linux-ext4.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Theodore Tso <tytso@mit.edu>
To: Valerie Aurora <vaurora@redhat.com>
Cc: linux-ext4@vger.kernel.org, Eric Sandeen <sandeen@redhat.com>,
	Ric Wheeler <rwheeler@redhat.com>
Subject: Re: Fix device too big bug in mainline?
Date: Sat, 1 Aug 2009 23:49:47 -0400	[thread overview]
Message-ID: <20090802034947.GA15828@mit.edu> (raw)
In-Reply-To: <20090802022209.GC8680@mit.edu>

On Sat, Aug 01, 2009 at 10:22:09PM -0400, Theodore Tso wrote:
> temporary checkin; about to do checksum conversion
> 
> From: Valerie Aurora Henson <vaurora@redhat.com>
> 
> Signed-off-by: Valerie Aurora Henson <vaurora@redhat.com>

BTW, while I was painstakingly picking apart this patch, separating it
into its constiuent pieces, I found the following bug in it:

diff --git a/e2fsck/super.c b/e2fsck/super.c
index c269b0e..a1fb878 100644
--- a/e2fsck/super.c
+++ b/e2fsck/super.c
	....
 			if (fix_problem(ctx, PR_0_GDT_UNINIT, &pctx)) {
-				gd->bg_flags &= ~(EXT2_BG_BLOCK_UNINIT |
-						  EXT2_BG_INODE_UNINIT);
-				gd->bg_itable_unused = 0;
+				ext2fs_bg_flag_clear (fs, i, EXT2_BG_BLOCK_UNINIT);
+				ext2fs_bg_flag_clear (fs, i, EXT2_BG_INODE_UNINIT);
 				should_be = 1;
 			}


This patch hunk (buried deep within the 800+ lines of the "temporary
checkin; about to do checksum conversion" patch) removed this line:

				gd->bg_itable_unused = 0;

... but failed to replace it with this line:

				ext2fs_bg_itable_unused_set(fs, i, 0);

This is *why* I insist on auditable patches, and why I can't just
blindly merge the 64-bit branch.  When multiple semantic changes are
mushed up all together in one gigundo patch, it's really easy to miss
omissions like this, and since we don't have a regression test to test
this specific repair, we would have never noticed.

And no, it's no fun for me to be picking through this patch set at on
a Saturday evening on a Summer evening; I'd rather be in Lenox,
enjoying a concert at Tanglewood.  But someone has got to do it...

	     	      		     	     	     - Ted


  reply	other threads:[~2009-08-02  3:49 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-30 21:53 Fix device too big bug in mainline? Valerie Aurora
2009-08-02  0:28 ` Theodore Tso
2009-08-02  2:22   ` Theodore Tso
2009-08-02  3:49     ` Theodore Tso [this message]
2009-08-03 20:11     ` Valerie Aurora
2009-08-03 20:27     ` spatch for 64-bit e2fsprogs (was Re: Fix device too big bug in mainline?) Valerie Aurora
2009-08-03 22:56       ` Valerie Aurora
2009-08-04  6:40       ` Julia Lawall
2009-08-04 14:48       ` Theodore Tso
2009-08-04 18:18         ` Valerie Aurora
2009-08-04 19:24           ` Andreas Dilger
2009-08-04 19:58             ` Valerie Aurora
2009-08-04 20:32           ` Theodore Tso
2009-08-04 18:28     ` Fix device too big bug in mainline? Valerie Aurora
2009-08-04 20:41       ` Theodore Tso
2009-08-04 21:29         ` Valerie Aurora
2009-08-04 22:12           ` Theodore Tso
2009-08-04 23:56       ` Theodore Tso
2009-08-03 18:04   ` Valerie Aurora

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20090802034947.GA15828@mit.edu \
    --to=tytso@mit.edu \
    --cc=linux-ext4@vger.kernel.org \
    --cc=rwheeler@redhat.com \
    --cc=sandeen@redhat.com \
    --cc=vaurora@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).