INFO: task syz-executor.0:10226 blocked for more than 143 seconds. Not tainted 5.8.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29696 10226 6823 0x00004004 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 schedule+0xd0/0x2a0 kernel/sched/core.c:4230 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4289 __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+0x15e/0x6c0 drivers/video/fbdev/core/fbmem.c:1168 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:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f52d2065c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e6300 RCX: 000000000045cb19 RDX: 0000000000000000 RSI: 0000000040086602 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000334 R14: 00000000004c5c8a R15: 00007f52d20666d4 INFO: task syz-executor.0:10227 blocked for more than 143 seconds. Not tainted 5.8.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28952 10227 6823 0x00000004 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 schedule+0xd0/0x2a0 kernel/sched/core.c:4230 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4289 __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+0x50c/0x6c0 drivers/video/fbdev/core/fbmem.c:1133 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:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f52d2044c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e5340 RCX: 000000000045cb19 RDX: 0000000020000200 RSI: 0000000000004604 RDI: 0000000000000003 RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002f5 R14: 00000000004c57dc R15: 00007f52d20456d4 INFO: task syz-executor.0:10231 blocked for more than 143 seconds. Not tainted 5.8.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D27120 10231 6823 0x00000004 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 schedule+0xd0/0x2a0 kernel/sched/core.c:4230 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4289 __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:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f52d2023c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00000000004f8600 RCX: 000000000045cb19 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078c0e0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000007c0 R14: 00000000004caad0 R15: 00007f52d20246d4 INFO: task syz-executor.3:10260 blocked for more than 143 seconds. Not tainted 5.8.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D27440 10260 7147 0x00004004 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 schedule+0xd0/0x2a0 kernel/sched/core.c:4230 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1873 __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 con_install+0x8c/0x5c0 drivers/tty/vt/vt.c:3252 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline] tty_init_dev.part.0+0x9e/0x610 drivers/tty/tty_io.c:1341 tty_init_dev include/linux/err.h:36 [inline] tty_open_by_driver drivers/tty/tty_io.c:1983 [inline] tty_open+0xb2e/0xf60 drivers/tty/tty_io.c:2031 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] ksys_open include/linux/syscalls.h:1388 [inline] __do_sys_open fs/open.c:1201 [inline] __se_sys_open fs/open.c:1199 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1199 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416911 Code: Bad RIP value. RSP: 002b:00007f2a2e1b77a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000050ac80 RCX: 0000000000416911 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00007f2a2e1b77d0 RBP: 000000000078bf00 R08: 0000000000000000 R09: 000000000000000e R10: 0000000000000064 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000c5a R14: 00000000004ceb45 R15: 00007f2a2e1b86d4 INFO: task syz-executor.3:10263 blocked for more than 143 seconds. Not tainted 5.8.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28608 10263 7147 0x00000004 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4155 schedule+0xd0/0x2a0 kernel/sched/core.c:4230 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4289 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 tty_open_by_driver drivers/tty/tty_io.c:1947 [inline] tty_open+0x51d/0xf60 drivers/tty/tty_io.c:2031 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] ksys_open include/linux/syscalls.h:1388 [inline] __do_sys_open fs/open.c:1201 [inline] __se_sys_open fs/open.c:1199 [inline] __x64_sys_open+0x119/0x1c0 fs/open.c:1199 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x416911 Code: Bad RIP value. RSP: 002b:00007f2a2e1967a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000000000050ac80 RCX: 0000000000416911 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00007f2a2e1967d0 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 000000000000000e R10: 0000000000000064 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000c5a R14: 00000000004ceb45 R15: 00007f2a2e1976d4 Showing all locks held in the system: 1 lock held by khungtaskd/1152: #0: ffffffff89bbe640 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6503: #0: ffff8880979c5870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by syz-executor.0/10225: 1 lock held by syz-executor.0/10226: #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: do_fb_ioctl+0x15e/0x6c0 drivers/video/fbdev/core/fbmem.c:1168 1 lock held by syz-executor.0/10227: #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: do_fb_ioctl+0x50c/0x6c0 drivers/video/fbdev/core/fbmem.c:1133 1 lock held by syz-executor.0/10231: #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff8880a361e078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 2 locks held by syz-executor.3/10260: #0: ffffffff8a1736c8 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:1947 [inline] #0: ffffffff8a1736c8 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x51d/0xf60 drivers/tty/tty_io.c:2031 #1: ffff88809ed661c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_lock+0xbd/0x120 drivers/tty/tty_mutex.c:19 1 lock held by syz-executor.3/10263: #0: ffffffff8a1736c8 (tty_mutex){+.+.}-{3:3}, at: tty_open_by_driver drivers/tty/tty_io.c:1947 [inline] #0: ffffffff8a1736c8 (tty_mutex){+.+.}-{3:3}, at: tty_open+0x51d/0xf60 drivers/tty/tty_io.c:2031 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1152 Comm: khungtaskd Not tainted 5.8.0-rc2-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: 10225 Comm: syz-executor.0 Not tainted 5.8.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_cmp4+0x4/0x20 kernel/kcov.c:258 Code: 84 00 00 00 00 00 48 8b 0c 24 0f b7 d6 0f b7 f7 bf 02 00 00 00 e9 4c ff ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 48 8b 0c 24 <89> f2 89 fe bf 04 00 00 00 e9 2e ff ff ff 0f 1f 40 00 66 2e 0f 1f RSP: 0018:ffffc900012c75a8 EFLAGS: 00000292 RAX: 0000000000040000 RBX: 0000000000000050 RCX: ffffffff83c5d814 RDX: 0000000000040000 RSI: 0000000000000040 RDI: 0000000000000050 RBP: 0000000000000040 R08: 0000000000000001 R09: ffff8880a365249f R10: 0000000000000050 R11: 0000000000000000 R12: ffff8880000a0040 R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000f3ec54d1 FS: 00007f52d2087700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0196841d0 CR3: 0000000054b60000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vga16fb_fillrect+0x9d4/0x193b drivers/video/fbdev/vga16fb.c:922 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:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb19 Code: Bad RIP value. RSP: 002b:00007f52d2086c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e5500 RCX: 000000000045cb19 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002fc R14: 00000000004c587a R15: 00007f52d20876d4