From: Mandeep Singh Baines <msb@chromium.org>
Date: Tue, 5 Feb 2013 22:55:38 +0000 (-0800)
Subject: CHROMIUM: sysrq-x: killall chrome process not just first one
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=e082d3bf92d2ac86a9c089a8e8db696b6f63edae;p=people%2Faperard%2Flinux-chromebook.git

CHROMIUM: sysrq-x: killall chrome process not just first one

Currently, sysrq-x just kills the first chrome process it finds.
We've seen in at least one occassion where there may be a stale
chrome process from a previous session. The fix is to kill all
processes we find that meet our criteria.

I also modified the printk to print the pid of the process
that is killed. Previously we were printing the pid of
session_manager which is not as useful.

BUG=chrome-os-partner:17522
TEST=manual (debugging feature):
 hold down alt-volup then x - chrome should crash
 repeat immediately afterward - session should restart
 repeat and machine should reboot

2013-02-05T13:28:37.425355-08:00 localhost crash_reporter[2829]: Received crash notification for chrome[963] sig 6 (ignoring - chrome crash)
2013-02-05T13:28:37.557482-08:00 localhost session_manager: [0205/132837:INFO:session_manager_service.cc(523)] Handling child process exit: 963
2013-02-05T13:28:37.557537-08:00 localhost session_manager: [0205/132837:INFO:session_manager_service.cc(525)]   Exited with signal 6

Change-Id: Id039df7386cf7cccf42e0861bc2ab6f653147605
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/42658
Reviewed-by: Sonny Rao <sonnyrao@chromium.org>
Reviewed-by: Sameer Nanda <snanda@chromium.org>
---

diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 460998928668b..357a02d4545f3 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -407,33 +407,18 @@ static void sysrq_x_cros_signal_process(char *comm, char *parent, int sig)
 
 	read_lock(&tasklist_lock);
 	for_each_process(p) {
-		if (p->flags & PF_KTHREAD)
+		if (p->flags & (PF_KTHREAD | PF_EXITING))
 			continue;
 		if (is_global_init(p))
 			continue;
+		if (strncmp(p->comm, comm, TASK_COMM_LEN))
+			continue;
+		if (parent && strncmp(p->parent->comm, parent, TASK_COMM_LEN))
+			continue;
 
-		if (!strncmp(p->comm, comm, TASK_COMM_LEN)) {
-			if (!parent) {
-				printk(KERN_INFO
-				       "%s: signal %d %s pid %u tgid %u\n",
-				       __func__, sig, comm, p->pid, p->tgid);
-				do_send_sig_info(sig, SEND_SIG_FORCED, p,
-						 true);
-				break;
-			} else if (p->parent &&
-				   !strncmp(p->parent->comm, parent,
-					  TASK_COMM_LEN)) {
-				printk(KERN_INFO
-				       "%s: signal %d %s with parent %s "
-				       "pid %u tgid %u\n",
-				       __func__, sig,
-				       comm, parent, p->parent->pid,
-				       p->parent->tgid);
-				do_send_sig_info(sig, SEND_SIG_FORCED, p,
-						 true);
-				break;
-			}
-		}
+		printk(KERN_INFO "%s: signal %d %s pid %u tgid %u\n",
+		       __func__, sig, comm, p->pid, p->tgid);
+		do_send_sig_info(sig, SEND_SIG_FORCED, p, true);
 	}
 	read_unlock(&tasklist_lock);
 }