Re: latest -git: A peculiar case of a stuck process (ext3/sched-related?)

From: Vegard Nossum
Date: Fri Jul 18 2008 - 13:05:48 EST


On Fri, Jul 18, 2008 at 3:00 PM, Duane Griffin <duaneg@xxxxxxxxx> wrote:
> 2008/7/18 Vegard Nossum <vegard.nossum@xxxxxxxxx>:
>> And the ext3_find_entry() corresponds to this line:
>>
>> for (; de < top; de = ext3_next_entry(de)) /* <--- HERE! */
>> if (ext3_match (namelen, name, de)) {
>> if (!ext3_check_dir_entry("ext3_find_entry",
>> dir, de, bh,
>> (block<<EXT3_BLOCK_SIZE_BITS(sb))
>> +((char *)de - bh->b_data))) {
>> brelse (bh);
>> *err = ERR_BAD_DX_DIR;
>> goto errout;
>> }
>> *res_dir = de;
>> dx_release (frames);
>> return bh;
>> }
>>
>> Is it possible that this loop can get stuck with a corrupt filesystem image?
>
> It certainly is. This is the same problem as the first case reported
> at http://bugzilla.kernel.org/show_bug.cgi?id=10882. There is a patch
> in -mm for it already (2fde9f7a0faabe821b31ccd982d482c21f7c503f),
> posted here: http://marc.info/?l=linux-kernel&m=121486328013470.
>
> Hopefully that should fix the problem for you.

Oh, right. Thanks!

(This patch looks much shorter than the one I found for ext2, though,
i.e. commit aa4f3f285643956bb614cf7b8f88e15f3a375886 from the
historical git repository. Does it fix all the right cases? I don't
mean to troll -- I just wanted to be sure you knew about it.)

I'll try it and report back if there's any trouble. Thanks,

Vegard

--
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
-- E. W. Dijkstra, EWD1036
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/