R13: ffffffffffffffff R14: 00000000201f9000 R15: 0000000000000000
WARNING: CPU: 1 PID: 3157 at drivers/tty/tty_ldisc.c:531 tty_ldisc_restore drivers/tty/tty_ldisc.c:531 [inline]
WARNING: CPU: 1 PID: 3157 at drivers/tty/tty_ldisc.c:531 tty_set_ldisc+0x4c6/0x7a0 drivers/tty/tty_ldisc.c:599
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3157 Comm: syz-executor0 Not tainted 4.15.0-rc4-mm1+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:177
 fixup_bug arch/x86/kernel/traps.c:246 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:1079
RIP: 0010:tty_ldisc_restore drivers/tty/tty_ldisc.c:531 [inline]
RIP: 0010:tty_set_ldisc+0x4c6/0x7a0 drivers/tty/tty_ldisc.c:599
RSP: 0018:ffff8801c8907b38 EFLAGS: 00010293
RAX: ffff8801c989c100 RBX: ffff8801c8940600 RCX: ffffffff8294a896
RDX: 0000000000000000 RSI: 1ffff10039313938 RDI: 0000000000000286
RBP: ffff8801c8907b88 R08: 1ffff10039120f27 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00000000ffffffff
R13: ffff8801c8940b70 R14: ffff8801ca3ead80 R15: fffffffffffffff4
 tiocsetd drivers/tty/tty_io.c:2321 [inline]
 tty_ioctl+0x492/0x1610 drivers/tty/tty_io.c:2565
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452ac9
RSP: 002b:0000000000a2f898 EFLAGS: 00000212 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000452ac9
RDX: 00000000201f9000 RSI: 0000000000005423 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: fffffffffffffffe
R13: ffffffffffffffff R14: 00000000201f9000 R15: 0000000000000000
Dumping ftrace buffer:
   (ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..