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From: Jarek Poplawski <jarkao2@o2.pl>
To: Dale Farnsworth <dale@farnsworth.org>
Cc: Thibaut VARENE <T-Bone@parisc-linux.org>,
	netdev@vger.kernel.org, mlachwani@mvista.com
Subject: Re: [PATCH] Re: kernel BUG in eth_alloc_tx_desc_index at drivers/net/mv643xx_eth.c:1069!
Date: Tue, 23 Jan 2007 09:17:09 +0100	[thread overview]
Message-ID: <20070123081709.GA1925@ff.dom.local> (raw)
In-Reply-To: <20070122170615.GA15293@xyzzy.farnsworth.org>

On Mon, Jan 22, 2007 at 10:06:16AM -0700, Dale Farnsworth wrote:
> Jarek and Thibaut,
> 
> Thank you both very much for your work finding and fixing this bug.
> Jarek, can you verify that the following patch fixes the problem you
> were seeing?
> 
> -Dale

Sorry, only Thibaut can verify this. I don't have
such card.

I can only confirm that your patch fixes unproper
locking of mp->tx_desc_count in the while condition.
But I'm not sure your way is optimal now because
mp->tx_desc_count is checked 2 times per every loop.
I think it is right only if you know the function
mv643xx_eth_free_tx_descs is called mostly while 
mp->tx_desc_count == 0 or 1.

> ----- Patch follows -----
> 
> From: Dale Farnsworth <dale@farnsworth.org>
> 
> mv643xx_eth: Fix race condition in mv643xx_eth_free_tx_descs
> 
> The bug was found and isolated by Thibaut VARENE <T-Bone@parisc-linux.org>
> and Jarek Poplawski <jarkao2@o2.pl>.  This patch is a modification of their
> fixes.  We acquire and release the lock for each descriptor that is freed
> to minimize the time the lock is held.
> 
> ---

From: Dale Farnsworth <dale@farnsworth.org>
 
mv643xx_eth: Fix race condition in mv643xx_eth_free_tx_descs
 
The bug was found and isolated by Thibaut VARENE <T-Bone@parisc-linux.org>
and Jarek Poplawski <jarkao2@o2.pl> noticed a locking problem.  This patch
is a modification of their fixes.  We acquire and release the lock for each
descriptor that is freed to minimize the time the lock is held.
 
---

I did small adjustment of my role here.

Regards,
Jarek P.

  reply	other threads:[~2007-01-23  8:14 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-01-05 19:03 kernel BUG in eth_alloc_tx_desc_index at drivers/net/mv643xx_eth.c:1069! Thibaut VARENE
2007-01-09  9:26 ` Jarek Poplawski
2007-01-09 10:27   ` Thibaut VARENE
2007-01-09 10:52     ` Jarek Poplawski
2007-01-09 10:56       ` Thibaut VARENE
2007-01-09 11:48         ` Jarek Poplawski
2007-01-09 10:57     ` Jarek Poplawski
2007-01-09 13:02     ` Jarek Poplawski
2007-01-09 17:44       ` Thibaut VARENE
2007-01-09 20:05         ` Dale Farnsworth
2007-01-09 21:05           ` Thibaut VARENE
2007-01-10 17:12             ` Thibaut VARENE
2007-01-11 10:42               ` [PATCH] " Jarek Poplawski
2007-01-21 12:18                 ` Thibaut VARENE
2007-01-21 13:02                   ` Thibaut VARENE
2007-01-22 10:02                     ` Jarek Poplawski
2007-01-22 17:06                       ` Dale Farnsworth
2007-01-23  8:17                         ` Jarek Poplawski [this message]
2007-01-23 11:52                         ` Thibaut VARENE
2007-01-23 12:42                           ` Thibaut VARENE

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