Does this patch eliminate the problem? Unfortunately I can not generate this error again because after re-formatting the memory (mkfs.nilfs2) the problem disappeared. Łukasz Wójcicki Dnia 2010-07-07, śro o godzinie 15:02 +0900, Ryusuke Konishi pisze: > Hi, > > On Tue, 06 Jul 2010 11:02:41 +0200, Łukasz_Wójcicki wrote: > > I'am using kernel 2.6.20 with nilf_utils-2-0-18 and nilfs kernel module > > 2-0-20 . > > > > <1>Unable to handle kernel NULL pointer dereference at virtual address > > 00000000 > > <1>pgd = c4eb0000 > > <1>[00000000] *pgd=c4e2d031, *pte=00000000, *ppte=00000000 > > <4>Internal error: Oops: 17 [#1] > > <4>Modules linked in: > > <4>CPU: 0 > > <4>PC is at nilfs_btree_lookup_dirty_buffers+0x10c/0x1ec > > <4>LR is at 0xc4c99b24 > <snip> > > Could you try the following patch to narrow down the cause? > > There is a function lacking range check in the btree code. This patch > will catch the defect if the oops comes from a range error. > > I'm now reviewing the btree code to find out root cause of the range > error. > > Thanks, > Ryusuke Konishi > --- > > diff --git a/fs/btree.c b/fs/btree.c > index beb11fe..9622ff4 100644 > --- a/fs/btree.c > +++ b/fs/btree.c > @@ -2007,6 +2007,15 @@ static void nilfs_btree_add_dirty_buffer(struct nilfs_btree *btree, > node = (struct nilfs_btree_node *)bh->b_data; > key = nilfs_btree_node_get_key(node, 0); > level = nilfs_btree_node_get_level(node); > + if (level < NILFS_BTREE_LEVEL_NODE_MIN || > + level >= NILFS_BTREE_LEVEL_MAX) { > + dump_stack(); > + printk(KERN_CRIT > + "%s: invalid btree level: %d (ino=%lu)\n", __func__, > + level, NILFS_BMAP_I(&btree->bt_bmap)->vfs_inode.i_ino); > + return; > + } > + > list_for_each(head, &lists[level]) { > cbh = list_entry(head, struct buffer_head, b_assoc_buffers); > cnode = (struct nilfs_btree_node *)cbh->b_data; -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html