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Subject: Re: question about drivers/mtd/ubi/cdev.c
From: Artem Bityutskiy <dedekind1@gmail.com>
To: Julia Lawall <julia@diku.dk>
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Date: Wed, 04 Aug 2010 06:06:52 +0300
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On Tue, 2010-08-03 at 22:12 +0200, Julia Lawall wrote:
> I was wondering about the following code in the function rename_volumes in 
> the file drivers/mtd/ubi/cdev.c:
> 
> list_for_each_entry(re, &rename_list, list) {
> 	...
>         if (no_remove_needed)
>                 continue;
> 	...
>         re = kzalloc(sizeof(struct ubi_rename_entry), GFP_KERNEL);
> 	if (!re) { ... }
>         re->remove = 1;
>         re->desc = desc;
>         list_add(&re->list, &rename_list);
> 	...
> }
> 
> Is there a danger of repeating computation since re is redefined and moved 
> back to the beginning of the list?

Hmm, the code is bogus, I do not know how it works, but it does, because
I tested it :-)

We should not use 're' as a temporary variable inside the loop. I guess
we can use 're1' instead. I'll change this later, when have time, unless
you submit a fix earlier :-)

Thanks for pointing this!

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)