From f40c1eab921e75a14767693b6f7114cb08bbaf8b Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 3 Oct 2025 17:49:53 +0000
Subject: [PATCH] Fix ticker stop race condition by clearing period before
 removing timer

Co-authored-by: cataggar <87583576+cataggar@users.noreply.github.com>
---
 src/runtime/time_go122.go | 5 +++++
 src/runtime/time_go123.go | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/src/runtime/time_go122.go b/src/runtime/time_go122.go
index 2693555cf5..57481a6e71 100644
--- a/src/runtime/time_go122.go
+++ b/src/runtime/time_go122.go
@@ -53,6 +53,11 @@ func startTimer(tim *timer) {
 
 //go:linkname stopTimer time.stopTimer
 func stopTimer(tim *timer) bool {
+	// Set period to 0 to prevent the timer from being re-added to the queue
+	// if the callback is currently running. This must be done before removing
+	// the timer to avoid a race condition where the callback re-adds the timer
+	// after it's been removed.
+	tim.period = 0
 	return removeTimer(tim) != nil
 }
 
diff --git a/src/runtime/time_go123.go b/src/runtime/time_go123.go
index e39da74488..9ea36e6487 100644
--- a/src/runtime/time_go123.go
+++ b/src/runtime/time_go123.go
@@ -52,6 +52,11 @@ func newTimer(when, period int64, f func(arg any, seq uintptr, delta int64), arg
 
 //go:linkname stopTimer time.stopTimer
 func stopTimer(tim *timeTimer) bool {
+	// Set period to 0 to prevent the timer from being re-added to the queue
+	// if the callback is currently running. This must be done before removing
+	// the timer to avoid a race condition where the callback re-adds the timer
+	// after it's been removed.
+	tim.timer.period = 0
 	return removeTimer(&tim.timer) != nil
 }