rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 1, t=10502 jiffies, g=24657, q=1503 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4294961726-4294951224), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10502 jiffies! g24657 f0x2 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:0 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00000010 Call trace: __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:775 (T) context_switch kernel/sched/core.c:5510 [inline] __schedule+0x1370/0x2d80 kernel/sched/core.c:7234 __schedule_loop kernel/sched/core.c:7311 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7326 schedule_timeout+0x13c/0x28c kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x284/0x13c4 kernel/rcu/tree.c:2123 rcu_gp_kthread+0x148/0x230 kernel/rcu/tree.c:2325 kthread+0x304/0x3d4 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: watchdog: BUG: soft lockup - CPU#0 stuck for 114s! [syz.7.1916:11302] Modules linked in: irq event stamp: 162 hardirqs last enabled at (161): [] kasan_quarantine_put+0xb4/0x1c4 mm/kasan/quarantine.c:234 hardirqs last disabled at (162): [] seqcount_lockdep_reader_access+0x40/0xf8 include/linux/seqlock.h:72 softirqs last enabled at (24): [] local_bh_enable include/linux/bottom_half.h:33 [inline] softirqs last enabled at (24): [] put_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:251 [inline] softirqs last enabled at (24): [] do_sve_acc+0x32c/0x4b8 arch/arm64/kernel/fpsimd.c:1349 softirqs last disabled at (22): [] local_bh_disable include/linux/bottom_half.h:20 [inline] softirqs last disabled at (22): [] get_cpu_fpsimd_context arch/arm64/kernel/fpsimd.c:234 [inline] softirqs last disabled at (22): [] do_sve_acc+0x10c/0x4b8 arch/arm64/kernel/fpsimd.c:1325 CPU: 0 UID: 0 PID: 11302 Comm: syz.7.1916 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 pstate: 83400005 (Nzcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : seqcount_lockdep_reader_access+0xd8/0xf8 include/linux/seqlock.h:76 lr : seqcount_lockdep_reader_access+0xd4/0xf8 include/linux/seqlock.h:75 sp : ffff800092586f00 x29: ffff800092586f00 x28: 1fffe00019d494b3 x27: 1ffff000124b0dfc x26: 1ffff000124b0dfd x25: dfff800000000000 x24: ffff7000124b0df8 x23: ffff80008e7cd130 x22: ffff800088a9e2c0 x21: 0000000000000000 x20: ffff80008055e9cc x19: 00000000000000c0 x18: 00000000ffffffff x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000001 x12: ffff0000f8c1d7c0 x11: ffff800080156ee8 x10: ffff8000885f22e6 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 00000000184897f0 x5 : ffff8000925864f8 x4 : 0000000000000008 x3 : ffff8000805585f8 x2 : 0000000000000080 x1 : ffff0000f8c1d7c0 x0 : 0000000000000000 Call trace: __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline] (P) arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline] (P) seqcount_lockdep_reader_access+0xd8/0xf8 include/linux/seqlock.h:75 (P) ktime_get_coarse_real_ts64_mg+0x74/0x1e0 kernel/time/timekeeping.c:2687 inode_set_ctime_current+0xa8/0xe1c fs/inode.c:2895 __simple_unlink+0x50/0xe4 fs/libfs.c:792 simple_unlink+0x28/0x44 fs/libfs.c:807 shmem_unlink+0x124/0x1bc mm/shmem.c:3917 shmem_rmdir+0x7c/0xa0 mm/shmem.c:3936 vfs_rmdir+0x354/0x590 fs/namei.c:5381 ovl_do_rmdir fs/overlayfs/overlayfs.h:215 [inline] ovl_workdir_cleanup+0x1bc/0x74c fs/overlayfs/readdir.c:1242 ovl_workdir_create+0x248/0x6a4 fs/overlayfs/super.c:337 ovl_make_workdir fs/overlayfs/super.c:678 [inline] ovl_get_workdir+0x290/0x133c fs/overlayfs/super.c:836 ovl_fill_super_creds fs/overlayfs/super.c:1449 [inline] ovl_fill_super+0x1fc0/0x31e0 fs/overlayfs/super.c:1560 vfs_get_super+0xb8/0x148 fs/super.c:1267 get_tree_nodev+0x2c/0x3c fs/super.c:1286 ovl_get_tree+0x28/0x38 fs/overlayfs/params.c:730 vfs_get_tree+0x90/0x28c fs/super.c:1694 fc_mount+0x24/0xac fs/namespace.c:1198 do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x2a4/0x538 fs/namespace.c:3841 path_mount+0x5f0/0xa88 fs/namespace.c:4161 do_mount+0xe8/0x148 fs/namespace.c:4174 __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount fs/namespace.c:4367 [inline] __arm64_sys_mount+0x334/0x380 fs/namespace.c:4367 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 11302 Comm: syz.7.1916 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 pstate: 23400005 (nzCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:-1 [inline] pc : arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] pc : handle_softirqs+0x1cc/0xd98 kernel/softirq.c:606 lr : handle_softirqs+0x1c8/0xd98 kernel/softirq.c:606 sp : ffff80008eae7ef0 x29: ffff80008eae7f80 x28: ffff0000f8c1d7c8 x27: ffff0000f8c1d7d0 x26: 1ffff000124b0dfd x25: 0000000000000382 x24: dfff800000000000 x23: ffff0001ade86640 x22: ffff0000f8c1d7c0 x21: 000000000000000a x20: ffff800088a85640 x19: ffff0001ade86640 x18: 00000000ffffffff x17: ffff800125401000 x16: ffff80008eae0000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000 x11: ffff800080156ee8 x10: ffff8000885f22e6 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : ffff80008199bca4 x5 : 0000000000000000 x4 : 0000000000000008 x3 : ffff800080156f90 x2 : 0000000000000000 x1 : ffff0000f8c1d7c0 x0 : ffff80008030e478 Call trace: __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P) arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P) handle_softirqs+0x1cc/0xd98 kernel/softirq.c:606 (P) __do_softirq+0x14/0x20 kernel/softirq.c:656 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:78 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:889 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:83 invoke_softirq kernel/softirq.c:503 [inline] __irq_exit_rcu+0x1ac/0x428 kernel/softirq.c:735 irq_exit_rcu+0x14/0x84 kernel/softirq.c:752 __el1_irq arch/arm64/kernel/entry-common.c:510 [inline] el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:522 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:527 el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:590 __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline] (P) arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline] (P) seqcount_lockdep_reader_access+0xd8/0xf8 include/linux/seqlock.h:75 (P) ktime_get_coarse_real_ts64_mg+0x74/0x1e0 kernel/time/timekeeping.c:2687 inode_set_ctime_current+0xa8/0xe1c fs/inode.c:2895 __simple_unlink+0x50/0xe4 fs/libfs.c:792 simple_unlink+0x28/0x44 fs/libfs.c:807 shmem_unlink+0x124/0x1bc mm/shmem.c:3917 shmem_rmdir+0x7c/0xa0 mm/shmem.c:3936 vfs_rmdir+0x354/0x590 fs/namei.c:5381 ovl_do_rmdir fs/overlayfs/overlayfs.h:215 [inline] ovl_workdir_cleanup+0x1bc/0x74c fs/overlayfs/readdir.c:1242 ovl_workdir_create+0x248/0x6a4 fs/overlayfs/super.c:337 ovl_make_workdir fs/overlayfs/super.c:678 [inline] ovl_get_workdir+0x290/0x133c fs/overlayfs/super.c:836 ovl_fill_super_creds fs/overlayfs/super.c:1449 [inline] ovl_fill_super+0x1fc0/0x31e0 fs/overlayfs/super.c:1560 vfs_get_super+0xb8/0x148 fs/super.c:1267 get_tree_nodev+0x2c/0x3c fs/super.c:1286 ovl_get_tree+0x28/0x38 fs/overlayfs/params.c:730 vfs_get_tree+0x90/0x28c fs/super.c:1694 fc_mount+0x24/0xac fs/namespace.c:1198 do_new_mount_fc fs/namespace.c:3765 [inline] do_new_mount+0x2a4/0x538 fs/namespace.c:3841 path_mount+0x5f0/0xa88 fs/namespace.c:4161 do_mount+0xe8/0x148 fs/namespace.c:4174 __do_sys_mount fs/namespace.c:4390 [inline] __se_sys_mount fs/namespace.c:4367 [inline] __arm64_sys_mount+0x334/0x380 fs/namespace.c:4367 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 104s! Showing busy workqueues and worker pools: workqueue events: flags=0x100 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=14 refcnt=15 pending: 6*nsim_dev_hwstats_traffic_work, 4*psi_avgs_work, 2*ovs_dp_masks_rebalance, debugfs_reap_work, vmstat_shepherd workqueue events_long: flags=0x100 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: defense_work_handler workqueue events_unbound: flags=0x2 pwq 8: cpus=0-1 flags=0x4 nice=0 active=13 refcnt=14 in-flight: 8591:toggle_allocation_gate for 105s pending: 9*nsim_dev_trap_report_work, cfg80211_wiphy_work, crng_reseed, cfg80211_wiphy_work pwq 8: cpus=0-1 flags=0x4 nice=0 active=15 refcnt=16 pending: 2*cfg80211_wiphy_work, linkwatch_event, flush_memcg_stats_dwork, 5*macvlan_process_broadcast, cfg80211_wiphy_work, macvlan_process_broadcast, cfg80211_wiphy_work, 3*macvlan_process_broadcast workqueue events_power_efficient: flags=0x82 pwq 8: cpus=0-1 flags=0x4 nice=0 active=7 refcnt=8 pending: gc_worker, reg_check_chans_work, hash_net4_gc, wg_ratelimiter_gc_entries, hash_netport4_gc, 2*neigh_managed_work pwq 8: cpus=0-1 flags=0x4 nice=0 active=9 refcnt=10 pending: 2*nf_flow_offload_work_gc, 2*neigh_periodic_work, hash_ipport6_gc, device_uncache_fw_images_work, do_cache_clean, 2*check_lifetime workqueue netns: flags=0x6000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=4 pending: cleanup_net workqueue mm_percpu_wq: flags=0x108 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=4 pending: lru_add_drain_per_cpu BAR(36), vmstat_update workqueue writeback: flags=0x4a pwq 8: cpus=0-1 flags=0x4 nice=0 active=3 refcnt=4 pending: 3*wb_workfn pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wb_workfn workqueue kblockd: flags=0x118 pwq 3: cpus=0 node=0 flags=0x0 nice=-20 active=4 refcnt=5 pending: 4*blk_mq_timeout_work workqueue ipv6_addrconf: flags=0x6000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=5 pending: addrconf_verify_work inactive: addrconf_verify_work workqueue krxrpcd: flags=0x2001a pwq 9: cpus=0-1 node=0 flags=0x4 nice=-20 active=1 refcnt=7 pending: rxrpc_peer_keepalive_worker inactive: 3*rxrpc_peer_keepalive_worker workqueue bat_events: flags=0x6000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=51 pending: batadv_bla_periodic_work inactive: 2*batadv_tt_purge, 2*batadv_purge_orig, 3*batadv_iv_send_outstanding_bat_ogm_packet, 6*batadv_mcast_mla_update, 4*batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, 9*batadv_iv_send_outstanding_bat_ogm_packet, batadv_tt_purge, 2*batadv_purge_orig, batadv_iv_send_outstanding_bat_ogm_packet, batadv_purge_orig, batadv_iv_send_outstanding_bat_ogm_packet, batadv_tt_purge, batadv_bla_periodic_work, 2*batadv_dat_purge, 2*batadv_tt_purge, batadv_dat_purge, 2*batadv_bla_periodic_work, batadv_dat_purge, batadv_bla_periodic_work, 2*batadv_dat_purge, batadv_bla_periodic_work workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=2 refcnt=3 pending: 2*wg_packet_handshake_send_worker workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg1: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-kex-wg1: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=2 refcnt=3 pending: 2*wg_packet_handshake_send_worker workqueue bond1: flags=0x2000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=5 pending: bond_mii_monitor inactive: bond_alb_monitor workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=2 refcnt=3 pending: wg_packet_encrypt_worker, wg_packet_tx_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue hci3: flags=0x20012 pwq 9: cpus=0-1 node=0 flags=0x4 nice=-20 active=1 refcnt=4 pending: hci_conn_timeout workqueue wg-kex-wg0: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg0: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-crypt-wg1: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_encrypt_worker, wg_packet_tx_worker, wg_packet_decrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue wg-kex-wg2: flags=0x6 pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=2 pending: wg_packet_handshake_send_worker workqueue wg-crypt-wg2: flags=0x128 pwq 2: cpus=0 node=0 flags=0x0 nice=0 active=3 refcnt=4 pending: wg_packet_decrypt_worker, wg_packet_tx_worker, wg_packet_encrypt_worker pwq 6: cpus=1 node=0 flags=0x0 nice=0 active=1 refcnt=2 pending: wg_packet_encrypt_worker workqueue bond2: flags=0x2000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=5 pending: bond_mii_monitor inactive: bond_alb_monitor workqueue bond2: flags=0x2000a pwq 8: cpus=0-1 flags=0x4 nice=0 active=1 refcnt=5 pending: bond_mii_monitor inactive: bond_3ad_state_machine_handler pool 8: cpus=0-1 flags=0x4 nice=0 hung=104s workers=22 idle: 8152 7428 8593 8147 5221 5222 7445 1121 3655 745 8153 7178 4858 39 8154 8592 7433 8155 15 40 12 Showing backtraces of busy workers in stalled worker pools: IPVS: ovf: UDP 224.0.0.2:0 - no destination available IPVS: ovf: UDP 224.0.0.2:0 - no destination available net_ratelimit: 7 callbacks suppressed GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog IPVS: ovf: UDP 224.0.0.2:0 - no destination available