be26180 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3d7be26218 R14: 00007ffce8dd4dc0 R15: 00007ffce8dd4ea8
rcu: rcu_preempt kthread starved for 7827 jiffies! g114873 f0x0 RCU_GP_WAIT_FQS(5) ->state=R ->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 tgid:17 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
schedule_timeout+0x152/0x2c0 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x30c/0x11f0 kernel/rcu/tree.c:2122
rcu_gp_kthread+0x9e/0x2b0 kernel/rcu/tree.c:2330
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
CPU: 0 UID: 0 PID: 3224 Comm: kworker/R-bat_e Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026
Workqueue: bat_events batadv_tt_purge
RIP: 0010:ipt_do_table+0x32d/0x15d0 net/ipv4/netfilter/ip_tables.c:-1
Code: 48 8b 44 24 60 48 8d 58 18 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 ee 19 c5 f7 48 8b 1b e8 a6 68 74 01 41 89 c6 <48> 89 5c 24 38 48 83 c3 38 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74
RSP: 0018:ffffc90000006f40 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88807b153000 RCX: 8000000000000301
RDX: 8000000000000100 RSI: ffffffff8c6dad60 RDI: ffffffff8c6dad20
RBP: ffffc90000007120 R08: 0000000000000100 R09: ffffc90000007080
R10: dffffc0000000000 R11: fffff52000000e14 R12: ffff888164198b00
R13: 0000000000000003 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888124cc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000023000 CR3: 00000000216aa000 CR4: 0000000000350ef0
Call Trace:
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook+0x22a/0x3a0 include/linux/netfilter.h:280
__ip_local_out+0x558/0x6a0 net/ipv4/ip_output.c:120
ip_local_out+0x2a/0x190 net/ipv4/ip_output.c:129
synproxy_send_client_synack+0x89b/0xde0 net/netfilter/nf_synproxy_core.c:487
nft_synproxy_eval_v4+0x362/0x4e0 net/netfilter/nft_synproxy.c:59
nft_synproxy_do_eval+0x389/0x5d0 net/netfilter/nft_synproxy.c:142
expr_call_ops_eval net/netfilter/nf_tables_core.c:232 [inline]
nft_do_chain+0x132b/0x1b10 net/netfilter/nf_tables_core.c:285
nft_do_chain_ipv4+0x195/0x290 net/netfilter/nft_chain_filter.c:24
nf_hook_entry_hookfn include/linux/netfilter.h:165 [inline]
nf_hook_slow+0xc5/0x220 net/netfilter/core.c:619
nf_hook include/linux/netfilter.h:280 [inline]
NF_HOOK+0x21f/0x3c0 include/linux/netfilter.h:323
NF_HOOK+0x336/0x3c0 include/linux/netfilter.h:325
__netif_receive_skb_one_core net/core/dev.c:6297 [inline]
__netif_receive_skb net/core/dev.c:6410 [inline]
process_backlog+0xa6b/0x18b0 net/core/dev.c:6761
__napi_poll+0xaa/0x330 net/core/dev.c:7830
napi_poll net/core/dev.c:7893 [inline]
net_rx_action+0x61d/0xf50 net/core/dev.c:8050
handle_softirqs+0x226/0x860 kernel/softirq.c:645
do_softirq+0x77/0xd0 kernel/softirq.c:546
__local_bh_enable_ip+0x100/0x140 kernel/softirq.c:473
spin_unlock_bh include/linux/spinlock.h:407 [inline]
batadv_tt_global_purge net/batman-adv/translation-table.c:2390 [inline]
batadv_tt_purge+0x4ae/0xa10 net/batman-adv/translation-table.c:3754
process_one_work kernel/workqueue.c:3396 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3479
rescuer_thread+0x7c5/0x10e0 kernel/workqueue.c:3703
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245