CVS commit: src/sys/kern

[Kamil Rytarowski]

Module Name:    src
Committed By:   kamil
Date:           Tue Jun 18 23:53:55 UTC 2019

Modified Files:
        src/sys/kern: kern_exec.c kern_sig.c

Log Message:
Add support for KTR logs of SIGTRAP for TRAP_CHILD events

Previously it was disabled due to vfork(2) synchronization issues.
These problems are now gone.

While there, set l_vforkwaiting to false in posix_spawn. This is not very
needed but it does not make harm to keep it initialized explicitly.


To generate a diff of this commit:
cvs rdiff -u -r1.467 -r1.468 src/sys/kern/kern_exec.c
cvs rdiff -u -r1.360 -r1.361 src/sys/kern/kern_sig.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/kern/kern_exec.c
diff -u src/sys/kern/kern_exec.c:1.467 src/sys/kern/kern_exec.c:1.468
--- src/sys/kern/kern_exec.c:1.467	Thu Jun 13 20:20:18 2019
+++ src/sys/kern/kern_exec.c	Tue Jun 18 23:53:55 2019
@@ -1,4 +1,4 @@
-/*	$NetBSD: kern_exec.c,v 1.467 2019/06/13 20:20:18 kamil Exp $	*/
+/*	$NetBSD: kern_exec.c,v 1.468 2019/06/18 23:53:55 kamil Exp $	*/
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -59,7 +59,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.467 2019/06/13 20:20:18 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_exec.c,v 1.468 2019/06/18 23:53:55 kamil Exp $");
 
 #include "opt_exec.h"
 #include "opt_execfmt.h"
@@ -2470,6 +2470,7 @@ do_posix_spawn(struct lwp *l1, pid_t *pi
 	}
 
 	p2->p_lflag = 0;
+	l1->l_vforkwaiting = false;
 	p2->p_sflag = 0;
 	p2->p_slflag = 0;
 	p2->p_pptr = p1;

Index: src/sys/kern/kern_sig.c
diff -u src/sys/kern/kern_sig.c:1.360 src/sys/kern/kern_sig.c:1.361
--- src/sys/kern/kern_sig.c:1.360	Thu Jun 13 00:07:19 2019
+++ src/sys/kern/kern_sig.c	Tue Jun 18 23:53:55 2019
@@ -1,4 +1,4 @@
-/*	$NetBSD: kern_sig.c,v 1.360 2019/06/13 00:07:19 kamil Exp $	*/
+/*	$NetBSD: kern_sig.c,v 1.361 2019/06/18 23:53:55 kamil Exp $	*/
 
 /*-
  * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.360 2019/06/13 00:07:19 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.361 2019/06/18 23:53:55 kamil Exp $");
 
 #include "opt_ptrace.h"
 #include "opt_dtrace.h"
@@ -1621,9 +1621,12 @@ eventswitch(int code)
 
 	sigswitch(0, signo, false);
 
-	/* XXX: hangs for VFORK */
-	if (code == TRAP_CHLD)
-		return;
+	if (code == TRAP_CHLD) {
+		mutex_enter(proc_lock);
+		while (l->l_vforkwaiting)
+			cv_wait(&l->l_waitcv, proc_lock);
+		mutex_exit(proc_lock);
+	}
 
 	if (ktrpoint(KTR_PSIG)) {
 		if (p->p_emul->e_ktrpsig)