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Date: Tue, 21 Jan 2003 13:18:14 -0800
From: Andrew Morton <akpm@digeo.com>
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To: Hugh Dickins <hugh@veritas.com>
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Subject: Re: [PATCH] ext2 allocation failures
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Hugh Dickins wrote:
> 
> For almost a year (since 2.5.4) ext2_new_block has tended to set err
> 0 instead of -ENOSPC or -EIO.  This manifested variously (typically
> depends on what's stale in ext2_get_block's chain[4] array): sometimes
> __brelse free free buffer backtraces, sometimes release_pages oops,
> usually generic_make_request beyond end of device messages, followed
> by further ext2 errors.

ugh.

> [Insert lecture on dangers of using goto for unwind :-]

Actually, I rather don't like the practice of:

	*errp = -EFOO;
	<200 lines of code>
	if (something_bad)
		goto out;

And lo, both ext2_new_block() and ext3_new_block() have additional
bugs, due mainly to this dubious optimisation.

I'll change them to the very straightforward

	if (something_bad) {
		*errp = -EFOO;
		goto out;
	}


Thanks.