rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: (detected by 0, t=10985 jiffies, g=20469, q=1467 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10985 (4294964696-4294953711), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10985 jiffies! g20469 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:27128 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2054
rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2256
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 49 Comm: kworker/u8:3 Not tainted 6.16.0-rc3-syzkaller-g223e2288f4b8 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: writeback wb_workfn (flush-8:0)
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:473 [inline]
RIP: 0010:lock_release+0x27a/0x3e0 kernel/locking/lockdep.c:5894
Code: d8 45 85 ed 41 89 c5 7f d0 4c 89 ff 4c 89 f6 48 8b 54 24 18 e8 57 30 00 00 48 8b 5c 24 08 48 c7 c7 d6 ef b6 8d e8 e6 9d c8 09 ff ff ff ff 65 0f c1 05 19 0b ff 10 83 f8 01 75 51 48 c7 44 24
RSP: 0018:ffffc90000a08bf8 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 0e8f8215e167fd00
RDX: 0000000000000008 RSI: ffffffff8db6efd6 RDI: ffffffff8be28d40
RBP: ffff88801dabc830 R08: ffff88802f209887 R09: 1ffff11005e41310
R10: dffffc0000000000 R11: ffffed1005e41311 R12: 0000000000000008
R13: 0000000000000008 R14: ffff88807fcc6300 R15: ffff88801dabbc00
FS: 0000000000000000(0000) GS:ffff888125d50000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0f982eeff8 CR3: 0000000011b12000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
_raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
advance_sched+0x99f/0xc90 net/sched/sch_taprio.c:981
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x529/0xc60 kernel/time/hrtimer.c:1825
hrtimer_interrupt+0x45b/0xaa0 kernel/time/hrtimer.c:1887
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline]
__sysvec_apic_timer_interrupt+0x10b/0x410 arch/x86/kernel/apic/apic.c:1056
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:csd_lock_wait kernel/smp.c:340 [inline]
RIP: 0010:smp_call_function_many_cond+0xf69/0x12d0 kernel/smp.c:885
Code: 00 45 8b 2f 44 89 ee 83 e6 01 31 ff e8 c0 79 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6b 75 0b 00 eb 37 f3 90 <43> 0f b6 04 2c 84 c0 75 10 41 f7 07 01 00 00 00 74 1e e8 50 75 0b
RSP: 0018:ffffc90000b963e0 EFLAGS: 00000293
RAX: ffffffff81b4d920 RBX: ffff8880b873b1c0 RCX: ffff88801dabbc00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000b96540 R08: ffffffff8fa10cf7 R09: 1ffffffff1f4219e
R10: dffffc0000000000 R11: ffffffff81702110 R12: 1ffff110170c8385
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8880b8641c28
on_each_cpu_cond_mask+0x3f/0x80 kernel/smp.c:1052
__flush_tlb_multi arch/x86/include/asm/paravirt.h:91 [inline]
flush_tlb_multi arch/x86/mm/tlb.c:1361 [inline]
flush_tlb_mm_range+0x6b1/0x12c0 arch/x86/mm/tlb.c:1451
flush_tlb_page arch/x86/include/asm/tlbflush.h:324 [inline]
ptep_clear_flush+0x120/0x170 mm/pgtable-generic.c:101
page_vma_mkclean_one+0x406/0x740 mm/rmap.c:1059
page_mkclean_one+0x1c0/0x280 mm/rmap.c:1100
__rmap_walk_file+0x464/0x620 mm/rmap.c:2897
rmap_walk mm/rmap.c:2941 [inline]
folio_mkclean+0x297/0x390 mm/rmap.c:1132
folio_clear_dirty_for_io+0x1fa/0x8c0 mm/page-writeback.c:2964
mpage_submit_folio+0x84/0x3f0 fs/ext4/inode.c:2038
mpage_map_and_submit_buffers fs/ext4/inode.c:2303 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2439 [inline]
ext4_do_writepages+0x1df6/0x3f30 fs/ext4/inode.c:2863
ext4_writepages+0x205/0x350 fs/ext4/inode.c:2953
do_writepages+0x32e/0x550 mm/page-writeback.c:2636
__writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x6b5/0x1000 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245