From: Ian Lance Taylor <iant@golang.org>
Date: Thu, 26 Mar 2020 16:13:11 +0000 (-0700)
Subject: runtime: lock mtxpoll in AIX netpollBreak
X-Git-Tag: go1.15beta1~731
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=78a45d8b4592dbd38057a2e9af83c9cf9d62ddc9;p=gostls13.git

runtime: lock mtxpoll in AIX netpollBreak

netpollBreak calls netpollwakeup, and netpollwakeup expects the mtxpoll
lock to be held, so that it has exclusive access to pendingUpdates.
Not acquiring the lock was a mistake in CL 171824. Fortunately it
rarely matters in practice.

Change-Id: I32962ec2575c846ef3d6a91a4d821b2ff02d983c
Reviewed-on: https://go-review.googlesource.com/c/go/+/225618
Reviewed-by: Michael Knyszek <mknyszek@google.com>
---

diff --git a/src/runtime/netpoll_aix.go b/src/runtime/netpoll_aix.go
index c936fbb70f..61becc247e 100644
--- a/src/runtime/netpoll_aix.go
+++ b/src/runtime/netpoll_aix.go
@@ -130,7 +130,9 @@ func netpollarm(pd *pollDesc, mode int) {
 
 // netpollBreak interrupts a poll.
 func netpollBreak() {
+	lock(&mtxpoll)
 	netpollwakeup()
+	unlock(&mtxpoll)
 }
 
 // netpoll checks for ready network connections.