If the device used as a serial console gets un/re-binded, then
register_console() will call imx_uart_setup_console() again.
Drop __init so that imx_uart_setup_console() can be safely called
at runtime.
Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
This addresses a kernel panic seen when unbinding/rebinding the i.MX
UART which is serial console on i.MX 6/7 via SSH:
# cd /sys/bus/platform/drivers/imx-uart/
# echo 30860000.serial > unbind && echo 30860000.serial > bind
console [ttymxc0] disabled
30860000.serial: ttymxc0 at MMIO 0x30860000 (irq = 52, base_baud = 1500000) is a IMX
Unable to handle kernel paging request at virtual address c0c4b830
pgd = 5e12e3d4
[c0c4b830] *pgd=80c1141e(bad)
Internal error: Oops: 8000000d [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 866 Comm: sh Not tainted 4.18.15-00048-gb3b505988801-dirty #403
Hardware name: Freescale i.MX7 Dual (Device Tree)
PC is at imx_uart_console_setup+0x0/0x274
LR is at register_console+0x184/0x3c4
pc : [<c0c4b830>] lr : [<c0171314>] psr: a0070013
sp : e8015db8 ip : c0d06548 fp : c0b4a158
r10: ec1d9380 r9 : 00000001 r8 : 00000000
r7 : 00000000 r6 : c0d819e0 r5 : c0d81e48 r4 : c0d47d68
r3 : c0c4b830 r2 : 00000000 r1 : efffca03 r0 : c0d47d68
Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: a803806a DAC: 00000051
Process sh (pid: 866, stack limit = 0x9c2f1d49)
It seems that also other drivers are affected. An alternative might be
to disallow unbinding/rebinding instead.
drivers/tty/serial/imx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 757c91e5105a..674bd0ea2491 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -1966,7 +1966,7 @@ imx_uart_console_write(struct console *co, const char *s, unsigned int count)
* If the port was already initialised (eg, by a boot loader),
* try to determine the current setup.
*/
-static void __init
+static void
imx_uart_console_get_options(struct imx_port *sport, int *baud,
int *parity, int *bits)
{
@@ -2025,7 +2025,7 @@ imx_uart_console_get_options(struct imx_port *sport, int *baud,
}
}
-static int __init
+static int
imx_uart_console_setup(struct console *co, char *options)
{
struct imx_port *sport;
--
2.19.1
