Fix bug [57945b574a6df0332efc4ac96b066f7c347b28f7|57945b574a]: lock in forking process under heavy multithreading. Thanks to Joe Mistachkin for the implementation of the fix, and Gustaf Neumann for the original report and testing the fix.

1 files changed, 9 insertions, 1 deletions

diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index b2bea45..17fdc95 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -1334,6 +1334,9 @@ NotifierThreadProc(
 static void
 AtForkPrepare(void)
 {
+    Tcl_MutexLock(&notifierMutex);
+    TclpMasterLock();
+    TclpMutexLock();
 }
 
 /*
@@ -1355,6 +1358,9 @@ AtForkPrepare(void)
 static void
 AtForkParent(void)
 {
+    TclpMutexUnlock();
+    TclpMasterUnlock();
+    Tcl_MutexUnlock(&notifierMutex);
 }
 
 /*
@@ -1376,7 +1382,9 @@ AtForkParent(void)
 static void
 AtForkChild(void)
 {
-    Tcl_MutexFinalize(&notifierMutex);
+    TclpMutexUnlock();
+    TclpMasterUnlock();
+    TclMutexUnlockAndFinalize(&notifierMutex);
     Tcl_InitNotifier();
 }
 #endif /* HAVE_PTHREAD_ATFORK */