[PATCH] dirvers: scmi: poll again when transfer reach timeout

jack21 jackhuang021 at gmail.com
Thu Jan 23 00:33:24 PST 2025


From: Huangjie <huangjie1663 at phytium.com.cn>

spin_until_cond() not really hold a spin lock, possible timeout may occur
in preemption kernel when preempted after spin_until_cond().

We check status again when reach timeout is reached to prevent incorrect
jugement of timeout.

Signed-off-by: Huangjie <huangjie1663 at phytium.com.cn>
---
 drivers/firmware/arm_scmi/driver.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 1b5fb2c4ce86..10b049fe5fd0 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -1246,7 +1246,8 @@ static int scmi_wait_for_reply(struct device *dev, const struct scmi_desc *desc,
 
 			spin_until_cond(scmi_xfer_done_no_timeout(cinfo,
 								  xfer, stop));
-			if (ktime_after(ktime_get(), stop)) {
+			if (ktime_after(ktime_get(), stop) &&
+			    !info->desc->ops->poll_done(cinfo, xfer)) {
 				dev_err(dev,
 					"timed out in resp(caller: %pS) - polling\n",
 					(void *)_RET_IP_);
-- 
2.34.1




More information about the linux-arm-kernel mailing list