Message ID | c0035ba4d796786514d8efe3d0cc04ea6d88e330.1376651114.git.viresh.kumar@linaro.org |
---|---|
State | New |
Headers | show |
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c index 376079b..275e3e0 100644 --- a/drivers/tty/serial/samsung.c +++ b/drivers/tty/serial/samsung.c @@ -249,6 +249,8 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id) ufcon |= S3C2410_UFCON_RESETRX; wr_regl(port, S3C2410_UFCON, ufcon); rx_enabled(port) = 1; + spin_unlock_irqrestore(&port->lock, + flags); goto out; } continue; @@ -297,10 +299,11 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id) ignore_char: continue; } + + spin_unlock_irqrestore(&port->lock, flags); tty_flip_buffer_push(&port->state->port); out: - spin_unlock_irqrestore(&port->lock, flags); return IRQ_HANDLED; }
The -rt patch triggers a lockdep warning for serial drivers if tty_flip_buffer_push() is called with uart_port->lock locked. This never shows up on UP kernels. Release the port lock before calling tty_flip_buffer_push() and reacquire it after the call. Similar stuff was already done for few other drivers in the past, like: commit 2389b272168ceec056ca1d8a870a97fa9c26e11a Author: Thomas Gleixner <tglx@linutronix.de> Date: Tue May 29 21:53:50 2007 +0100 [ARM] 4417/1: Serial: Fix AMBA drivers locking Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- drivers/tty/serial/samsung.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)