INFO: task syz.0.94:6704 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.94 state:D stack:28776 pid:6704 tgid:6657 ppid:5816 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:867 [inline]
open_last_lookups fs/namei.c:3797 [inline]
path_openat+0x8da/0x3830 fs/namei.c:4036
do_filp_open+0x1fa/0x410 fs/namei.c:4066
do_sys_openat2+0x121/0x1c0 fs/open.c:1429
do_sys_open fs/open.c:1444 [inline]
__do_sys_openat fs/open.c:1460 [inline]
__se_sys_openat fs/open.c:1455 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1455
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe5c7f8e969
RSP: 002b:00007fe5c8e56038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fe5c81b6080 RCX: 00007fe5c7f8e969
RDX: 0000000000101042 RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007fe5c8010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000035 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fe5c81b6080 R15: 00007ffe134c9268
Showing all locks held in the system:
4 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90000127c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
3 locks held by kworker/u8:2/36:
#0: ffff88814d1bb148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814d1bb148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90000ad7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000ad7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
2 locks held by dhcpcd/5484:
#0: ffffffff8f2c7228 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273
#1: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:554
2 locks held by getty/5581:
#0: ffff8880308be0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036d32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/0:7/5927:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90004827c60 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90004827c60 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
5 locks held by syz.0.94/6658:
#0: ffff888060a04420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
#2: ffff88805b2b1bf8 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
#3: ffff888052104228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888052104228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888052104228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385
#4: ffff888052126590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by syz.0.94/6704:
#0: ffff888060a04420 (sb_writers#22){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: open_last_lookups fs/namei.c:3797 [inline]
#1: ffff88805b2b1810 (&sb->s_type->i_mutex_key#28){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4036
1 lock held by bch-copygc/loop/6699:
1 lock held by syz-executor/8138:
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x3b0/0x18b0 net/ipv4/devinet.c:979
1 lock held by syz-executor/8218:
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5031
4 locks held by syz-executor/8273:
#0: ffff888034432420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff888034432420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680
#1: ffff888012283888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
#2: ffff88814476f968 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8eb82668 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:166
7 locks held by syz-executor/8332:
#0: ffff888034432420 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff888034432420 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xa90 fs/read_write.c:680
#1: ffff88804bee1c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0 fs/kernfs/file.c:325
#2: ffff88814476f968 (kn->active#53){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0 fs/kernfs/file.c:326
#3: ffffffff8eb82668 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: new_device_store+0x12c/0x6f0 drivers/net/netdevsim/bus.c:166
#4: ffff8880325b60e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline]
#4: ffff8880325b60e8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004
#5: ffff8880325b4250 (&devlink->lock_key#12){+.+.}-{4:4}, at: nsim_drv_probe+0xc1/0xb70 drivers/net/netdevsim/dev.c:1537
#6: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:948 [inline]
#6: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x7df/0xef0 drivers/net/netdevsim/netdev.c:1028
1 lock held by syz-executor/8414:
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f2e2748 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4064
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 36 Comm: kworker/u8:2 Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:__kasan_check_byte+0x2c/0x40 mm/kasan/common.c:561
Code: 1f 00 41 56 53 48 89 f3 49 89 fe e8 1e 12 00 00 84 c0 75 16 be 01 00 00 00 4c 89 f7 31 d2 48 89 d9 89 c3 e8 b6 03 00 00 89 d8 <5b> 41 5e c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90
RSP: 0018:ffffc90000007280 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffffff8171aa12 RCX: c7243e85e7bc4d00
RDX: 0000000000000000 RSI: ffffffff8171aa12 RDI: 1ffffffff1be770c
RBP: ffffffff8171a9f5 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000007458 R11: ffffffff81acbaf0 R12: 0000000000000002
R13: ffffffff8df3b860 R14: ffffffff8df3b860 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000056540648f4d8 CR3: 0000000032f32000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kasan_check_byte include/linux/kasan.h:399 [inline]
lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5840
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
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2380 [inline]
slab_free mm/slub.c:4642 [inline]
kmem_cache_free+0x192/0x3f0 mm/slub.c:4744
skb_kfree_head net/core/skbuff.c:1056 [inline]
skb_free_head net/core/skbuff.c:1070 [inline]
skb_release_data+0x670/0x890 net/core/skbuff.c:1097
skb_release_all net/core/skbuff.c:1162 [inline]
__kfree_skb net/core/skbuff.c:1176 [inline]
sk_skb_reason_drop+0x127/0x170 net/core/skbuff.c:1214
kfree_skb_reason include/linux/skbuff.h:1279 [inline]
kfree_skb include/linux/skbuff.h:1288 [inline]
ip6_mc_input+0x9c3/0xbe0 net/ipv6/ip6_input.c:591
NF_HOOK+0x309/0x3a0 include/linux/netfilter.h:314
__netif_receive_skb_one_core net/core/dev.c:5887 [inline]
__netif_receive_skb+0xd3/0x380 net/core/dev.c:6000
process_backlog+0x60e/0x14f0 net/core/dev.c:6352
__napi_poll+0xc4/0x480 net/core/dev.c:7324
napi_poll net/core/dev.c:7388 [inline]
net_rx_action+0x6ea/0xdf0 net/core/dev.c:7510
handle_softirqs+0x283/0x870 kernel/softirq.c:579
do_softirq+0xec/0x180 kernel/softirq.c:480
__local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:407
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:910 [inline]
__dev_queue_xmit+0x1cd7/0x3a70 net/core/dev.c:4656
neigh_output include/net/neighbour.h:539 [inline]
ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226
NF_HOOK include/linux/netfilter.h:314 [inline]
ndisc_send_skb+0xb47/0x1400 net/ipv6/ndisc.c:513
ndisc_send_ns+0xcb/0x150 net/ipv6/ndisc.c:671
addrconf_dad_work+0xaae/0x14b0 net/ipv6/addrconf.c:4286
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245