INFO: task syz.6.3903:31487 blocked for more than 144 seconds. Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.6.3903 state:D stack:23600 pid:31487 tgid:31487 ppid:31263 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x184f/0x4c30 kernel/sched/core.c:6693 __schedule_loop kernel/sched/core.c:6770 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6785 request_wait_answer fs/fuse/dev.c:464 [inline] __fuse_request_send fs/fuse/dev.c:478 [inline] __fuse_simple_request+0xe17/0x1840 fs/fuse/dev.c:572 fuse_simple_request fs/fuse/fuse_i.h:1156 [inline] fuse_flush+0x69d/0x950 fs/fuse/file.c:542 filp_flush+0xac/0x150 fs/open.c:1527 filp_close+0x1e/0x40 fs/open.c:1540 close_files fs/file.c:418 [inline] put_files_struct+0x1b6/0x360 fs/file.c:433 do_exit+0xa10/0x28e0 kernel/exit.c:934 do_group_exit+0x207/0x2c0 kernel/exit.c:1088 get_signal+0x16a3/0x1740 kernel/signal.c:2918 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:328 [inline] irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0033:0x7facd125cb93 RSP: 002b:00007facd165fa70 EFLAGS: 00000286 RAX: ffffffff81952bb9 RBX: 00007facd2065720 RCX: ffffffff819528b6 RDX: 00007facd00b3658 RSI: ffffffff819528b6 RDI: 00007faccfff9000 RBP: 0000000000000000 R08: 00007facd1520000 R09: ffffffff815e68a5 R10: 00000000819528ba R11: 00000000000000ff R12: ffffffff81952bb9 R13: 00007facd1535f40 R14: 0000000000000008 R15: 00000000000174cb Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 3 locks held by kworker/u8:4/63: 3 locks held by kworker/u8:6/1143: #0: ffff88814d5f5148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88814d5f5148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc900040e7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900040e7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fcd3a48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4736 3 locks held by kworker/u8:7/1156: 1 lock held by klogd/5204: 1 lock held by udevd/5215: 2 locks held by getty/5601: #0: ffff8880350020a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5826: 4 locks held by kworker/1:6/5906: 3 locks held by udevd/5916: 3 locks held by kworker/u8:9/5964: 2 locks held by kworker/u8:10/15919: 3 locks held by kworker/u8:11/15920: 3 locks held by kworker/u8:12/15922: 3 locks held by kworker/u8:13/15923: 2 locks held by kworker/u8:14/17147: 3 locks held by kworker/u8:15/17148: 3 locks held by kworker/u8:0/27496: 1 lock held by syz-executor/31094: 2 locks held by syz-executor/31176: 2 locks held by syz-executor/31236: 1 lock held by syz.7.3902/31480: #0: ffffffff8e93d200 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4562 4 locks held by sed/31507: 2 locks held by syz-executor/31508: 2 locks held by kworker/u8:1/31509: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 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 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 969 Comm: kworker/1:2 Not tainted 6.12.0-rc7-syzkaller-00070-g0a9b9d17f3a7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 Workqueue: events dvb_usb_read_remote_control RIP: 0010:put_cpu_partial+0x15a/0x250 mm/slub.c:3217 Code: df 48 8b 34 24 e8 06 39 7d ff 48 8b 5c 24 08 f7 c3 00 02 00 00 74 05 e8 94 6b a9 ff 48 c7 44 24 10 00 00 00 00 9c 8f 44 24 10 44 24 10 00 02 00 00 75 3f f7 c3 00 02 00 00 75 44 4d 85 e4 74 RSP: 0018:ffffc90003a678b0 EFLAGS: 00000082 RAX: 11174b03e55a3a00 RBX: 0000000000000282 RCX: ffffffff8170cfaa RDX: dffffc0000000000 RSI: ffffffff8c0acac0 RDI: ffffffff8c610b20 RBP: 0000000000000001 R08: ffffffff942d0837 R09: 1ffffffff285a106 R10: dffffc0000000000 R11: fffffbfff285a107 R12: ffffea0007302e00 R13: ffffea0007303e00 R14: ffff888026095a00 R15: ffff88801ac41dc0 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa727000210 CR3: 000000003364a000 CR4: 00000000003526f0 Call Trace: __slab_free+0x2ea/0x3d0 mm/slub.c:4449 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_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] __kmalloc_cache_noprof+0x132/0x2c0 mm/slub.c:4290 kmalloc_noprof include/linux/slab.h:878 [inline] usb_control_msg+0xbb/0x4c0 drivers/usb/core/message.c:144 m920x_read drivers/media/usb/dvb-usb/m920x.c:36 [inline] m920x_rc_core_query+0xc6/0x510 drivers/media/usb/dvb-usb/m920x.c:226 dvb_usb_read_remote_control+0xb8/0x1b0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 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