INFO: task kworker/1:136:2901 blocked for more than 143 seconds. Not tainted 5.8.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:136 D23920 2901 2 0x00004000 Workqueue: ipv6_addrconf addrconf_verify_work Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4312 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4543 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 INFO: task kworker/0:19:15820 blocked for more than 144 seconds. Not tainted 5.8.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:19 D27688 15820 2 0x00004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4312 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 linkwatch_event+0xb/0x60 net/core/link_watch.c:250 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Showing all locks held in the system: 1 lock held by khungtaskd/1148: #0: ffffffff89bc11c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 3 locks held by kworker/1:136/2901: #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88821536f938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc900090afda8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7b3e28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4543 1 lock held by in:imklog/6604: #0: ffff8880a2d1aaf0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by agetty/6637: #0: ffff8880a6baf098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900010942e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.1/10636: 3 locks held by kworker/0:19/15820: #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880aa026d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc900017b7da8 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7b3e28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:250 1 lock held by syz-executor.0/28140: 1 lock held by syz-executor.0/28186: 1 lock held by syz-executor.0/28224: 1 lock held by syz-executor.0/28257: 2 locks held by syz-executor.4/28425: 2 locks held by syz-executor.4/28431: 1 lock held by syz-executor.4/28437: 1 lock held by syz-executor.4/28451: 2 locks held by syz-executor.5/28466: 2 locks held by syz-executor.5/28474: 1 lock held by syz-executor.0/28478: 2 locks held by syz-executor.4/28503: 1 lock held by syz-executor.5/28504: 1 lock held by syz-executor.0/28515: 1 lock held by syz-executor.5/28525: 2 locks held by syz-executor.5/28539: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1148 Comm: khungtaskd Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 28525 Comm: syz-executor.5 Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count_add+0x3f/0x140 kernel/sched/core.c:3873 Code: 53 83 e0 07 89 fb 48 c1 e9 03 83 c0 03 0f b6 14 11 38 d0 7c 08 84 d2 0f 85 e1 00 00 00 8b 15 d8 8a 41 0b 65 01 1d f1 77 b2 7e <85> d2 75 11 65 8b 05 e6 77 b2 7e 0f b6 c0 3d f4 00 00 00 7f 64 65 RSP: 0018:ffffc90006ecf3c8 EFLAGS: 00000282 RAX: 0000000000000003 RBX: 0000000000000001 RCX: 1ffffffff1922234 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000001 R08: ffffffff8b17ad90 R09: 0000000000000001 R10: 000000000007201e R11: 0000000000000001 R12: ffffc90006ecf550 R13: fffff52000dd9ea2 R14: ffffc90006ecf540 R15: ffffc90006ecf508 FS: 0000000000000000(0000) GS:ffff8880ae600000(0063) knlGS:00000000f5d38b40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 000000c00901e018 CR3: 000000008f25b000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0x11f/0x1f90 arch/x86/kernel/unwind_orc.c:434 __unwind_start+0x4dd/0x7c0 arch/x86/kernel/unwind_orc.c:698 unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0x5e/0xf0 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123 save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc mm/slab.c:3320 [inline] __do_kmalloc mm/slab.c:3654 [inline] __kmalloc+0x164/0x340 mm/slab.c:3665 kmalloc_array include/linux/slab.h:597 [inline] kcalloc include/linux/slab.h:608 [inline] iter_file_splice_write+0x170/0xbe0 fs/splice.c:692 do_splice_from fs/splice.c:846 [inline] direct_splice_actor+0x171/0x2f0 fs/splice.c:1016 splice_direct_to_actor+0x38c/0x980 fs/splice.c:971 do_splice_direct+0x1b3/0x280 fs/splice.c:1059 do_sendfile+0x559/0xc30 fs/read_write.c:1540 __do_compat_sys_sendfile fs/read_write.c:1616 [inline] __se_compat_sys_sendfile fs/read_write.c:1605 [inline] __ia32_compat_sys_sendfile+0x159/0x220 fs/read_write.c:1605 do_syscall_32_irqs_on+0x3f/0x60 arch/x86/entry/common.c:428 __do_fast_syscall_32 arch/x86/entry/common.c:475 [inline] do_fast_syscall_32+0x7f/0x120 arch/x86/entry/common.c:503 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7f3d569 Code: Bad RIP value. RSP: 002b:00000000f5d380cc EFLAGS: 00000296 ORIG_RAX: 00000000000000bb RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000003 RDX: 00000000200001c0 RSI: 00000000fffffffe RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000