INFO: task syz-executor:15862 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:15862 tgid:15862 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x66d/0x6f0 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7fc9531909a3 RSP: 002b:00007ffeb83b42e8 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fc953ee4620 RCX: 00007fc9531909a3 RDX: 000000000000002c RSI: 00007fc953ee4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffeb83b4304 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fc953ee4670 R15: 0000000000000000 INFO: task syz-executor:15864 blocked for more than 123 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:15864 tgid:15864 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x66d/0x6f0 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f967c3909a3 RSP: 002b:00007ffe4a926458 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f967d0e4620 RCX: 00007f967c3909a3 RDX: 0000000000000028 RSI: 00007f967d0e4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffe4a926474 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f967d0e4670 R15: 0000000000000000 INFO: task syz-executor:15866 blocked for more than 127 seconds. Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:0 pid:15866 tgid:15866 ppid:1 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5945 [inline] __schedule+0x1322/0x1df0 kernel/sched/core.c:7791 __schedule_loop kernel/sched/core.c:7872 [inline] schedule+0xc6/0x240 kernel/sched/core.c:7887 schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7944 __mutex_lock_common kernel/locking/mutex.c:707 [inline] __mutex_lock+0x81e/0x1b50 kernel/locking/mutex.c:803 __mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134 mutex_lock+0x102/0x1c0 kernel/locking/mutex.c:285 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x75f/0xa00 net/core/rtnetlink.c:6675 netlink_rcv_skb+0x22b/0x4a0 net/netlink/af_netlink.c:2537 rtnetlink_rcv+0x20/0x30 net/core/rtnetlink.c:6696 netlink_unicast_kernel net/netlink/af_netlink.c:1316 [inline] netlink_unicast+0x8c9/0xa60 net/netlink/af_netlink.c:1342 netlink_sendmsg+0x7f0/0xaf0 net/netlink/af_netlink.c:1886 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x66d/0x6f0 net/socket.c:2217 __do_sys_sendto net/socket.c:2229 [inline] __se_sys_sendto net/socket.c:2225 [inline] __x64_sys_sendto+0xe9/0x100 net/socket.c:2225 x64_sys_call+0x2c2c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0xf0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f98c57909a3 RSP: 002b:00007ffc65955c78 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f98c64e4620 RCX: 00007f98c57909a3 RDX: 000000000000002c RSI: 00007f98c64e4670 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00007ffc65955c94 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f98c64e4670 R15: 0000000000000000 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x10c/0x190 lib/dump_stack.c:120 dump_stack+0x19/0x20 lib/dump_stack.c:129 nmi_cpu_backtrace+0x2bf/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline] watchdog+0xd8f/0xed0 kernel/hung_task.c:423 kthread+0x2ca/0x370 kernel/kthread.c:389 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 33 Comm: rcuop/1 Not tainted 6.12.38-syzkaller-gbf0fb8bb181b #0 d02c7cfa86e34ad1734bbfdc1f5f1c3ce9be47fc Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:update_stack_state+0x1/0x4b0 arch/x86/kernel/unwind_frame.c:198 Code: 90 90 90 90 90 90 90 90 90 55 48 89 e5 48 8b 07 5d c3 cc cc cc cc cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 81 ec 98 00 00 00 49 89 f7 RSP: 0018:ffffc900000074d8 EFLAGS: 00000246 RAX: ffffc90000227f48 RBX: ffffc90000007568 RCX: 0000000000007500 RDX: dffffc0000000000 RSI: ffffc90000227f48 RDI: ffffc90000007568 RBP: ffffc90000007558 R08: ffffc90000007630 R09: ffffc90000007628 R10: 0000000000000013 R11: ffffffff81742a80 R12: 0000000000000000 R13: 1ffff92000000eb8 R14: ffffc900000075c0 R15: ffffc90000227f18 FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe1247ffec CR3: 000000010b3e0000 CR4: 00000000003526b0 Call Trace: arch_stack_walk+0x139/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9d/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x4a/0x60 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2417 [inline] slab_free mm/slub.c:4666 [inline] kmem_cache_free+0x1c1/0x510 mm/slub.c:4773 kfree_skbmem net/core/skbuff.c:-1 [inline] __kfree_skb+0x18f/0x210 net/core/skbuff.c:1203 sk_skb_reason_drop+0xd8/0x310 net/core/skbuff.c:1240 kfree_skb_reason include/linux/skbuff.h:1271 [inline] kfree_skb include/linux/skbuff.h:1280 [inline] ip6_mc_input+0x4f3/0x670 net/ipv6/ip6_input.c:587 dst_input include/net/dst.h:469 [inline] ip6_rcv_finish+0x344/0x3c0 net/ipv6/ip6_input.c:79 NF_HOOK include/linux/netfilter.h:317 [inline] ipv6_rcv+0xed/0x220 net/ipv6/ip6_input.c:309 __netif_receive_skb_one_core net/core/dev.c:5757 [inline] __netif_receive_skb net/core/dev.c:5870 [inline] process_backlog+0x44b/0xae0 net/core/dev.c:6206 __napi_poll+0xd0/0x610 net/core/dev.c:6857 napi_poll net/core/dev.c:6926 [inline] net_rx_action+0x584/0xce0 net/core/dev.c:7048 handle_softirqs+0x1ab/0x630 kernel/softirq.c:621 __do_softirq+0xf/0x16 kernel/softirq.c:659 do_softirq+0xa6/0x100 kernel/softirq.c:503 __local_bh_enable_ip+0x74/0x80 kernel/softirq.c:430 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_do_batch+0x5c6/0xd20 kernel/rcu/tree.c:2594 nocb_cb_wait kernel/rcu/tree_nocb.h:923 [inline] rcu_nocb_cb_kthread+0x4dc/0xac0 kernel/rcu/tree_nocb.h:957