rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 1-...!: (3 ticks this GP) idle=c514/1/0x4000000000000000 softirq=20834/20834 fqs=0
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5914/1:b..l
rcu: (detected by 0, t=10502 jiffies, g=14585, q=2068 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3950 Comm: kworker/u8:12 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x70 kernel/kcov.c:216
Code: e9 2d 0f 5e 00 be 03 00 00 00 5b e9 e2 72 ed 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 34 24 <65> 48 8b 15 48 6c f3 11 65 8b 05 59 6c f3 11 a9 00 01 ff 00 74 1d
RSP: 0018:ffffc90000a08d18 EFLAGS: 00000002
RAX: 0000000080010001 RBX: ffff88807a366084 RCX: ffffffff897f8022
RDX: ffff8880332e0000 RSI: ffffffff897f8030 RDI: 0000000000000004
RBP: 0000000000000001 R08: 0000000000000004 R09: 0000000000000002
R10: 0000000000000001 R11: ffff8880332e0b30 R12: 0000000000000000
R13: ffff88807a366008 R14: 0000000000000002 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881249fb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c0089ec000 CR3: 0000000076bc2000 CR4: 00000000003526f0
Call Trace:
taprio_set_budgets+0x1f0/0x310 net/sched/sch_taprio.c:672
advance_sched+0x5f6/0xc80 net/sched/sch_taprio.c:983
__run_hrtimer kernel/time/hrtimer.c:1777 [inline]
__hrtimer_run_queues+0x202/0xc40 kernel/time/hrtimer.c:1841
hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1903
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1045 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x3c0 arch/x86/kernel/apic/apic.c:1062
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1056
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:write_comp_data+0x42/0x90 kernel/kcov.c:246
Code: a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 6c 16 00 00 85 c0 74 4f 8b 82 48 16 00 00 <83> f8 03 75 44 48 8b 82 50 16 00 00 8b 92 4c 16 00 00 48 8b 38 48
RSP: 0018:ffffc9000e0c6c20 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888031f25280 RCX: ffffffff8208ea09
RDX: ffff8880332e0000 RSI: 0000000000000133 RDI: 0000000000000006
RBP: 00000000000001ea R08: 0000000000000006 R09: 0000000000000133
R10: 00000000000001ea R11: ffff8880332e0b30 R12: dffffc0000000000
R13: 0000000000000133 R14: 0000000000000049 R15: 0000000000000133
vma_interval_tree_subtree_search+0xf9/0x1a0 mm/interval_tree.c:23
vma_interval_tree_iter_next+0x1f1/0x250 mm/interval_tree.c:23
__rmap_walk_file+0x3cb/0x620 mm/rmap.c:2917
rmap_walk_file+0x174/0x1f0 mm/rmap.c:2960
rmap_walk mm/rmap.c:2971 [inline]
folio_mkclean+0x251/0x3f0 mm/rmap.c:1097
folio_clear_dirty_for_io+0x153/0x6b0 mm/page-writeback.c:2932
mpage_submit_folio+0x84/0x2d0 fs/ext4/inode.c:2068
mpage_process_page_bufs+0x47c/0x8d0 fs/ext4/inode.c:2198
mpage_prepare_extent_to_map+0x750/0x1510 fs/ext4/inode.c:2737
ext4_do_writepages+0xa11/0x3c80 fs/ext4/inode.c:2878
ext4_writepages+0x37a/0x7d0 fs/ext4/inode.c:3026
do_writepages+0x27a/0x600 mm/page-writeback.c:2598
__writeback_single_inode+0x168/0x14a0 fs/fs-writeback.c:1737
writeback_sb_inodes+0x72e/0x1ce0 fs/fs-writeback.c:2030
__writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2107
wb_writeback+0x799/0xae0 fs/fs-writeback.c:2218
wb_check_old_data_flush fs/fs-writeback.c:2322 [inline]
wb_do_writeback fs/fs-writeback.c:2375 [inline]
wb_workfn+0x8a0/0xbb0 fs/fs-writeback.c:2403
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
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
task:kworker/1:5 state:R running task stack:27240 pid:5914 tgid:5914 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: events_power_efficient gc_worker
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_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:688
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline]
RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:342 [inline]
RIP: 0010:gc_worker+0x2d5/0x16e0 net/netfilter/nf_conntrack_core.c:1548
Code: 00 00 48 c7 c7 a8 2d 89 90 e8 a7 65 06 f8 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 95 51 2b f8 58 48 85 db 0f 85 d4 0f 00 00 b6 56 2b f8 8b 1d 90 a0 f5 06 41 89 dc 31 ff 41 83 e4 01 44 89
RSP: 0018:ffffc900036b7ad8 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff89939849
RDX: ffff88802fdac980 RSI: ffffffff89939858 RDI: 0000000000000007
RBP: ffffffff9b09d86c R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802fdad4b0 R12: ffff88814d600000
R13: 0000000000040000 R14: dffffc0000000000 R15: 0000000000001770
process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257
process_scheduled_works kernel/workqueue.c:3340 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421
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: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g14585 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: Possible timer handling issue on cpu=1 timer-softirq=7017
rcu: rcu_preempt kthread starved for 10502 jiffies! g14585 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:28440 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