INFO: task syz-executor.2:13588 blocked for more than 143 seconds. Not tainted 5.14.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:29208 pid:13588 ppid: 8479 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4681 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5938 schedule+0xd3/0x270 kernel/sched/core.c:6017 rwsem_down_write_slowpath+0x7b9/0x11d0 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1407 tty_set_termios+0xfe/0x910 drivers/tty/tty_ioctl.c:352 set_termios.part.0+0x30e/0x530 drivers/tty/tty_ioctl.c:438 set_termios drivers/tty/tty_ioctl.c:392 [inline] tty_mode_ioctl+0x34b/0xe70 drivers/tty/tty_ioctl.c:751 n_tty_ioctl_helper+0x53/0x2d0 drivers/tty/tty_ioctl.c:907 n_tty_ioctl+0x56/0x370 drivers/tty/n_tty.c:2421 tty_ioctl+0xef9/0x1600 drivers/tty/tty_io.c:2814 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 RSP: 002b:00007fba94fc7188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665e9 RDX: 0000000020000180 RSI: 00000000402c542b RDI: 0000000000000005 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffd33879d3f R14: 00007fba94fc7300 R15: 0000000000022000 INFO: task (agetty):13617 blocked for more than 143 seconds. Not tainted 5.14.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:(agetty) state:D stack:28408 pid:13617 ppid: 1 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4681 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5938 schedule+0xd3/0x270 kernel/sched/core.c:6017 rwsem_down_read_slowpath+0x4c5/0x990 kernel/locking/rwsem.c:992 __down_read_common kernel/locking/rwsem.c:1213 [inline] __down_read kernel/locking/rwsem.c:1222 [inline] down_read+0xe4/0x440 kernel/locking/rwsem.c:1355 copy_termios drivers/tty/tty_ioctl.c:449 [inline] tty_mode_ioctl+0x518/0xe70 drivers/tty/tty_ioctl.c:737 n_tty_ioctl_helper+0x53/0x2d0 drivers/tty/tty_ioctl.c:907 n_tty_ioctl+0x56/0x370 drivers/tty/n_tty.c:2421 tty_ioctl+0xef9/0x1600 drivers/tty/tty_io.c:2814 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f74f746880a RSP: 002b:00007ffd24dde9d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f74f746880a RDX: 00007ffd24dde9d0 RSI: 0000000000005401 RDI: 0000000000000003 RBP: 0000000000000015 R08: 00007ffd24ddea10 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000080902 R13: 00005582f681c060 R14: 00005582f68181a0 R15: 00007ffd24dded20 Showing all locks held in the system: 1 lock held by khungtaskd/1616: #0: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/8143: #0: ffff8880288e34f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 2 locks held by syz-executor.2/13588: #0: ffff88807534b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffff88807534b2e8 (&tty->termios_rwsem){++++}-{3:3}, at: tty_set_termios+0xfe/0x910 drivers/tty/tty_ioctl.c:352 6 locks held by syz-executor.2/13592: 2 locks held by (agetty)/13617: #0: ffff88807534b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffff88807534b2e8 (&tty->termios_rwsem){++++}-{3:3}, at: copy_termios drivers/tty/tty_ioctl.c:449 [inline] #1: ffff88807534b2e8 (&tty->termios_rwsem){++++}-{3:3}, at: tty_mode_ioctl+0x518/0xe70 drivers/tty/tty_ioctl.c:737 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1616 Comm: khungtaskd Not tainted 5.14.0-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:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xd0a/0xfc0 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 13592 Comm: syz-executor.2 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:slow_down_io arch/x86/include/asm/paravirt.h:55 [inline] RIP: 0010:outb_p arch/x86/include/asm/io.h:334 [inline] RIP: 0010:vga_io_w include/video/vga.h:209 [inline] RIP: 0010:vga_io_rgfx include/video/vga.h:388 [inline] RIP: 0010:setmode drivers/video/fbdev/vga16fb.c:124 [inline] RIP: 0010:vga_imageblit_expand drivers/video/fbdev/vga16fb.c:1161 [inline] RIP: 0010:vga16fb_imageblit+0x75b/0x2200 drivers/video/fbdev/vga16fb.c:1260 Code: 31 ff 8b 40 58 89 c3 89 c6 89 44 24 30 e8 3d 97 68 fd 85 db 0f 84 f7 04 00 00 e8 f0 8f 68 fd b8 05 00 00 00 ba ce 03 00 00 ee <41> ff d4 ba cf 03 00 00 ec 48 c7 c2 a0 28 7f 8b 48 b8 00 00 00 00 RSP: 0018:ffffc9000d2c7088 EFLAGS: 00000246 RAX: 0000000000000005 RBX: 0000000000000001 RCX: ffffc9000e311000 RDX: 00000000000003ce RSI: ffffffff840d1910 RDI: 0000000000000003 RBP: ffffc9000d2c7214 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff840d1903 R11: 0000000000000001 R12: ffffffff81330c30 R13: ffff888140b85848 R14: ffffc9000d2c7230 R15: ffffc9000d2c7210 FS: 00007fba94fa6700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c012f5d041 CR3: 0000000060976000 CR4: 0000000000350ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline] bit_putcs+0x6e1/0xd20 drivers/video/fbdev/core/bitblit.c:188 fbcon_putcs+0x35a/0x450 drivers/video/fbdev/core/fbcon.c:1296 fbcon_redraw.constprop.0+0x41a/0x4b0 drivers/video/fbdev/core/fbcon.c:1672 fbcon_scroll+0x1d7a/0x3580 drivers/video/fbdev/core/fbcon.c:1782 con_scroll+0x5b9/0x6d0 drivers/tty/vt/vt.c:630 lf+0x26b/0x2c0 drivers/tty/vt/vt.c:1490 vc_con_write_normal drivers/tty/vt/vt.c:2811 [inline] do_con_write+0xf1c/0x1e40 drivers/tty/vt/vt.c:2915 con_put_char+0x70/0xa0 drivers/tty/vt/vt.c:3263 tty_put_char+0xb7/0x150 drivers/tty/tty_io.c:3173 do_output_char+0x155/0x850 drivers/tty/n_tty.c:485 __process_echoes+0x38e/0x9f0 drivers/tty/n_tty.c:736 commit_echoes+0x148/0x210 drivers/tty/n_tty.c:791 n_tty_receive_char+0x3b0/0x5b0 drivers/tty/n_tty.c:1411 n_tty_receive_buf_standard drivers/tty/n_tty.c:1560 [inline] __receive_buf drivers/tty/n_tty.c:1577 [inline] n_tty_receive_buf_common+0x109e/0x4780 drivers/tty/n_tty.c:1674 tty_ldisc_receive_buf+0xa3/0x190 drivers/tty/tty_buffer.c:471 paste_selection+0x1de/0x4c0 drivers/tty/vt/selection.c:408 tioclinux+0x126/0x560 drivers/tty/vt/vt.c:3164 vt_ioctl+0x225f/0x2ac0 drivers/tty/vt/vt_ioctl.c:760 tty_ioctl+0xe4d/0x1600 drivers/tty/tty_io.c:2805 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fba94fa6188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c0f0 RCX: 00000000004665e9 RDX: 0000000020000100 RSI: 000000000000541c RDI: 0000000000000005 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c0f0 R13: 00007ffd33879d3f R14: 00007fba94fa6300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 31 ff xor %edi,%edi 2: 8b 40 58 mov 0x58(%rax),%eax 5: 89 c3 mov %eax,%ebx 7: 89 c6 mov %eax,%esi 9: 89 44 24 30 mov %eax,0x30(%rsp) d: e8 3d 97 68 fd callq 0xfd68974f 12: 85 db test %ebx,%ebx 14: 0f 84 f7 04 00 00 je 0x511 1a: e8 f0 8f 68 fd callq 0xfd68900f 1f: b8 05 00 00 00 mov $0x5,%eax 24: ba ce 03 00 00 mov $0x3ce,%edx 29: ee out %al,(%dx) 2a: 41 ff d4 callq *%r12 <-- trapping instruction 2d: ba cf 03 00 00 mov $0x3cf,%edx 32: ec in (%dx),%al 33: 48 c7 c2 a0 28 7f 8b mov $0xffffffff8b7f28a0,%rdx 3a: 48 rex.W 3b: b8 00 00 00 00 mov $0x0,%eax