INFO: task syz-executor.2:3928 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.2 D28384 3928 3430 0x00004004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x8ea/0x2210 kernel/sched/core.c:4219 schedule+0xd0/0x2a0 kernel/sched/core.c:4294 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4353 __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_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 __fput+0x33c/0x880 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:239 [inline] __prepare_exit_to_usermode+0x1e9/0x1f0 arch/x86/entry/common.c:269 do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x415ee1 Code: Bad RIP value. RSP: 002b:00007fff80cf14e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000415ee1 RDX: 0000001b32120000 RSI: 00000000000003c3 RDI: 0000000000000003 RBP: 0000000000000001 R08: 00000000633403c3 R09: 00000000633403c7 R10: 00007fff80cf15d0 R11: 0000000000000293 R12: 000000000078c900 R13: 000000000078c900 R14: ffffffffffffffff R15: 000000000078c0ec INFO: task syz-executor.3:3974 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.3 D25728 3974 3351 0x00004004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x8ea/0x2210 kernel/sched/core.c:4219 schedule+0xd0/0x2a0 kernel/sched/core.c:4294 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4353 __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] do_fb_ioctl+0x3bf/0x6c0 drivers/video/fbdev/core/fbmem.c:1117 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 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:00007f37cee85c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000d400 RCX: 000000000045c369 RDX: 0000000000000000 RSI: 0000000000004602 RDI: 0000000000000003 RBP: 000000000078bfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 00007ffc9c3ef47f R14: 00007f37cee869c0 R15: 000000000078bfac INFO: task syz-executor.3:3976 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.3 D26336 3976 3351 0x00000004 Call Trace: context_switch kernel/sched/core.c:3458 [inline] __schedule+0x8ea/0x2210 kernel/sched/core.c:4219 schedule+0xd0/0x2a0 kernel/sched/core.c:4294 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4353 __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:00007f37cee64c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000021000 RCX: 000000000045c369 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078c088 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c04c R13: 00007ffc9c3ef47f R14: 00007f37cee659c0 R15: 000000000078c04c Showing all locks held in the system: 1 lock held by khungtaskd/1150: #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/6521: #0: ffff88809ce0bd70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 1 lock held by syz-executor.2/3928: #0: ffff8880a45e4078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a45e4078 (&fb_info->lock){+.+.}-{3:3}, at: fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 2 locks held by syz-executor.3/3971: 1 lock held by syz-executor.3/3974: #0: ffff8880a45e4078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a45e4078 (&fb_info->lock){+.+.}-{3:3}, at: do_fb_ioctl+0x3bf/0x6c0 drivers/video/fbdev/core/fbmem.c:1117 1 lock held by syz-executor.3/3976: #0: ffff8880a45e4078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a45e4078 (&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: 1150 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: 3971 Comm: syz-executor.3 Not tainted 5.8.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x35/0x60 kernel/kcov.c:200 Code: 05 e0 41 8e 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 35 8b 82 04 14 00 00 85 c0 74 2b 8b 82 e0 13 00 00 83 f8 02 75 20 <48> 8b 8a e8 13 00 00 8b 92 e4 13 00 00 48 8b 01 48 83 c0 01 48 39 RSP: 0018:ffffc9000cf0f4e8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: 0000000000000000 RCX: ffffc9000ea63000 RDX: ffff88804faca580 RSI: ffffffff83c23338 RDI: 0000000000000007 RBP: 0000000000000040 R08: 0000000000000020 R09: 0000000000000040 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000020 R13: ffff8880000a0000 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007f37ceea7700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056227c6b1f67 CR3: 0000000092eb6000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __readq arch/x86/include/asm/io.h:96 [inline] bitfill_aligned drivers/video/fbdev/core/cfbfillrect.c:50 [inline] bitfill_aligned+0x98/0x200 drivers/video/fbdev/core/cfbfillrect.c:35 cfb_fillrect+0x40b/0x7b0 drivers/video/fbdev/core/cfbfillrect.c:327 vga16fb_fillrect+0x683/0x193b drivers/video/fbdev/vga16fb.c:951 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x1d5/0x230 drivers/video/fbdev/core/fbcon.c:1381 fbcon_switch+0xb6e/0x16c0 drivers/video/fbdev/core/fbcon.c:2363 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015 fbcon_modechanged+0x575/0x710 drivers/video/fbdev/core/fbcon.c:3001 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: 8d 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 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f37ceea6c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000d540 RCX: 000000000045c369 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffc9c3ef47f R14: 00007f37ceea79c0 R15: 000000000078bf0c