INFO: task syz-executor.4:16112 blocked for more than 143 seconds. Not tainted 5.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27416 16112 7264 0x00004004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x91f/0x2250 kernel/sched/core.c:4215 schedule+0xd0/0x2a0 kernel/sched/core.c:4290 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1884 __down_common kernel/locking/semaphore.c:220 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:237 down+0x57/0x80 kernel/locking/semaphore.c:61 console_lock+0x25/0x80 kernel/printk/printk.c:2309 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:688 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x501/0x1290 fs/open.c:828 do_open fs/namei.c:3243 [inline] path_openat+0x1bb9/0x2750 fs/namei.c:3360 do_filp_open+0x17e/0x3c0 fs/namei.c:3387 do_sys_openat2+0x16f/0x3b0 fs/open.c:1179 do_sys_open fs/open.c:1195 [inline] __do_sys_openat fs/open.c:1209 [inline] __se_sys_openat fs/open.c:1204 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1204 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: Bad RIP value. RSP: 002b:00007fe41ab0bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000022b80 RCX: 000000000045c369 RDX: 0000000000000080 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffc3b51335f R14: 00007fe41ab0c9c0 R15: 000000000078bf0c INFO: task syz-executor.4:16116 blocked for more than 143 seconds. Not tainted 5.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28664 16116 7264 0x00000004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x91f/0x2250 kernel/sched/core.c:4215 schedule+0xd0/0x2a0 kernel/sched/core.c:4290 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1884 __down_common kernel/locking/semaphore.c:220 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:237 down+0x57/0x80 kernel/locking/semaphore.c:61 console_lock+0x25/0x80 kernel/printk/printk.c:2309 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:688 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x501/0x1290 fs/open.c:828 do_open fs/namei.c:3243 [inline] path_openat+0x1bb9/0x2750 fs/namei.c:3360 do_filp_open+0x17e/0x3c0 fs/namei.c:3387 do_sys_openat2+0x16f/0x3b0 fs/open.c:1179 do_sys_open fs/open.c:1195 [inline] __do_sys_openat fs/open.c:1209 [inline] __se_sys_openat fs/open.c:1204 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1204 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: Bad RIP value. RSP: 002b:00007fe41aac9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000022b80 RCX: 000000000045c369 RDX: 0000000000000080 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 000000000078c088 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c04c R13: 00007ffc3b51335f R14: 00007fe41aaca9c0 R15: 000000000078c04c INFO: task syz-executor.5:16122 blocked for more than 143 seconds. Not tainted 5.8.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D26936 16122 7309 0x00004004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x91f/0x2250 kernel/sched/core.c:4215 schedule+0xd0/0x2a0 kernel/sched/core.c:4290 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4349 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x501/0x1290 fs/open.c:828 do_open fs/namei.c:3243 [inline] path_openat+0x1bb9/0x2750 fs/namei.c:3360 do_filp_open+0x17e/0x3c0 fs/namei.c:3387 do_sys_openat2+0x16f/0x3b0 fs/open.c:1179 do_sys_open fs/open.c:1195 [inline] __do_sys_openat fs/open.c:1209 [inline] __se_sys_openat fs/open.c:1204 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1204 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: Bad RIP value. RSP: 002b:00007f466ad83c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000021000 RCX: 000000000045c369 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffdec7d0acf R14: 00007f466ad849c0 R15: 000000000078bf0c Showing all locks held in the system: 2 locks held by kworker/u4:4/142: 1 lock held by khungtaskd/1153: #0: ffffffff89bc11c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6502: #0: ffff8880a13f9d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by kworker/u4:6/6773: 2 locks held by syz-executor.3/16110: 1 lock held by syz-executor.5/16122: #0: ffff8880a39e0078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a39e0078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1153 Comm: khungtaskd Not tainted 5.8.0-rc6-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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 142 Comm: kworker/u4:4 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: bat_events batadv_nc_worker RIP: 0010:task_wait_context kernel/locking/lockdep.c:3994 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4075 [inline] RIP: 0010:__lock_acquire+0x63b/0x56e0 kernel/locking/lockdep.c:4330 Code: 41 8b 84 24 8c 08 00 00 85 c0 0f 85 77 0a 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 4c 24 40 48 89 ce 48 c1 ee 03 0f b6 34 06 <48> 89 c8 83 e0 07 83 c0 03 40 38 f0 7c 09 40 84 f6 0f 85 a3 46 00 RSP: 0018:ffffc900014179c8 EFLAGS: 00000803 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a8e0ce74 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000001 RBP: ffff8880a8e0cee0 R08: 0000000000000000 R09: ffffffff8c59aa27 R10: fffffbfff18b3544 R11: 0000000000000001 R12: ffff8880a8e0c5c0 R13: ffff8880a8e0ce89 R14: dffffc0000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0002cf000 CR3: 00000000a9688000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1f1/0xad0 kernel/locking/lockdep.c:4959 rcu_lock_acquire include/linux/rcupdate.h:241 [inline] rcu_read_lock include/linux/rcupdate.h:634 [inline] batadv_nc_process_nc_paths.part.0+0xec/0x3b0 net/batman-adv/network-coding.c:686 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:678 [inline] batadv_nc_worker+0xaf2/0xe50 net/batman-adv/network-coding.c:727 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