[release-branch.go1.20] runtime: set raceignore to zero when starting a new goroutine
When reusing a g struct the runtime did not reset
g.raceignore. Initialize raceignore to zero when initially
setting racectx.
A goroutine can end with a non-zero raceignore if it exits
after calling runtime.RaceDisable without a matching
runtime.RaceEnable. If that goroutine's g is later reused
the race detector is in a weird state: the underlying
g.racectx is active, yet g.raceignore is non-zero, and
raceacquire/racerelease which check g.raceignore become
no-ops. This causes the race detector to report races when
there are none.
For #60934
Fixes #60949
Change-Id: Ib8e412f11badbaf69a480f03740da70891f4093f
Reviewed-on: https://go-review.googlesource.com/c/go/+/505055
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
(cherry picked from commit 48dbb6227acf3ebc8ac21924567aa2b6d5064915)
Reviewed-on: https://go-review.googlesource.com/c/go/+/505676
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index bf2a33e..96908fc 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -4351,6 +4351,7 @@
pp.goidcache++
if raceenabled {
newg.racectx = racegostart(callerpc)
+ newg.raceignore = 0
if newg.labels != nil {
// See note in proflabel.go on labelSync's role in synchronizing
// with the reads in the signal handler.
diff --git a/src/runtime/race/testdata/mop_test.go b/src/runtime/race/testdata/mop_test.go
index 0d79091..4a9ce26 100644
--- a/src/runtime/race/testdata/mop_test.go
+++ b/src/runtime/race/testdata/mop_test.go
@@ -2092,3 +2092,40 @@
<-done
}
}
+
+func TestNoRaceIssue60934(t *testing.T) {
+ // Test that runtime.RaceDisable state doesn't accidentally get applied to
+ // new goroutines.
+
+ // Create several goroutines that end after calling runtime.RaceDisable.
+ var wg sync.WaitGroup
+ ready := make(chan struct{})
+ wg.Add(32)
+ for i := 0; i < 32; i++ {
+ go func() {
+ <-ready // ensure we have multiple goroutines running at the same time
+ runtime.RaceDisable()
+ wg.Done()
+ }()
+ }
+ close(ready)
+ wg.Wait()
+
+ // Make sure race detector still works. If the runtime.RaceDisable state
+ // leaks, the happens-before edges here will be ignored and a race on x will
+ // be reported.
+ var x int
+ ch := make(chan struct{}, 0)
+ wg.Add(2)
+ go func() {
+ x = 1
+ ch <- struct{}{}
+ wg.Done()
+ }()
+ go func() {
+ <-ch
+ _ = x
+ wg.Done()
+ }()
+ wg.Wait()
+}
