[PATCH 5/7] serial: 8250: Process sysrq at port unlock time
From: dianders@chromium.org (Douglas Anderson)
Date: 2018-10-29 18:08:35
Also in:
linux-arm-msm, linux-aspeed, linux-serial, lkml
Subsystem:
8250/16?50 (and clone uarts) serial driver, the rest, tty layer and serial drivers · Maintainers:
Greg Kroah-Hartman, Linus Torvalds, Jiri Slaby
Let's take advantage of the new ("serial: core: Allow processing sysrq
at port unlock time") to handle sysrqs more cleanly.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
I don't have a great way to test all 8250 variants, but I've at least
tested rk3288 / rk3399 and they seem to work. Hopefully I got the
aspeed_vuart / fsl / omap variants right (I only compile tested
those).
drivers/tty/serial/8250/8250_aspeed_vuart.c | 6 +++++-
drivers/tty/serial/8250/8250_fsl.c | 6 +++++-
drivers/tty/serial/8250/8250_omap.c | 6 +++++-
drivers/tty/serial/8250/8250_port.c | 8 +++-----
4 files changed, 18 insertions(+), 8 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_aspeed_vuart.c b/drivers/tty/serial/8250/8250_aspeed_vuart.c
index 435bec40dee6..0438d9a905ce 100644
--- a/drivers/tty/serial/8250/8250_aspeed_vuart.c
+++ b/drivers/tty/serial/8250/8250_aspeed_vuart.c@@ -5,6 +5,10 @@ * Copyright (C) 2016 Jeremy Kerr <jk@ozlabs.org>, IBM Corp. * Copyright (C) 2006 Arnd Bergmann <arnd@arndb.de>, IBM Corp. */ +#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + #include <linux/device.h> #include <linux/module.h> #include <linux/of_address.h>
@@ -293,7 +297,7 @@ static int aspeed_vuart_handle_irq(struct uart_port *port) if (lsr & UART_LSR_THRE) serial8250_tx_chars(up); - spin_unlock_irqrestore(&port->lock, flags); + uart_unlock_and_check_sysrq(port, flags); return 1; }
diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
index 6640a4c7ddd1..ff3dcaea5d93 100644
--- a/drivers/tty/serial/8250/8250_fsl.c
+++ b/drivers/tty/serial/8250/8250_fsl.c@@ -1,4 +1,8 @@ // SPDX-License-Identifier: GPL-2.0 +#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + #include <linux/serial_reg.h> #include <linux/serial_8250.h>
@@ -54,7 +58,7 @@ int fsl8250_handle_irq(struct uart_port *port) serial8250_tx_chars(up); up->lsr_saved_flags = orig_lsr; - spin_unlock_irqrestore(&up->port.lock, flags); + uart_unlock_and_check_sysrq(&up->port, flags); return 1; } EXPORT_SYMBOL_GPL(fsl8250_handle_irq);
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index a019286f8bb6..ad7ba7d0f28d 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c@@ -8,6 +8,10 @@ * */ +#if defined(CONFIG_SERIAL_8250_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + #include <linux/device.h> #include <linux/io.h> #include <linux/module.h>
@@ -1085,7 +1089,7 @@ static int omap_8250_dma_handle_irq(struct uart_port *port) } } - spin_unlock_irqrestore(&port->lock, flags); + uart_unlock_and_check_sysrq(port, flags); serial8250_rpm_put(up); return 1; }
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index f776b3eafb96..c39482b96111 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c@@ -1755,7 +1755,7 @@ void serial8250_read_char(struct uart_8250_port *up, unsigned char lsr) else if (lsr & UART_LSR_FE) flag = TTY_FRAME; } - if (uart_handle_sysrq_char(port, ch)) + if (uart_prepare_sysrq_char(port, ch)) return; uart_insert_char(port, lsr, UART_LSR_OE, ch, flag);
@@ -1897,7 +1897,7 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) if ((!up->dma || up->dma->tx_err) && (status & UART_LSR_THRE)) serial8250_tx_chars(up); - spin_unlock_irqrestore(&port->lock, flags); + uart_unlock_and_check_sysrq(port, flags); return 1; } EXPORT_SYMBOL_GPL(serial8250_handle_irq);
@@ -3258,9 +3258,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s, serial8250_rpm_get(up); - if (port->sysrq) - locked = 0; - else if (oops_in_progress) + if (oops_in_progress) locked = spin_trylock_irqsave(&port->lock, flags); else spin_lock_irqsave(&port->lock, flags);
--
2.19.1.568.g152ad8e336-goog