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Date: Wed, 29 Jan 2014 07:04:25 -0300
From: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
To: Fabian Frederick <fabf@skynet.be>,
 Brian Norris <computersforpeace@gmail.com>
Subject: Re: [PATCH 3/4] mtd: block2mtd: check device size
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Hi Fabian,

I saw you sent a v2 for one of the patches on this series,
but maybe this is worth considering too.

On Thu, Jan 23, 2014 at 08:53:31PM +0100, Fabian Frederick wrote:
[..]
> -/* FIXME: ensure that mtd->size % erase_size == 0 */
>  static struct block2mtd_dev *add_device(char *devname, int erase_size)
>  {
>  	const fmode_t mode = FMODE_READ | FMODE_WRITE | FMODE_EXCL;
> @@ -250,6 +249,11 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size)
>  		goto devinit_err1;
>  	}
>  
> +	if ((long)dev->blkdev->bd_inode->i_size % erase_size) {
> +		pr_err("erasesize muse be a divisor of device size\n");
> +		goto devinit_err1;
> +	}
> +

Brian: What do you think?

Fabian: Have you tested this patch? Can you elaborate a bit more about
the effect it would have, compared to the current behavior?
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com