From: Eric Sandeen <sandeen@redhat.com>
Date: Fri, 1 Oct 2010 20:08:14 -0400
Subject: [fs] jbd2: properly align sized slab caches
Message-id: <4CA63FAE.7030604@redhat.com>
Patchwork-id: 28563
O-Subject: [PATCH RHEL5.6] jbd2: properly align sized slab caches
Bugzilla: 638961
RH-Acked-by: Josef Bacik <josef@redhat.com>
RH-Acked-by: Larry Woodman <lwoodman@redhat.com>

This is for bug
638961 - kernel BUG in jbd2_alloc at fs/jbd2/journal.c:2075!

a bit of a brown paper bag, the alignment got lost in the backport
and a misaligned slab cache is now caught with a BUG_ON() in jbd2,
more apparent on ppc64.

This fixes it for me, and matches what's upstream from:

commit d2eecb03936878ec574ade5532fa83df7d75dde7
Author: Theodore Ts'o <tytso@mit.edu>
Date:   Mon Dec 7 10:36:20 2009 -0500

    ext4: Use slab allocator for sub-page sized allocations

Thanks,
-Eric


diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index aa78637..de6e2d2 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2031,7 +2031,7 @@ static int jbd2_journal_create_slab(size_t size)
 
 	slab_size = 1 << (i+10);
 	jbd2_slab[i] = kmem_cache_create(jbd2_slab_names[i], slab_size,
-					 0, 0, NULL, NULL);
+					 slab_size, 0, NULL, NULL);
 	up(&jbd2_slab_create_sem);
 	if (!jbd2_slab[i]) {
 		printk(KERN_EMERG "JBD2: no memory for jbd2_slab cache\n");