rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P19356/1:b..l rcu: (detected by 0, t=10502 jiffies, g=129213, q=464 ncpus=2) task:syz.6.2232 state:R running task stack:21456 pid:19356 tgid:19356 ppid:18993 task_flags:0x40044c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6943 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6967 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] zap_pte_range mm/memory.c:1761 [inline] zap_pmd_range mm/memory.c:1823 [inline] zap_pud_range mm/memory.c:1852 [inline] zap_p4d_range mm/memory.c:1873 [inline] unmap_page_range+0x3d52/0x48d0 mm/memory.c:1894 unmap_vmas+0x3cc/0x5f0 mm/memory.c:1984 exit_mmap+0x283/0xd40 mm/mmap.c:1284 __mmput+0x115/0x420 kernel/fork.c:1356 exit_mm+0x220/0x310 kernel/exit.c:570 do_exit+0x9ad/0x28e0 kernel/exit.c:925 do_group_exit+0x207/0x2c0 kernel/exit.c:1087 get_signal+0x16b2/0x1750 kernel/signal.c:3036 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f323c58cea7 RSP: 002b:00007f323c8cf9c8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: 0000000000000000 RBX: 00007f323d3456c0 RCX: 00007f323c58cea7 RDX: 0000000000000003 RSI: 0000000000020000 RDI: 00007f323d326000 RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000021000 R11: 0000000000000206 R12: 00007f323c8cfb20 R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 4915 jiffies! g129213 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:25752 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2024 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2226 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 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: 5210 Comm: udevd Not tainted 6.14.0-rc1-syzkaller-00034-g92514ef226f5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:preempt_count_sub+0x0/0x170 kernel/sched/core.c:5878 Code: 8c 77 ff ff ff 48 c7 c7 14 84 1b 90 e8 09 69 98 00 e9 66 ff ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 41 56 53 89 fb 48 c7 c0 80 09 40 9a 48 c1 e8 03 49 be RSP: 0018:ffffc90000006508 EFLAGS: 00000202 RAX: ffffc90000008000 RBX: ffffc900000065f0 RCX: ffffc90000006768 RDX: dffffc0000000000 RSI: ffffc90000000000 RDI: 0000000000000001 RBP: ffffc900000065e0 R08: ffffc90000006750 R09: 0000000000000000 R10: ffffc90000006630 R11: fffff52000000cc8 R12: dffffc0000000000 R13: ffffc900000065e0 R14: ffffc90000000000 R15: ffffc90000006760 FS: 00007f07d58d3c80(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f83ba1de095 CR3: 0000000031b4a000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x18e6/0x22d0 arch/x86/kernel/unwind_orc.c:672 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:576 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:2353 [inline] slab_free mm/slub.c:4609 [inline] kmem_cache_free+0x195/0x410 mm/slub.c:4711 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:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] ip6_mc_input+0xa1f/0xc30 net/ipv6/ip6_input.c:587 ip_sabotage_in+0x203/0x290 net/bridge/br_netfilter_hooks.c:993 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:5828 [inline] __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5941 netif_receive_skb_internal net/core/dev.c:6027 [inline] netif_receive_skb+0x1e8/0x890 net/core/dev.c:6086 NF_HOOK+0x9e/0x400 include/linux/netfilter.h:314 br_handle_frame_finish+0x1905/0x2000 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:282 [inline] br_handle_frame+0x9f3/0x1530 net/bridge/br_input.c:433 __netif_receive_skb_core+0x13e7/0x4540 net/core/dev.c:5722 __netif_receive_skb_one_core net/core/dev.c:5826 [inline] __netif_receive_skb+0x12f/0x650 net/core/dev.c:5941 process_backlog+0x662/0x15b0 net/core/dev.c:6289 __napi_poll+0xcb/0x490 net/core/dev.c:7106 napi_poll net/core/dev.c:7175 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:7297 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561 __do_softirq kernel/softirq.c:595 [inline] invoke_softirq kernel/softirq.c:435 [inline] __irq_exit_rcu+0xf7/0x220 kernel/softirq.c:662 irq_exit_rcu+0x9/0x30 kernel/softirq.c:678 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:pfn_to_bitidx mm/page_alloc.c:348 [inline] RIP: 0010:get_pfnblock_flags_mask mm/page_alloc.c:367 [inline] RIP: 0010:get_pfnblock_migratetype mm/page_alloc.c:382 [inline] RIP: 0010:free_frozen_pages+0x65c/0x10e0 mm/page_alloc.c:2671 Code: 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 de 5f 0e 00 4c 69 ed 40 07 00 00 48 8b 03 <4c> 89 f5 48 c1 ed 07 4c 89 f1 48 c1 e9 0a 83 e1 18 48 8d 5c 08 18 RSP: 0018:ffffc900031276d8 EFLAGS: 00000202 RAX: ffff88813fffa0a0 RBX: ffff88813fffa6c8 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 00000000000000ff RDI: ffffed100c5dd000 RBP: 0000000000000001 R08: dffffc0000000000 R09: 0000000000000000 R10: ffffed100c5dc000 R11: fffffbfff285f30f R12: 1ffffd4000317700 R13: 0000000000000740 R14: 0000000000062ee0 R15: ffff88813fffb540 __slab_free+0x2c2/0x380 mm/slub.c:4520 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:4294 [inline] __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4306 kmalloc_noprof include/linux/slab.h:905 [inline] tomoyo_realpath_from_path+0xcf/0x5e0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x2b7/0x740 security/tomoyo/file.c:822 security_inode_getattr+0x130/0x330 security/security.c:2377 vfs_getattr+0x2a/0x3a0 fs/stat.c:243 vfs_statx_path fs/stat.c:283 [inline] vfs_statx+0x18c/0x490 fs/stat.c:347 vfs_fstatat+0xe5/0x130 fs/stat.c:366 __do_sys_newfstatat fs/stat.c:530 [inline] __se_sys_newfstatat fs/stat.c:524 [inline] __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:524 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: 0033:0x7f07d55165f4 Code: 64 c7 00 09 00 00 00 83 c8 ff c3 48 89 f2 b9 00 01 00 00 48 89 fe bf 9c ff ff ff e9 00 00 00 00 41 89 ca b8 06 01 00 00 0f 05 <45> 31 c0 3d 00 f0 ff ff 76 10 48 8b 15 03 a8 0d 00 f7 d8 41 83 c8 RSP: 002b:00007ffc75c03168 EFLAGS: 00000246 ORIG_RAX: 0000000000000106 RAX: ffffffffffffffda RBX: 0000556b05eeb6d0 RCX: 00007f07d55165f4 RDX: 00007ffc75c03178 RSI: 0000556b05ed97ff RDI: 00000000ffffff9c RBP: 0000556b3eb95448 R08: 00062305ed946d00 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00062305ed946d00 R15: 0000556b05edfdca net_ratelimit: 16024 callbacks suppressed 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:aa:aa:aa:aa:aa:0c, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, 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 bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:0c, vlan:0) bridge0: received packet on bridge_slave_0 with own address as source address (addr:aa:aa:aa:aa:aa:1b, vlan:0)