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Date: Fri, 18 Mar 2011 23:56:43 +0100
From: David Sterba <dave@jikos.cz>
To: Chris Mason <chris.mason@oracle.com>
Cc: David Sterba <dsterba@suse.cz>, linux-btrfs <linux-btrfs@vger.kernel.org>,
	"adrien.dessemond" <adrien.dessemond@gmail.com>
Subject: Re: [PATCH] btrfs: properly access unaligned checksum buffer
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diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index e1aa8d6..80a6830 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -29,6 +29,7 @@
 #include <linux/crc32c.h>
 #include <linux/slab.h>
 #include <linux/migrate.h>
+#include <asm/unaligned.h>
 #include "compat.h"
 #include "ctree.h"
 #include "disk-io.h"
@@ -198,7 +199,7 @@ u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len)

 void btrfs_csum_final(u32 crc, char *result)
 {
-       *(__le32 *)result = ~cpu_to_le32(crc);
+       put_unaligned_le32(~crc, result);
 }

 /*