On Fri, 2 Jun 2023, Bernhard Seibold wrote:

Currently, the error interrupt is never acknowledged, so once active it will stay active indefinitely, causing the handler to be called in an infinite loop.

Fixes: 2f0fc4159a6a ("SERIAL: Lantiq: Add driver for MIPS Lantiq SOCs.") Cc: stable@vger.kernel.org Signed-off-by: Bernhard Seibold mail@bernhard-seibold.de

---

drivers/tty/serial/lantiq.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c index a58e9277dfad..f1387f1024db 100644 --- a/drivers/tty/serial/lantiq.c +++ b/drivers/tty/serial/lantiq.c @@ -250,6 +250,7 @@ lqasc_err_int(int irq, void *_port) struct ltq_uart_port *ltq_port = to_ltq_uart_port(port); spin_lock_irqsave(&ltq_port->lock, flags);

• __raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR); /* clear any pending interrupts */ asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE | ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);

Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com

This has been there since the beginning, it is a bit odd if nobody has hit this before now.

This is a note to let you know that I've just added the patch titled

serial: lantiq: add missing interrupt ack

to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-linus branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the next -rc kernel release.

If you have any questions about this process, please let me know.

From 306320034e8fbe7ee1cc4f5269c55658b4612048 Mon Sep 17 00:00:00 2001 From: Bernhard Seibold mail@bernhard-seibold.de Date: Fri, 2 Jun 2023 15:30:29 +0200 Subject: serial: lantiq: add missing interrupt ack MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

Currently, the error interrupt is never acknowledged, so once active it will stay active indefinitely, causing the handler to be called in an infinite loop.

Fixes: 2f0fc4159a6a ("SERIAL: Lantiq: Add driver for MIPS Lantiq SOCs.") Cc: stable@vger.kernel.org Signed-off-by: Bernhard Seibold mail@bernhard-seibold.de Reviewed-by: Ilpo Järvinen ilpo.jarvinen@linux.intel.com Message-ID: 20230602133029.546-1-mail@bernhard-seibold.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/lantiq.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c index a58e9277dfad..f1387f1024db 100644 --- a/drivers/tty/serial/lantiq.c +++ b/drivers/tty/serial/lantiq.c @@ -250,6 +250,7 @@ lqasc_err_int(int irq, void *_port) struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);

spin_lock_irqsave(&ltq_port->lock, flags); + __raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR); /* clear any pending interrupts */ asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE | ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);