The patch below does not apply to the 6.6-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-6.6.y git checkout FETCH_HEAD git cherry-pick -x 23f5f5debcaac1399cfeacec215278bf6dbc1d11 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024102142-pristine-mayday-9998@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

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

From 23f5f5debcaac1399cfeacec215278bf6dbc1d11 Mon Sep 17 00:00:00 2001 From: Johan Hovold johan+linaro@kernel.org Date: Wed, 9 Oct 2024 16:51:04 +0200 Subject: [PATCH] serial: qcom-geni: fix shutdown race

A commit adding back the stopping of tx on port shutdown failed to add back the locking which had also been removed by commit e83766334f96 ("tty: serial: qcom_geni_serial: No need to stop tx/rx on UART shutdown").

Holding the port lock is needed to serialise against the console code, which may update the interrupt enable register and access the port state.

Fixes: d8aca2f96813 ("tty: serial: qcom-geni-serial: stop operations in progress at shutdown") Fixes: 947cc4ecc06c ("serial: qcom-geni: fix soft lockup on sw flow control and suspend") Cc: stable@vger.kernel.org # 6.3 Reviewed-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Signed-off-by: Johan Hovold johan+linaro@kernel.org Reviewed-by: Douglas Anderson dianders@chromium.org Link: https://lore.kernel.org/r/20241009145110.16847-4-johan+linaro@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c index 2e4a5361f137..87cd974b76bf 100644 --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -1114,10 +1114,12 @@ static void qcom_geni_serial_shutdown(struct uart_port *uport) { disable_irq(uport->irq);

+ uart_port_lock_irq(uport); qcom_geni_serial_stop_tx(uport); qcom_geni_serial_stop_rx(uport);

qcom_geni_serial_cancel_tx_cmd(uport); + uart_port_unlock_irq(uport); }

static void qcom_geni_serial_flush_buffer(struct uart_port *uport)