rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P1090/2:b..l rcu: (detected by 0, t=10503 jiffies, g=45397, q=569 ncpus=2) task:kworker/u8:5 state:R running task stack:24224 pid:1090 tgid:1090 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-8:0) Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7078 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire.part.0+0x155/0x380 kernel/locking/lockdep.c:5814 Code: b8 ff ff ff ff 65 0f c1 05 40 b0 8b 7e 83 f8 01 0f 85 d0 01 00 00 9c 58 f6 c4 02 0f 85 e5 01 00 00 48 85 ed 0f 85 b6 01 00 00 <48> b8 00 00 00 00 00 fc ff df 48 01 c3 48 c7 03 00 00 00 00 48 c7 RSP: 0018:ffffc90003c66d10 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 1ffff9200078cda3 RCX: 0000000006809e84 RDX: 0000000000000001 RSI: ffffffff8b6cdce0 RDI: ffffffff8bd1ef20 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff2dca798 R10: ffffffff96e53cc7 R11: 0000000000000005 R12: 0000000000000000 R13: ffffffff8e1bb900 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ref_add_unless.constprop.0+0x36/0x390 include/linux/page_ref.h:235 folio_ref_add_unless include/linux/page_ref.h:248 [inline] folio_try_get include/linux/page_ref.h:264 [inline] find_get_entry mm/filemap.c:1996 [inline] filemap_get_folios_tag+0x1d6/0xad0 mm/filemap.c:2251 mpage_prepare_extent_to_map+0x3d6/0x1470 fs/ext4/inode.c:2448 ext4_do_writepages+0x968/0x32d0 fs/ext4/inode.c:2688 ext4_writepages+0x303/0x730 fs/ext4/inode.c:2824 do_writepages+0x1b3/0x820 mm/page-writeback.c:2708 __writeback_single_inode+0x166/0xfa0 fs/fs-writeback.c:1680 writeback_sb_inodes+0x606/0xfa0 fs/fs-writeback.c:1976 __writeback_inodes_wb+0xff/0x2e0 fs/fs-writeback.c:2047 wb_writeback+0x803/0xb80 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+0x8c0/0xbc0 fs/fs-writeback.c:2343 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread starved for 2388 jiffies! g45397 f0x0 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:27488 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2045 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2247 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 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: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc7-syzkaller-00019-gc45323b7560e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__kasan_check_read+0x8/0x20 mm/kasan/shadow.c:31 Code: 60 48 c7 c7 90 88 7c 8d 5b 5d 41 5c e9 01 85 7c ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 0c 24 <89> f6 31 d2 e9 1f f1 ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f RSP: 0018:ffffc900001e78e0 EFLAGS: 00000002 RAX: 0000000000000020 RBX: 0000000000000816 RCX: ffffffff8175e32e RDX: 1ffff11003add160 RSI: 0000000000000008 RDI: ffffffff96e53dc0 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000b92 R12: 0000000000000000 R13: ffff88801d6e8000 R14: 0000000000000816 R15: ffff88801d6e8ae0 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faaadb452d8 CR3: 000000007a12c000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class+0x4e/0x130 kernel/locking/lockdep.c:228 check_wait_context kernel/locking/lockdep.c:4850 [inline] __lock_acquire+0x410/0x3c40 kernel/locking/lockdep.c:5176 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] process_backlog+0x5a6/0x15f0 net/core/dev.c:6156 __napi_poll.constprop.0+0xb7/0x550 net/core/dev.c:6902 napi_poll net/core/dev.c:6971 [inline] net_rx_action+0xa94/0x1010 net/core/dev.c:7093 handle_softirqs+0x213/0x8f0 kernel/softirq.c:561 run_ksoftirqd kernel/softirq.c:950 [inline] run_ksoftirqd+0x3a/0x60 kernel/softirq.c:942 smpboot_thread_fn+0x661/0xa30 kernel/smpboot.c:164 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 net_ratelimit: 30130 callbacks suppressed bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) net_ratelimit: 32715 callbacks suppressed bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on veth0_to_bridge with own address as source address (addr:ee:69:83:de:2c:5c, vlan:0)