INFO: task syz-executor.4:17756 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28264 17756 8967 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4080 schedule+0x188/0x210 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common+0x11f1/0x2f30 kernel/locking/mutex.c:1033 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_release+0x4d/0x1a0 drivers/video/fbdev/core/fbmem.c:1447 __fput+0x2e4/0x740 fs/file_table.c:280 ____fput+0x15/0x20 fs/file_table.c:313 task_work_run+0x176/0x1b0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:164 [inline] prepare_exit_to_usermode+0x480/0x5b0 arch/x86/entry/common.c:195 syscall_return_slowpath+0x113/0x4a0 arch/x86/entry/common.c:278 do_syscall_64+0x11f/0x1c0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x415fe1 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007ffd2134cff0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000415fe1 RDX: 0000000000000000 RSI: 000000000000054b RDI: 0000000000000005 RBP: 0000000000000001 R08: 000000005fdd254b R09: 000000005fdd254f R10: 00007ffd2134d0d0 R11: 0000000000000293 R12: 000000000076c920 R13: 000000000076c920 R14: 0000000000075bb7 R15: 000000000076c06c INFO: task syz-executor.5:17780 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28360 17780 8972 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4080 schedule+0x188/0x210 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common+0x11f1/0x2f30 kernel/locking/mutex.c:1033 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0x15e/0x3e0 drivers/video/fbdev/core/fbmem.c:1418 chrdev_open+0x509/0x590 fs/char_dev.c:414 do_dentry_open+0x85b/0x10c0 fs/open.c:797 vfs_open+0x73/0x80 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x16f1/0x4380 fs/namei.c:3607 do_filp_open+0x192/0x3d0 fs/namei.c:3637 do_sys_openat2+0x42b/0x6f0 fs/open.c:1149 do_sys_open fs/open.c:1165 [inline] __do_sys_openat fs/open.c:1179 [inline] __se_sys_openat fs/open.c:1174 [inline] __x64_sys_openat+0x1e6/0x210 fs/open.c:1174 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb9ac487c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fb9ac4886d4 RCX: 000000000045c449 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000799 R14: 00000000004ca0ae R15: 000000000076bf2c INFO: task syz-executor.5:17803 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27384 17803 8972 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4080 schedule+0x188/0x210 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common+0x11f1/0x2f30 kernel/locking/mutex.c:1033 __mutex_lock kernel/locking/mutex.c:1103 [inline] mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0x15e/0x3e0 drivers/video/fbdev/core/fbmem.c:1418 chrdev_open+0x509/0x590 fs/char_dev.c:414 do_dentry_open+0x85b/0x10c0 fs/open.c:797 vfs_open+0x73/0x80 fs/open.c:914 do_last fs/namei.c:3490 [inline] path_openat+0x16f1/0x4380 fs/namei.c:3607 do_filp_open+0x192/0x3d0 fs/namei.c:3637 do_sys_openat2+0x42b/0x6f0 fs/open.c:1149 do_sys_open fs/open.c:1165 [inline] __do_sys_openat fs/open.c:1179 [inline] __se_sys_openat fs/open.c:1174 [inline] __x64_sys_openat+0x1e6/0x210 fs/open.c:1174 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb9ac424c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fb9ac4256d4 RCX: 000000000045c449 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000076c100 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000799 R14: 00000000004ca0ae R15: 000000000076c10c Showing all locks held in the system: 2 locks held by kworker/u4:0/7: 4 locks held by kworker/u4:4/200: 1 lock held by khungtaskd/1129: #0: ffffffff892d9908 (rcu_read_lock){....}, at: rcu_lock_acquire+0x4/0x30 include/linux/rcupdate.h:207 1 lock held by rsyslogd/8821: #0: ffff8880a869fd60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x279/0x310 fs/file.c:821 2 locks held by getty/8911: #0: ffff88808e8bd090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900017bb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8912: #0: ffff88809a0e0090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900017fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8913: #0: ffff8880918a3090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc9000182b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8914: #0: ffff8880a693c090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc9000185b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8915: #0: ffff8880a7854090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc900017db2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8916: #0: ffff8880a9533090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc9000184b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 2 locks held by getty/8917: #0: ffff8880951a8090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:267 #1: ffffc9000179b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x22f/0x1bc0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.4/17756: #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: fb_release+0x4d/0x1a0 drivers/video/fbdev/core/fbmem.c:1447 2 locks held by syz-executor.4/17762: 1 lock held by syz-executor.5/17780: #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: fb_open+0x15e/0x3e0 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.5/17803: #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a3a37070 (&fb_info->lock){+.+.}, at: fb_open+0x15e/0x3e0 drivers/video/fbdev/core/fbmem.c:1418 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1129 Comm: khungtaskd Not tainted 5.6.0-rc3-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+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaa/0x190 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x16f/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace+0x17/0x20 include/linux/nmi.h:146 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xd40/0xd60 kernel/hung_task.c:289 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 200 Comm: kworker/u4:4 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:lock_release+0x4c4/0x710 kernel/locking/lockdep.c:4505 Code: 03 80 3c 18 00 74 0c 48 c7 c7 10 d3 2a 89 e8 63 44 58 00 48 83 3d 7b e4 ce 07 00 0f 84 28 02 00 00 48 8b bd 78 ff ff ff 57 9d <0f> 1f 44 00 00 65 48 8b 04 25 28 00 00 00 48 3b 45 d0 0f 85 09 02 RSP: 0018:ffffc900012e7ad0 EFLAGS: 00000282 RAX: 1ffffffff1255a62 RBX: dffffc0000000000 RCX: dffffc0000000000 RDX: ffff8880a8d86dd0 RSI: ffff8880a8d86e70 RDI: 0000000000000282 RBP: ffffc900012e7b58 R08: dffffc0000000000 R09: fffffbfff12d3725 R10: fffffbfff12d3725 R11: 0000000000000000 R12: ffff8880a8d86dd4 R13: 1ffff110151b0dba R14: 7a4809f1d969edb5 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c015ae2000 CR3: 00000000a7579000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release+0x21/0x30 include/linux/rcupdate.h:213 rcu_read_unlock include/linux/rcupdate.h:655 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:771 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:821 [inline] batadv_iv_ogm_schedule+0x671/0xf00 net/batman-adv/bat_iv_ogm.c:865 batadv_iv_send_outstanding_bat_ogm_packet+0x664/0x770 net/batman-adv/bat_iv_ogm.c:1718 process_one_work+0x7f5/0x10f0 kernel/workqueue.c:2264 worker_thread+0xbbc/0x1630 kernel/workqueue.c:2410 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352