From: Amit Shah <amit.shah@redhat.com>
Date: Thu, 27 May 2010 07:54:40 +0000 (+0530)
Subject: virtio: console: Fix crash when port is unplugged and blocked for write
X-Git-Tag: v2.6.35-rc2~48^2
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=60e5e0b84045ce0f6ab07a02c7fcd6627b53d2d3

virtio: console: Fix crash when port is unplugged and blocked for write

When a program that has a virtio port opened and blocked for a write
operation, a port hot-unplug event will later led to a crash when
SIGTERM was sent to the program. Fix that.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index e3fb5296cf25..942a9826bd23 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -529,6 +529,10 @@ static bool will_write_block(struct port *port)
 {
 	bool ret;
 
+	if (!port->guest_connected) {
+		/* Port got hot-unplugged. Let's exit. */
+		return false;
+	}
 	if (!port->host_connected)
 		return true;