[PATCH] ext3 -nobh option causes oops (2.6.17.7)

[PATCH] ext3 -nobh option causes oops (2.6.17.7)

[Badari Pulavarty]

Hi Andrew,

ext3 -nobh option causes kernel oops on files other than IFREG -
since the modification to them are journalled anyway and the
code expects to have buffer_head attached to it.

We need this patch for stable series also.

Thanks,
Badari

For files other than IFREG, nobh option doesn't make sense.
Modifications to them are journalled and needs buffer heads
to do that. Without this patch, we get kernel oops in page_buffers().

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>

Index: linux-2.6.17.7/fs/ext3/inode.c
===================================================================
--- linux-2.6.17.7.orig/fs/ext3/inode.c	2006-07-24 20:36:01.000000000 -0700
+++ linux-2.6.17.7/fs/ext3/inode.c	2006-07-27 13:26:13.000000000 -0700
@@ -1159,7 +1159,7 @@ retry:
 		ret = PTR_ERR(handle);
 		goto out;
 	}
-	if (test_opt(inode->i_sb, NOBH))
+	if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode))
 		ret = nobh_prepare_write(page, from, to, ext3_get_block);
 	else
 		ret = block_prepare_write(page, from, to, ext3_get_block);
@@ -1245,7 +1245,7 @@ static int ext3_writeback_commit_write(s
 	if (new_i_size > EXT3_I(inode)->i_disksize)
 		EXT3_I(inode)->i_disksize = new_i_size;
 
-	if (test_opt(inode->i_sb, NOBH))
+	if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode))
 		ret = nobh_commit_write(file, page, from, to);
 	else
 		ret = generic_commit_write(file, page, from, to);
@@ -1495,7 +1495,7 @@ static int ext3_writeback_writepage(stru
 		goto out_fail;
 	}
 
-	if (test_opt(inode->i_sb, NOBH))
+	if (test_opt(inode->i_sb, NOBH) && ext3_should_writeback_data(inode))
 		ret = nobh_writepage(page, ext3_get_block, wbc);
 	else
 		ret = block_write_full_page(page, ext3_get_block, wbc);

Re: [stable] [PATCH] ext3 -nobh option causes oops (2.6.17.7)

[Greg KH]

On Thu, Jul 27, 2006 at 01:42:41PM -0700, Badari Pulavarty wrote:
> Hi Andrew,
> 
> ext3 -nobh option causes kernel oops on files other than IFREG -
> since the modification to them are journalled anyway and the
> code expects to have buffer_head attached to it.
> 
> We need this patch for stable series also.
> 
> Thanks,
> Badari
> 
> For files other than IFREG, nobh option doesn't make sense.
> Modifications to them are journalled and needs buffer heads
> to do that. Without this patch, we get kernel oops in page_buffers().
> 
> Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>

Queued to -stable.

thanks,

greg k-h