syzbot

Internal error: synchronous external abort: 97140050 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 31164 Comm: syz-executor.0 Not tainted 5.17.0-syzkaller-11407-gae085d7f9365 #0
Hardware name: linux,dummy-virt (DT)
pstate: 804000c9 (Nzcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __raw_writeb arch/arm64/include/asm/io.h:27 [inline]
pc : _outb include/asm-generic/io.h:501 [inline]
pc : logic_outb+0x3c/0xa4 lib/logic_pio.c:302
lr : io_serial_out+0x2c/0x3c drivers/tty/serial/8250/8250_port.c:458
sp : ffff80000b62bbb0
x29: ffff80000b62bbb0 x28: ffff80000b62bd70 x27: f1ff00002b9f3000
x26: 0000000000000fff x25: f7ff80000b9e32a0 x24: 0000000000000001
x23: f7ff80000b9e1000 x22: 0000000000000001 x21: ffff80000b62bd70
x20: 0000000000000002 x19: fffffbfffe800001 x18: 00000000fffffffb
x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000020
x14: 0000000000000000 x13: ffff80000b62bd78 x12: ffff80000b62bd3a
x11: 0000000000000000 x10: 0000000000000066 x9 : 0000000000000000
x8 : ffff8000080102a0 x7 : ffff80000b62bd71 x6 : 0000000000001000
x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffff80000a5b4bc0
x2 : 0000000000000000 x1 : fffffbfffe800000 x0 : 0000000000ffbffe
Call trace:
 _outb include/asm-generic/io.h:501 [inline]
 logic_outb+0x3c/0xa4 lib/logic_pio.c:302
 io_serial_out+0x2c/0x3c drivers/tty/serial/8250/8250_port.c:458
 serial_out drivers/tty/serial/8250/8250.h:120 [inline]
 serial8250_set_THRI drivers/tty/serial/8250/8250.h:140 [inline]
 __start_tx drivers/tty/serial/8250/8250_port.c:1568 [inline]
 serial8250_start_tx+0x94/0x18c drivers/tty/serial/8250/8250_port.c:1667
 __uart_start.isra.0+0x3c/0x50 drivers/tty/serial/serial_core.c:127
 uart_start+0x68/0x100 drivers/tty/serial/serial_core.c:137
 uart_flush_chars+0x10/0x20 drivers/tty/serial/serial_core.c:548
 __receive_buf drivers/tty/n_tty.c:1553 [inline]
 n_tty_receive_buf_common+0x328/0x1254 drivers/tty/n_tty.c:1645
 n_tty_receive_buf+0x14/0x24c drivers/tty/n_tty.c:1674
 tiocsti drivers/tty/tty_io.c:2293 [inline]
 tty_ioctl+0x95c/0xd24 drivers/tty/tty_io.c:2692
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xa8/0xf0 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x48/0x114 arch/arm64/kernel/syscall.c:52
 el0_svc_common.constprop.0+0x44/0xec arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x6c/0x84 arch/arm64/kernel/syscall.c:181
 el0_svc+0x44/0xb0 arch/arm64/kernel/entry-common.c:616
 el0t_64_sync_handler+0x1a4/0x1b0 arch/arm64/kernel/entry-common.c:634
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:581
Code: d2bfd001 f2df7fe1 f2ffffe1 8b010273 (39000274) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	d2bfd001 	mov	x1, #0xfe800000            	// #4269801472
   4:	f2df7fe1 	movk	x1, #0xfbff, lsl #32
   8:	f2ffffe1 	movk	x1, #0xffff, lsl #48
   c:	8b010273 	add	x19, x19, x1
* 10:	39000274 	strb	w20, [x19] <-- trapping instruction