INFO: task syz-executor.3:12397 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:26104 pid:12397 ppid: 6873 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0xea9/0x2230 kernel/sched/core.c:4527 schedule+0xd0/0x2a0 kernel/sched/core.c:4602 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855 __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:2317 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:688 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4b9/0x11b0 fs/open.c:817 do_open fs/namei.c:3251 [inline] path_openat+0x1b9a/0x2730 fs/namei.c:3368 do_filp_open+0x17e/0x3c0 fs/namei.c:3395 do_sys_openat2+0x16d/0x420 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_sys_openat fs/open.c:1200 [inline] __se_sys_openat fs/open.c:1195 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1195 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: Bad RIP value. RSP: 002b:00007fad855a0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000024200 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 00000000ffffff9c RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffd45c2b3ff R14: 00007fad855a19c0 R15: 000000000118cf4c Showing all locks held in the system: 1 lock held by khungtaskd/1171: #0: ffffffff89bd6a40 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5829 1 lock held by in:imklog/6743: #0: ffff8880a90d6670 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 2 locks held by agetty/6745: #0: ffff88809d927098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc900011b02e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 5 locks held by syz-executor.2/12384: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1171 Comm: khungtaskd Not tainted 5.9.0-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+0x198/0x1fd 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:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 12384 Comm: syz-executor.2 Not tainted 5.9.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x9/0x60 kernel/kcov.c:197 Code: 5d be 03 00 00 00 e9 96 21 27 02 66 0f 1f 44 00 00 48 8b be b0 01 00 00 e8 b4 ff ff ff 31 c0 c3 90 65 48 8b 14 25 c0 fe 01 00 <65> 8b 05 70 b3 8d 7e a9 00 01 ff 00 48 8b 34 24 74 0f f6 c4 01 74 RSP: 0018:ffffc9000765f090 EFLAGS: 00000282 RAX: 00000000ed9714f0 RBX: 0000000000000050 RCX: ffffffff83cae130 RDX: ffff8880447fc400 RSI: ffff8880447fc400 RDI: 0000000000000005 RBP: 0000000000000050 R08: 0000000000000010 R09: 0000000000000280 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880000a0050 R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000ed9714f0 FS: 00007f5288306700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c00035b000 CR3: 00000000a8749000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vga16fb_fillrect+0x9a9/0x193b drivers/video/fbdev/vga16fb.c:922 bit_clear+0x386/0x4d0 drivers/video/fbdev/core/bitblit.c:74 fbcon_clear+0x519/0x5a0 drivers/video/fbdev/core/fbcon.c:1351 fbcon_scroll+0x1e20/0x3600 drivers/video/fbdev/core/fbcon.c:1980 con_scroll+0x5b9/0x6d0 drivers/tty/vt/vt.c:629 lf+0x26b/0x2c0 drivers/tty/vt/vt.c:1490 do_con_trol+0x20f/0x51e0 drivers/tty/vt/vt.c:2168 do_con_write+0xb7f/0x1d70 drivers/tty/vt/vt.c:2906 con_write+0x22/0xb0 drivers/tty/vt/vt.c:3250 do_output_char+0x5de/0x850 drivers/tty/n_tty.c:447 process_output drivers/tty/n_tty.c:514 [inline] n_tty_write+0x481/0xf80 drivers/tty/n_tty.c:2345 do_tty_write drivers/tty/tty_io.c:962 [inline] tty_write+0x4d9/0x870 drivers/tty/tty_io.c:1046 __kernel_write+0x199/0x570 fs/read_write.c:528 write_pipe_buf+0x153/0x1f0 fs/splice.c:799 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x3dc/0x830 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] default_file_splice_write fs/splice.c:811 [inline] do_splice_from fs/splice.c:847 [inline] direct_splice_actor+0x228/0x2f0 fs/splice.c:1016 splice_direct_to_actor+0x38c/0x980 fs/splice.c:971 do_splice_direct+0x1b3/0x280 fs/splice.c:1059 do_sendfile+0x55f/0xd40 fs/read_write.c:1540 __do_sys_sendfile64 fs/read_write.c:1601 [inline] __se_sys_sendfile64 fs/read_write.c:1587 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1587 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5b9 Code: 5d b4 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 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f5288305c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000027980 RCX: 000000000045d5b9 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 RBP: 000000000118cf88 R08: 0000000000000000 R09: 0000000000000000 R10: 0800000080004103 R11: 0000000000000246 R12: 000000000118cf4c R13: 00007ffef18f0e1f R14: 00007f52883069c0 R15: 000000000118cf4c