commit 16eda4e36cca0943b89505115c9ee0fee8d03d6d
author Janne Grunau <j@jannau.net> Tue Jun 14 09:09:09 2022 +0200
committer Tom Rini <trini@konsulko.com> Thu Jun 23 08:24:49 2022 -0400
tree 1a38e1211fc8ae7c89f91364d3067938c97e6808
parent 145a4ea157f8b1251fef036ac758e861dc15f61c

arm: apple: Increase RTKit timeouts

Timeouts are not expected to happen and are handled as fatal errors.
Increase all timeouts to 1 second as defensive measure to avoid relying
on the timing behaviour of certain firmware versions or configurations.

Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Mark Kettenis <kettenis@openbsd.org>
Tested-by: Mark Kettenis <kettenis@openbsd.org>

arch/arm/mach-apple/rtkit.c

diff --git a/arch/arm/mach-apple/rtkit.c b/arch/arm/mach-apple/rtkit.c
index da77718..a550b55 100644
--- a/arch/arm/mach-apple/rtkit.c
+++ b/arch/arm/mach-apple/rtkit.c
@@ -52,6 +52,8 @@
 #define APPLE_RTKIT_BUFFER_REQUEST_SIZE GENMASK(51, 44)
 #define APPLE_RTKIT_BUFFER_REQUEST_IOVA GENMASK(41, 0)
 
+#define TIMEOUT_1SEC_US 1000000
+
 struct apple_rtkit {
 	struct mbox_chan *chan;
 	void *cookie;
@@ -168,7 +170,7 @@
 		return ret;
 
 	/* Wait for protocol version negotiation message. */
-	ret = mbox_recv(rtk->chan, &msg, 10000);
+	ret = mbox_recv(rtk->chan, &msg, TIMEOUT_1SEC_US);
 	if (ret < 0)
 		return ret;
 
@@ -210,7 +212,7 @@
 
 wait_epmap:
 	/* Wait for endpoint map message. */
-	ret = mbox_recv(rtk->chan, &msg, 10000);
+	ret = mbox_recv(rtk->chan, &msg, TIMEOUT_1SEC_US);
 	if (ret < 0)
 		return ret;
 
@@ -275,7 +277,7 @@
 
 	pwrstate = APPLE_RTKIT_PWR_STATE_SLEEP;
 	while (pwrstate != APPLE_RTKIT_PWR_STATE_ON) {
-		ret = mbox_recv(rtk->chan, &msg, 100000);
+		ret = mbox_recv(rtk->chan, &msg, TIMEOUT_1SEC_US);
 		if (ret < 0)
 			return ret;
 
@@ -330,7 +332,7 @@
 	if (ret < 0)
 		return ret;
 
-	ret = mbox_recv(rtk->chan, &msg, 100000);
+	ret = mbox_recv(rtk->chan, &msg, TIMEOUT_1SEC_US);
 	if (ret < 0)
 		return ret;