rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P14290/1:b..l P14294/1:b..l rcu: (detected by 0, t=10503 jiffies, g=75297, q=860 ncpus=2) task:syz-executor state:R running task stack:28456 pid:14294 tgid:14294 ppid:11597 task_flags:0x400040 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7109 irqentry_exit+0x6f/0x90 kernel/entry/common.c:307 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x175/0x360 kernel/locking/lockdep.c:5875 Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 9b 13 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e RSP: 0018:ffffc9000402f738 EFLAGS: 00000206 RAX: cdaf879787345e00 RBX: 0000000000000000 RCX: cdaf879787345e00 RDX: 0000000000000000 RSI: ffffffff8db869c3 RDI: ffffffff8be29d80 RBP: ffffffff8172aae5 R08: 0000000000000000 R09: ffffffff8172aae5 R10: dffffc0000000000 R11: ffffffff81ad00a0 R12: 0000000000000002 R13: ffffffff8e13f0e0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf5/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 __slab_free+0x326/0x400 mm/slub.c:4554 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:385 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4347 kmemdup_noprof+0x2b/0x70 mm/util.c:137 kmemdup_noprof include/linux/fortify-string.h:765 [inline] shmem_symlink+0x1ab/0x510 mm/shmem.c:4113 vfs_symlink+0x143/0x2f0 fs/namei.c:4739 do_symlinkat+0x1b1/0x3f0 fs/namei.c:4765 __do_sys_symlinkat fs/namei.c:4781 [inline] __se_sys_symlinkat fs/namei.c:4778 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4778 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2b4c98dea7 RSP: 002b:00007fffde6c3698 EFLAGS: 00000202 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2b4c98dea7 RDX: 00007f2b4ca12390 RSI: 00000000ffffff9c RDI: 00007fffde6c3730 RBP: 00007fffde6c36dc R08: 0000000000000017 R09: 00007fffde6c33e7 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000007a R13: 000055555ba57590 R14: 00000000001261e1 R15: 00007fffde6c3730 task:syz.3.2156 state:R running task stack:26024 pid:14290 tgid:14285 ppid:11585 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6786 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6966 preempt_schedule+0xae/0xc0 kernel/sched/core.c:6990 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __local_bh_enable_ip+0x13e/0x1c0 kernel/softirq.c:414 local_bh_enable include/linux/bottom_half.h:33 [inline] ipt_do_table+0x13dd/0x1640 net/ipv4/netfilter/ip_tables.c:357 nf_hook_entry_hookfn include/linux/netfilter.h:157 [inline] nf_hook_slow+0xc5/0x220 net/netfilter/core.c:623 nf_hook+0x217/0x380 include/linux/netfilter.h:272 NF_HOOK_COND include/linux/netfilter.h:305 [inline] ip_output+0x16c/0x220 net/ipv4/ip_output.c:433 ip_local_out net/ipv4/ip_output.c:129 [inline] ip_send_skb net/ipv4/ip_output.c:1502 [inline] ip_push_pending_frames+0xbe/0x150 net/ipv4/ip_output.c:1522 raw_sendmsg+0x143f/0x18b0 net/ipv4/raw.c:657 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x19c/0x270 net/socket.c:727 ____sys_sendmsg+0x52d/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmmsg+0x227/0x430 net/socket.c:2709 __do_sys_sendmmsg net/socket.c:2736 [inline] __se_sys_sendmmsg net/socket.c:2733 [inline] __x64_sys_sendmmsg+0xa0/0xc0 net/socket.c:2733 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc3a178e929 RSP: 002b:00007fc3a2615038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fc3a19b6160 RCX: 00007fc3a178e929 RDX: 0000000004000095 RSI: 0000200000005240 RDI: 0000000000000007 RBP: 00007fc3a1810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc3a19b6160 R15: 00007ffed5422618