From: John Ogness Date: Fri, 6 May 2022 21:33:24 +0000 (+0206) Subject: serial: msm_serial: disable interrupts in __msm_console_write() X-Git-Tag: v5.15.73~3050 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d21ffa548737822fe8c0a8b77bdb9ddbd71323eb;p=platform%2Fkernel%2Flinux-rpi.git serial: msm_serial: disable interrupts in __msm_console_write() [ Upstream commit aabdbb1b7a5819e18c403334a31fb0cc2c06ad41 ] __msm_console_write() assumes that interrupts are disabled, but with threaded console printers it is possible that the write() callback of the console is called with interrupts enabled. Explicitly disable interrupts using local_irq_save() to preserve the assumed context. Reported-by: Marek Szyprowski Reviewed-by: Petr Mladek Signed-off-by: John Ogness Link: https://lore.kernel.org/r/20220506213324.470461-1-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c index 489d192..03ff634 100644 --- a/drivers/tty/serial/msm_serial.c +++ b/drivers/tty/serial/msm_serial.c @@ -1588,6 +1588,7 @@ static inline struct uart_port *msm_get_port_from_line(unsigned int line) static void __msm_console_write(struct uart_port *port, const char *s, unsigned int count, bool is_uartdm) { + unsigned long flags; int i; int num_newlines = 0; bool replaced = false; @@ -1605,6 +1606,8 @@ static void __msm_console_write(struct uart_port *port, const char *s, num_newlines++; count += num_newlines; + local_irq_save(flags); + if (port->sysrq) locked = 0; else if (oops_in_progress) @@ -1650,6 +1653,8 @@ static void __msm_console_write(struct uart_port *port, const char *s, if (locked) spin_unlock(&port->lock); + + local_irq_restore(flags); } static void msm_console_write(struct console *co, const char *s,