Re: 1352 NUL bytes at the end of a page? (was Re: Assertion `s && s->tree' failed: The saga continues.)

Steven Cole
2004-05-19T10:54:19Z

On Tuesday 18 May 2004 08:38 am, Linus Torvalds wrote:
>
> On Mon, 17 May 2004, Steven Cole wrote:
> >
> > No problems, and with PREEMPT of course.
>
> Ok. Good. It's a small data-set, but the bug made sense, and so did the
> fix.

Perhaps a final note on this: I did more testing on reiserfs overnight with
Chris' patch, and it survived eleven pulls and unpulls with no failures.

>
> > > If you see a failure on ext3, please try to analyze the corruption pattern
> > > again. It might be something different.
> >
> > So, I take it that I should revert that one-liner if I want to get any failure data?
> > With it, ext3 was pretty solid for this testing.
>
> Yes. That one-liner is bogus. It was a good way to test a hypothesis for
> the common case of a filesystem that uses the block_write_full_page thing
> (and reiser is one of the few that doesn't), but it wasn't the real fix.
> The reiser patch was the real fix for the problem on reiser, but ext3
> should have been ok already. It uses (through a lot of other functions)
> generic_file_aio_write_nolock() as the real write engine, and that one
> calls "commit_write()" with the page lock held.
>
> Linus

I also tested ext3 more extensively (10 pulls/unpulls) and could not repeat
the alleged failure on ext3. That was with akpm's one-liner backed out.

Steven