From: Thomas Veerman <thomas@minix3.org>
Date: Tue, 4 Sep 2012 12:12:32 +0000 (+0000)
Subject: PM: don't deliver signals to VM
X-Git-Tag: v3.2.1~334
X-Git-Url: http://zhaoyanbai.com/repos//%22http:/www.isc.org/%22?a=commitdiff_plain;h=edefb7b35fae19813e45c3b036c3f50b04c324c3;p=minix.git

PM: don't deliver signals to VM
---

diff --git a/servers/pm/signal.c b/servers/pm/signal.c
index bb5ccd5a9..5e2901f72 100644
--- a/servers/pm/signal.c
+++ b/servers/pm/signal.c
@@ -530,6 +530,11 @@ int ksig;			/* non-zero means signal comes from kernel  */
 	if (proc_id == -1 && signo == SIGKILL &&
 		(rmp->mp_flags & PRIV_PROC)) continue;
 
+	/* Skip VM entirely as it might lead to a deadlock with its signal
+	 * manager if the manager page faults at the same time.
+	 */
+	if (rmp->mp_endpoint == VM_PROC_NR) continue;
+
 	/* Disallow lethal signals sent by user processes to sys processes. */
 	if (!ksig && SIGS_IS_LETHAL(signo) && (rmp->mp_flags & PRIV_PROC)) {
 	    error_code = EPERM;