From: Erik Jacobson <ejacobso@redhat.com>
Subject: Re: [RHEL5 Patch] BZ 218882 process connector exessive unaligned access
Date: Wed, 13 Dec 2006 01:10:49 -0500
Bugzilla: 218882
Message-Id: <20061213061049.GA21503@redhat.com>
Changelog: connector: exessive unaligned access


Andrew took my change in to -mm, but asked a good question on something
we hadn't considered.

So I've made a new patch.  The version here is built and tested against
rhel5 rc snapshot2.  It's virtually the same as the community, this time
with one piece of fuzz being the only difference.

This fixed ia64 just like my original patch.  I also verified x86_64
again to be sure it didn't introduce trouble there.

I suspect now that Andrew will take this patch and not my original.
If anybody sees trouble with it (I've never used put_unaligned before),
please let me know.


Index: linux/drivers/connector/cn_proc.c
===================================================================
--- linux.orig/drivers/connector/cn_proc.c
+++ linux/drivers/connector/cn_proc.c
@@ -28,6 +28,7 @@
 #include <linux/init.h>
 #include <linux/connector.h>
 #include <asm/atomic.h>
+#include <asm/unaligned.h>
 
 #include <linux/cn_proc.h>
 
@@ -60,7 +61,7 @@ void proc_fork_connector(struct task_str
 	ev = (struct proc_event*)msg->data;
 	get_seq(&msg->seq, &ev->cpu);
 	ktime_get_ts(&ts); /* get high res monotonic timestamp */
-	ev->timestamp_ns = timespec_to_ns(&ts);
+	put_unaligned(timespec_to_ns(&ts), (__u64 *) &ev->timestamp_ns);
 	ev->what = PROC_EVENT_FORK;
 	ev->event_data.fork.parent_pid = task->parent->pid;
 	ev->event_data.fork.parent_tgid = task->parent->tgid;
@@ -88,7 +89,7 @@ void proc_exec_connector(struct task_str
 	ev = (struct proc_event*)msg->data;
 	get_seq(&msg->seq, &ev->cpu);
 	ktime_get_ts(&ts); /* get high res monotonic timestamp */
-	ev->timestamp_ns = timespec_to_ns(&ts);
+	put_unaligned(timespec_to_ns(&ts), (__u64 *) &ev->timestamp_ns);
 	ev->what = PROC_EVENT_EXEC;
 	ev->event_data.exec.process_pid = task->pid;
 	ev->event_data.exec.process_tgid = task->tgid;
@@ -124,7 +125,7 @@ void proc_id_connector(struct task_struc
 	     	return;
 	get_seq(&msg->seq, &ev->cpu);
 	ktime_get_ts(&ts); /* get high res monotonic timestamp */
-	ev->timestamp_ns = timespec_to_ns(&ts);
+	put_unaligned(timespec_to_ns(&ts), (__u64 *) &ev->timestamp_ns);
 
 	memcpy(&msg->id, &cn_proc_event_id, sizeof(msg->id));
 	msg->ack = 0; /* not used */
@@ -146,7 +147,7 @@ void proc_exit_connector(struct task_str
 	ev = (struct proc_event*)msg->data;
 	get_seq(&msg->seq, &ev->cpu);
 	ktime_get_ts(&ts); /* get high res monotonic timestamp */
-	ev->timestamp_ns = timespec_to_ns(&ts);
+	put_unaligned(timespec_to_ns(&ts), (__u64 *) &ev->timestamp_ns);
 	ev->what = PROC_EVENT_EXIT;
 	ev->event_data.exit.process_pid = task->pid;
 	ev->event_data.exit.process_tgid = task->tgid;
@@ -181,7 +182,7 @@ static void cn_proc_ack(int err, int rcv
 	ev = (struct proc_event*)msg->data;
 	msg->seq = rcvd_seq;
 	ktime_get_ts(&ts); /* get high res monotonic timestamp */
-	ev->timestamp_ns = timespec_to_ns(&ts);
+	put_unaligned(timespec_to_ns(&ts), (__u64 *) &ev->timestamp_ns);
 	ev->cpu = -1;
 	ev->what = PROC_EVENT_NONE;
 	ev->event_data.ack.err = err;