From: Gabriel Somlo gsomlo@gmail.com
[ Upstream commit 1307c5d33cce8a41dd77c2571e4df65a5b627feb ]
Since altera_uart_interrupt() may also be called from a poll timer in "serving_softirq" context, use spin_[lock_irqsave|unlock_irqrestore] variants, which are appropriate for both softirq and hardware interrupt contexts.
Fixes: 2f8b9c15cd88 ("altera_uart: Add support for polling mode (IRQ-less)") Signed-off-by: Gabriel Somlo gsomlo@gmail.com Link: https://lore.kernel.org/r/20221122200426.888349-1-gsomlo@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/altera_uart.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c index 6e08fa11ceea..91799c420e25 100644 --- a/drivers/tty/serial/altera_uart.c +++ b/drivers/tty/serial/altera_uart.c @@ -278,16 +278,17 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data) { struct uart_port *port = data; struct altera_uart *pp = container_of(port, struct altera_uart, port); + unsigned long flags; unsigned int isr;
isr = altera_uart_readl(port, ALTERA_UART_STATUS_REG) & pp->imr;
- spin_lock(&port->lock); + spin_lock_irqsave(&port->lock, flags); if (isr & ALTERA_UART_STATUS_RRDY_MSK) altera_uart_rx_chars(port); if (isr & ALTERA_UART_STATUS_TRDY_MSK) altera_uart_tx_chars(port); - spin_unlock(&port->lock); + spin_unlock_irqrestore(&port->lock, flags);
return IRQ_RETVAL(isr); }