FAILED: patch "[PATCH] rtc: check if __rtc_read_time was successful" failed to apply to 4.9-stable tree

The patch below does not apply to the 4.9-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 <[email protected]>.

thanks,

greg k-h

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

From 915593a7a663b2ad08b895a5f3ba8b19d89d4ebf Mon Sep 17 00:00:00 2001
From: Tom Rix <[email protected]>
Date: Sat, 26 Mar 2022 12:42:36 -0700
Subject: [PATCH] rtc: check if __rtc_read_time was successful

Clang static analysis reports this issue interface.c:810:8: warning: Passed-by-value struct
argument contains uninitialized data

  now = rtc_tm_to_ktime(tm);
      ^~~~~~~~~~~~~~~~~~~

tm is set by a successful call to __rtc_read_time() but its return status is not checked. Check if it was successful before setting the enabled flag. Move the decl of err to function scope.

index d8e835798153..9edd662c69ac 100644
@@ -804,9 +804,13 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
 	struct timerqueue_node *next = timerqueue_getnext(&rtc->timerqueue);
 	struct rtc_time tm;
 	ktime_t now;
+	int err;
+
+	err = __rtc_read_time(rtc, &tm);
+	if (err)
+		return err;
 
 	timer->enabled = 1;
-	__rtc_read_time(rtc, &tm);
 	now = rtc_tm_to_ktime(tm);
 
 	/* Skip over expired timers */

@@ -820,7 +824,6 @@ static int rtc_timer_enqueue(struct rtc_device *rtc, struct rtc_timer *timer)
 	trace_rtc_timer_enqueue(timer);
 	if (!next || ktime_before(timer->node.expires, next->expires)) {
 		struct rtc_wkalrm alarm;
-		int err;
 
 		alarm.time = rtc_ktime_to_tm(timer->node.expires);
 		alarm.enabled = 1;