This is a note to let you know that I've just added the patch titled firmware: arm_scmi: Reject clear channel request on A2P to the 6.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: firmware-arm_scmi-reject-clear-channel-request-on-a2.patch and it can be found in the queue-6.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 4ef08650bf5ac8db2395c00a2dc6e6bd4ceeb702 Author: Cristian Marussi <cristian.marussi@xxxxxxx> Date: Mon Oct 21 18:15:44 2024 +0100 firmware: arm_scmi: Reject clear channel request on A2P [ Upstream commit a0a18e91eb3a6ef75a6de69dc00f206b913e3848 ] The clear channel transport operation is supposed to be called exclusively on the P2A channel from the agent, since it relinquishes the ownership of the channel to the platform, after this latter has initiated some sort of P2A communication. Make sure that, if it is ever called on a A2P, is logged and ignored. Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx> Reviewed-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx> Message-Id: <20241021171544.2579551-1-cristian.marussi@xxxxxxx> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 4b8c5250cdb57..cd30499b2555f 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -163,6 +163,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); * used to initialize this channel * @dev: Reference to device in the SCMI hierarchy corresponding to this * channel + * @is_p2a: A flag to identify a channel as P2A (RX) * @rx_timeout_ms: The configured RX timeout in milliseconds. * @handle: Pointer to SCMI entity handle * @no_completion_irq: Flag to indicate that this channel has no completion @@ -174,6 +175,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); struct scmi_chan_info { int id; struct device *dev; + bool is_p2a; unsigned int rx_timeout_ms; struct scmi_handle *handle; bool no_completion_irq; diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index dc09f2d755f41..80b44bd1a3f3e 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -1034,6 +1034,11 @@ static inline void scmi_xfer_command_release(struct scmi_info *info, static inline void scmi_clear_channel(struct scmi_info *info, struct scmi_chan_info *cinfo) { + if (!cinfo->is_p2a) { + dev_warn(cinfo->dev, "Invalid clear on A2P channel !\n"); + return; + } + if (info->desc->ops->clear_channel) info->desc->ops->clear_channel(cinfo); } @@ -2614,6 +2619,7 @@ static int scmi_chan_setup(struct scmi_info *info, struct device_node *of_node, if (!cinfo) return -ENOMEM; + cinfo->is_p2a = !tx; cinfo->rx_timeout_ms = info->desc->max_rx_timeout_ms; /* Create a unique name for this transport device */