rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P9660/1:b..l rcu: (detected by 0, t=10502 jiffies, g=24509, q=684 ncpus=2) task:syz-executor state:R running task stack:20544 pid:9660 tgid:9660 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:cpumask_test_cpu include/linux/cpumask.h:570 [inline] RIP: 0010:cpu_online include/linux/cpumask.h:1117 [inline] RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0xb9/0x550 kernel/locking/lockdep.c:5820 Code: 44 2c 11 f3 f3 f3 f3 66 43 c7 44 2c 15 f3 f3 43 c6 44 2c 17 f3 0f 1f 44 00 00 65 8b 05 0c 2a 89 7e 83 f8 08 0f 83 f4 02 00 00 <89> c3 48 89 d8 48 c1 e8 06 48 8d 3c c5 30 46 19 90 be 08 00 00 00 RSP: 0018:ffffc900032ff300 EFLAGS: 00000297 RAX: 0000000000000001 RBX: ffffea0001aabb40 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e937aa0 RBP: ffffc900032ff448 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed1004916198 R12: 1ffff9200065fe68 R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] page_ext_get+0x3d/0x2a0 mm/page_ext.c:525 __page_table_check_zero+0xb1/0x350 mm/page_table_check.c:148 page_table_check_free include/linux/page_table_check.h:41 [inline] free_pages_prepare mm/page_alloc.c:1128 [inline] free_unref_page+0xe04/0x1130 mm/page_alloc.c:2657 discard_slab mm/slub.c:2673 [inline] __put_partials+0xeb/0x130 mm/slub.c:3142 put_cpu_partial+0x17c/0x250 mm/slub.c:3217 __slab_free+0x2ea/0x3d0 mm/slub.c:4468 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4283 [inline] __kmalloc_node_track_caller_noprof+0x28b/0x4c0 mm/slub.c:4302 __kmemdup_nul mm/util.c:61 [inline] kstrdup+0x39/0xb0 mm/util.c:81 __kernfs_new_node+0x9d/0x870 fs/kernfs/dir.c:620 kernfs_new_node+0x137/0x240 fs/kernfs/dir.c:700 __kernfs_create_file+0x49/0x2e0 fs/kernfs/file.c:1034 cgroup_add_file kernel/cgroup/cgroup.c:4251 [inline] cgroup_addrm_files+0xab8/0xe50 kernel/cgroup/cgroup.c:4305 css_populate_dir+0x120/0x3b0 kernel/cgroup/cgroup.c:1761 cgroup_apply_control_enable+0x621/0xaf0 kernel/cgroup/cgroup.c:3247 cgroup_mkdir+0xa83/0xd60 kernel/cgroup/cgroup.c:5847 kernfs_iop_mkdir+0x253/0x3f0 fs/kernfs/dir.c:1246 vfs_mkdir+0x2f9/0x4f0 fs/namei.c:4311 do_mkdirat+0x264/0x3a0 fs/namei.c:4334 __do_sys_mkdirat fs/namei.c:4349 [inline] __se_sys_mkdirat fs/namei.c:4347 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4347 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fcdb5d7e747 RSP: 002b:00007ffd24b13c48 EFLAGS: 00000206 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fcdb5df3f3f RCX: 00007fcdb5d7e747 RDX: 00000000000001ff RSI: 00007ffd24b13c90 RDI: 00000000ffffff9c RBP: 0000000000000001 R08: 0000000000000013 R09: 00007ffd24b13997 R10: 0000000000000000 R11: 0000000000000206 R12: 00007fcdb5df539e R13: 0000000000000003 R14: 00007ffd24b13c90 R15: 00007ffd24b13cd0 rcu: rcu_preempt kthread starved for 1535 jiffies! g24509 f0x0 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:26264 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: CPU: 0 UID: 0 PID: 1113 Comm: kworker/u8:7 Not tainted 6.13.0-rc1-syzkaller-00182-g0f6ede9fbc74 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg+0x33/0x210 arch/x86/kernel/unwind_orc.c:403 Code: 53 48 83 ec 20 48 89 54 24 18 49 89 f0 49 89 fe 48 ba 00 00 00 00 00 fc ff df 48 8d 6f 08 49 89 ec 49 c1 ec 03 41 80 3c 14 00 <48> 89 34 24 74 16 48 89 ef e8 5f 8b be 00 4c 8b 04 24 48 ba 00 00 RSP: 0018:ffffc90000006558 EFLAGS: 00000246 RAX: fffffffffffffff0 RBX: ffffffff9124135e RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffc90000007eb0 RDI: ffffc90000006680 RBP: ffffc90000006688 R08: ffffc90000007eb0 R09: 0000000000000000 R10: ffffc900000066d0 R11: fffff52000000cdc R12: 1ffff92000000cd1 R13: ffffc90000006680 R14: ffffc90000006680 R15: ffffc900000066d0 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1b9d293c43 CR3: 000000000e736000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x1799/0x22d0 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x118/0x1d0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2338 [inline] slab_free mm/slub.c:4598 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4700 skb_release_all net/core/skbuff.c:1188 [inline] __kfree_skb net/core/skbuff.c:1204 [inline] sk_skb_reason_drop+0x194/0x380 net/core/skbuff.c:1242 kfree_skb_reason include/linux/skbuff.h:1263 [inline] kfree_skb include/linux/skbuff.h:1272 [inline] ip6_mc_input+0xa1f/0xc30 net/ipv6/ip6_input.c:587 ip_sabotage_in+0x203/0x290 net/bridge/br_netfilter_hooks.c:1021 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_slow+0xc3/0x220 net/netfilter/core.c:626 nf_hook include/linux/netfilter.h:269 [inline] NF_HOOK+0x29e/0x450 include/linux/netfilter.h:312 __netif_receive_skb_one_core net/core/dev.c:5672 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5785 netif_receive_skb_internal net/core/dev.c:5871 [inline] netif_receive_skb+0x1e8/0x890 net/core/dev.c:5930 NF_HOOK+0x9e/0x400 include/linux/netfilter.h:314 br_handle_frame_finish+0x18ed/0x1fe0 br_nf_hook_thresh+0x472/0x590 br_nf_pre_routing_finish_ipv6+0xaa0/0xdd0 NF_HOOK include/linux/netfilter.h:314 [inline] br_nf_pre_routing_ipv6+0x379/0x770 net/bridge/br_netfilter_ipv6.c:184 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline] nf_hook_bridge_pre net/bridge/br_input.c:277 [inline] br_handle_frame+0x9fd/0x1530 net/bridge/br_input.c:424 __netif_receive_skb_core+0x14eb/0x4690 net/core/dev.c:5566 __netif_receive_skb_one_core net/core/dev.c:5670 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5785 process_backlog+0x662/0x15b0 net/core/dev.c:6117 __napi_poll+0xcb/0x490 net/core/dev.c:6883 napi_poll net/core/dev.c:6952 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7074 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x7c4/0xb50 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244