INFO: task kworker/u32:0:12 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u32:0 state:D stack:23448 pid:12 tgid:12 ppid:2 task_flags:0x4208160 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0xfee/0x6120 kernel/sched/core.c:6908 __schedule_loop kernel/sched/core.c:6990 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7005 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7062 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 hfsplus_cat_write_inode+0x323/0x8b0 fs/hfsplus/inode.c:650 hfsplus_write_inode+0x9f/0x580 fs/hfsplus/super.c:180 write_inode fs/fs-writeback.c:1582 [inline] __writeback_single_inode+0xd00/0x13c0 fs/fs-writeback.c:1813 writeback_sb_inodes+0x766/0x1c70 fs/fs-writeback.c:2042 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2118 wb_writeback+0x755/0xbe0 fs/fs-writeback.c:2229 wb_check_old_data_flush fs/fs-writeback.c:2333 [inline] wb_do_writeback fs/fs-writeback.c:2386 [inline] wb_workfn+0x8c6/0xc00 fs/fs-writeback.c:2414 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275 process_scheduled_works kernel/workqueue.c:3358 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3439 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 4 locks held by kworker/u32:0/12: #0: ffff88801cb7c148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250 #1: ffffc900000f7d08 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251 #2: ffff888024eea0e0 (&type->s_umount_key#70){.+.+}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:565 #3: ffff8880376260b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x18f/0x2f0 fs/hfsplus/bfind.c:28 1 lock held by khungtaskd/41: #0: ffffffff8e7e75e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7e75e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7e75e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by klogd/5326: 2 locks held by getty/5726: #0: ffff88802d0080a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000cd2f0 (&ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 8 locks held by syz-executor.0/6116: 4 locks held by syz-executor.0/20652: #0: ffff88803a963988 ( vm_lock){++++}-{0:0} , at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:647 #1: ffffffff9b1d4d48 (&____s->seqcount #2 ){----}-{0:0} , at: sched_info_arrive kernel/sched/stats.h:285 [inline] , at: sched_info_switch kernel/sched/stats.h:339 [inline] , at: prepare_task_switch kernel/sched/core.c:5082 [inline] , at: context_switch kernel/sched/core.c:5240 [inline] , at: __schedule+0x3ac1/0x6120 kernel/sched/core.c:6908 #2: ffff88802657ba38 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3} , at: spin_lock include/linux/spinlock.h:341 [inline] , at: pte_offset_map_lock+0x10f/0x320 mm/pgtable-generic.c:402 #3: ffffffff8e7e75e0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] , at: rcu_read_lock include/linux/rcupdate.h:850 [inline] , at: page_table_check_set+0x2be/0xa10 mm/page_table_check.c:112 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 41 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xd25/0x1050 kernel/hung_task.c:515 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x754/0xd80 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1-3: NMI backtrace for cpu 2 CPU: 2 UID: 0 PID: 5326 Comm: klogd Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:kasan_byte_accessible+0x15/0x30 mm/kasan/generic.c:210 Code: 00 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 40 d6 48 b8 00 00 00 00 00 fc ff df 48 c1 ef 03 48 01 c7 <0f> b6 07 3c 07 0f 96 c0 e9 0e 82 1d 09 66 66 2e 0f 1f 84 00 00 00 RSP: 0018:ffffc9000446f410 EFLAGS: 00000282 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff81b7feb1 RDI: fffffbfff1cfcebc RBP: ffffffff8e7e75e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000200 R11: 000000000001750d R12: ffffffff81b7feb1 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f30e6460c80(0000) GS:ffff8880d6547000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2ba52cf3ae CR3: 00000000369b4000 CR4: 0000000000352ef0 Call Trace: __kasan_check_byte+0x13/0x50 mm/kasan/common.c:573 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0x148/0x380 kernel/locking/lockdep.c:5825 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xd1/0x1ea0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x94/0xf0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5263 [inline] __kmalloc_node_track_caller_noprof+0x304/0x850 mm/slub.c:5371 kmalloc_reserve+0xe8/0x350 net/core/skbuff.c:635 __alloc_skb+0x185/0x710 net/core/skbuff.c:713 alloc_skb include/linux/skbuff.h:1383 [inline] alloc_skb_with_frags+0xe0/0x810 net/core/skbuff.c:6763 sock_alloc_send_pskb+0x801/0x980 net/core/sock.c:2995 unix_dgram_sendmsg+0x3c7/0x1820 net/unix/af_unix.c:2125 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] __sys_sendto+0x468/0x4b0 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f30e65b0407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fffabcb1a80 EFLAGS: 00000202 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f30e6460c80 RCX: 00007f30e65b0407 RDX: 000000000000004c RSI: 00007fffabcb1bc0 RDI: 0000000000000003 RBP: 00007fffabcb1ff0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000202 R12: 00007fffabcb2008 R13: 00007fffabcb1bc0 R14: 0000000000000031 R15: 00007fffabcb1bc0 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: e8 82 02 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 03 f1 1b 00 fb f4 fc 35 03 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000177df0 EFLAGS: 00000206 RAX: 0000000000199bd7 RBX: ffff88801e6d24c0 RCX: ffffffff8b8f9c75 RDX: 0000000000000000 RSI: ffffffff8de74cf8 RDI: ffffffff8c1afaa0 RBP: 0000000000000001 R08: 0000000000000001 R09: ffffed100d4a6795 R10: ffff88806a533cab R11: 0000000000000000 R12: ffffed1003cda498 R13: 0000000000000001 R14: ffffffff90d98310 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880d6447000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2ba53a8000 CR3: 000000000e598000 CR4: 0000000000352ef0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:73 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:191 [inline] do_idle+0x35b/0x4b0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148 NMI backtrace for cpu 3 CPU: 3 UID: 0 PID: 6116 Comm: syz-executor.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401 Code: 2a 8f fc 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 cc cc cc cc e8 48 ae fb fc eb a2 e8 d1 ae RSP: 0018:ffffc900028bf2d8 EFLAGS: 00000006 RAX: dffffc0000000005 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff85798fd0 RDI: ffffffff9b49ea40 RBP: ffffffff9b49ea00 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff9b49ecc0 R14: ffffffff9b49ea50 R15: 0000000000000000 FS: 00007f8c1bdd16c0(0000) GS:ffff8880d6647000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2ba53a8000 CR3: 000000002c6a3000 CR4: 0000000000352ef0 Call Trace: serial_port_in include/linux/serial_core.h:806 [inline] serial8250_console_write+0x246/0x1900 drivers/tty/serial/8250/8250_port.c:3306 console_emit_next_record kernel/printk/printk.c:3183 [inline] console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479 _printk+0xcf/0x110 kernel/printk/printk.c:2504 is_bnode_offset_valid fs/hfsplus/hfsplus_fs.h:561 [inline] hfsplus_bnode_read.cold+0xa9/0x270 fs/hfsplus/bnode.c:28 hfsplus_bnode_read_u16 fs/hfsplus/bnode.c:60 [inline] hfsplus_bnode_dump+0x164/0x870 fs/hfsplus/bnode.c:362 hfsplus_brec_remove+0x4ca/0x620 fs/hfsplus/brec.c:229 __hfsplus_delete_attr+0x234/0x390 fs/hfsplus/attributes.c:325 hfsplus_delete_all_attrs+0x160/0x2f0 fs/hfsplus/attributes.c:420 hfsplus_delete_cat+0x956/0xf60 fs/hfsplus/catalog.c:425 hfsplus_unlink+0x21c/0x9a0 fs/hfsplus/dir.c:406 vfs_unlink+0x2f0/0xbd0 fs/namei.c:5470 filename_unlinkat+0x408/0x730 fs/namei.c:5540 __do_sys_unlink fs/namei.c:5575 [inline] __se_sys_unlink fs/namei.c:5572 [inline] __x64_sys_unlink+0x46/0x70 fs/namei.c:5572 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x106/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8c1b06e3b9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 d0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f8c1bdd1078 EFLAGS: 00000246 ORIG_RAX: 0000000000000057 RAX: ffffffffffffffda RBX: 00007f8c1b1abf80 RCX: 00007f8c1b06e3b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000 RBP: 00007f8c1b0cf498 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f8c1b1abf80 R15: 00007ffc9e41e178