The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x 306320034e8fbe7ee1cc4f5269c55658b4612048 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023061831-detention-overtime-783b@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

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: [PATCH] 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

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);