From 298e8488646e25e62b3879b88958cf0672b5acac Mon Sep 17 00:00:00 2001
From: Michael Pratt <mpratt@google.com>
Date: Fri, 8 Sep 2023 17:59:02 -0400
Subject: [PATCH] runtime: don't clear procid on netbsd

This is a partial revert of CL 526118.

NetBSD uses mp.procid in locking (semawake). unminit is called
surprisingly early in mexit, and there is definitely locking after that
point, so it isn't safe to clear procid so early.

Fixes #62524.
Fixes #62531.

Change-Id: Iefbef63e84fc0395e255970a301401e1187a910d
Reviewed-on: https://go-review.googlesource.com/c/go/+/527057
Reviewed-by: Benny Siegert <bsiegert@gmail.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
---
 src/runtime/os_netbsd.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/runtime/os_netbsd.go b/src/runtime/os_netbsd.go
index c5d7b4b978..7cbba48194 100644
--- a/src/runtime/os_netbsd.go
+++ b/src/runtime/os_netbsd.go
@@ -316,7 +316,8 @@ func minit() {
 //go:nosplit
 func unminit() {
 	unminitSignals()
-	getg().m.procid = 0
+	// Don't clear procid, it is used by locking (semawake), and locking
+	// must continue working after unminit.
 }
 
 // Called from exitm, but not from drop, to undo the effect of thread-owned
-- 
2.50.0