Re: [PATCH 1/2] ext4: journal all modifications in ext4_xattr_set_handle

[Theodore Tso <tytso@mit.edu>]

On Fri, Nov 06, 2009 at 05:22:51PM -0700, Andreas Dilger wrote:
> On 2009-11-06, at 15:35, Eric Sandeen wrote:
>> Eric Sandeen wrote:
>>> ext4_xattr_set_handle() was modifying s_inode_size outside
>>> of journaling constraints; this is one of the accesses that
>>> was causing the crc errors in journal replay as seen in
>>> kernel.org bugzilla #14354.
>>
>> Oh, and for those who haven't been following the bug, big
>> thanks to Chris Mason for helping to look into this and coming
>> up with the debugging patch that made it obvious...
>
> It would be great, IMHO, to have this debugging patch submitted to
> the kernel also, and enabled under a CONFIG option.

The debugging patch is only safe when the file system's block size ==
page size.  I suppose we could leave a warning in Kconfig that the
debugging option is only safe to be used when all of the file systems
in the system have a 4k (or whatever the page size happens to be)
block size, but it's probably better to clean up the patch so that
it's only enabled on a mount option, and then only if the file system
block size is the same as the page size.

> I'd also be interested to see the "write shadow buffer to journal"
> one-line patch that was discussed in the bug.

Which patch are you referring to?

					- Ted