| Message ID | 20230307073155.3.Ie678853bb101091afe78cc8c22344bf3ff3aed74@changeid (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | [1/3] tty: serial: qcom-geni-serial: Fix kdb/kgdb after port shutdown (again) | expand |
diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 74a0e074c2de..00752ff783c6 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -1534,6 +1534,7 @@ static const struct uart_ops qcom_geni_console_pops = { #ifdef CONFIG_CONSOLE_POLL .poll_get_char = qcom_geni_serial_get_char, .poll_put_char = qcom_geni_serial_poll_put_char, + .poll_init = qcom_geni_serial_port_setup, #endif .pm = qcom_geni_serial_pm, };
On sc7180 Chromebooks, I did the following: * Didn't enable earlycon in the kernel command line. * Didn't enable serial console in the kernel command line. * Didn't enable an agetty or any other client of "/dev/ttyMSM0". * Added "kgdboc=ttyMSM0" to the kernel command line. After I did that, I tried to enter kdb with this command over an ssh session: echo g > /proc/sysrq-trigger When I did that the system just hung. Although I thought I'd tested this scenario before, I couldn't go back and find a time when it was working. Previous testing must have relied on either the UART acting as the kernel console or an agetty running. It turns out to be pretty easy to fix: we can just use qcom_geni_serial_port_setup() as the .poll_init() function. This, together with the patch ("serial: uart_poll_init() should power on the UART"), allows the debugger to work even if there are no other users of the serial port. Signed-off-by: Douglas Anderson <dianders@chromium.org> --- drivers/tty/serial/qcom_geni_serial.c | 1 + 1 file changed, 1 insertion(+)