From babeca85847754ff62af58740bad0db731c3075a Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Tue, 30 Oct 2018 15:11:03 -0700 Subject: [PATCH] serial: qcom_geni_serial: Finish supporting sysrq The geni serial driver already had some sysrq code in it, but since SUPPORT_SYSRQ wasn't defined the code didn't do anything useful. Let's make it useful by adding that define using the same formula found in other serial drivers. In order to prevent deadlock, we'll take a page from the 'msm_serial.c' where the spinlock is released around uart_handle_sysrq_char(). This seemed better than copying from '8250_port.c' where we skip locking in the console_write function since the '8250_port.c' method can cause lockdep warnings when dropping into kgdb. Signed-off-by: Douglas Anderson Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/qcom_geni_serial.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 3040998ac8585..864c0e8aa84b8 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -1,6 +1,10 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (c) 2017-2018, The Linux foundation. All rights reserved. +#if defined(CONFIG_SERIAL_QCOM_GENI_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +# define SUPPORT_SYSRQ +#endif + #include #include #include @@ -493,7 +497,10 @@ static int handle_rx_console(struct uart_port *uport, u32 bytes, bool drop) continue; } + spin_unlock(&uport->lock); sysrq = uart_handle_sysrq_char(uport, buf[c]); + spin_lock(&uport->lock); + if (!sysrq) tty_insert_flip_char(tport, buf[c], TTY_NORMAL); } -- 2.30.2