Message-ID: <1343691085.1384.52.camel@dcbw.foobar.com> (sfid-20120731_013039_792475_A037A2E4)
Subject: Re: [PATCH] libertas: don't reset card on error when it is being
 removed
From: Dan Williams <dcbw@redhat.com>
To: Daniel Drake <dsd@laptop.org>
Cc: linville@tuxdriver.com, linux-wireless@vger.kernel.org,
	libertas-dev@lists.infradead.org
Date: Mon, 30 Jul 2012 18:31:25 -0500
In-Reply-To: <20120730215804.4BFA89D401E@zog.reactivated.net>
References: <20120730215804.4BFA89D401E@zog.reactivated.net>
Content-Type: text/plain; charset="UTF-8"
Mime-Version: 1.0
Sender: linux-wireless-owner@vger.kernel.org

On Mon, 2012-07-30 at 22:58 +0100, Daniel Drake wrote:
> On an OLPC XO-1.5 we have seen the following situation:
>  - the system starts going into suspend
>  - no wake params are set, so the mmc layer removes the card
>  - during remove, we send a command to the card
>  - that command fails, causing if_sdio's reset method to try and remove
>    the mmc card in attempt to reset it
>  - the mmc layer is not happy about being asked to remove a card that
>    it is already removing, and the kernel crashes
> 
> While the MMC layer could possibly be taught to behave better here,
> it also seems sensible for libertas not to try and reset a card if
> we're in the process of removing it anyway.
> 
> Signed-off-by: Daniel Drake <dsd@laptop.org>

Acked-by: Dan Williams <dcbw@redhat.com>

> ---
>  drivers/net/wireless/libertas/main.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/libertas/main.c b/drivers/net/wireless/libertas/main.c
> index e96ee0a..8d17cac 100644
> --- a/drivers/net/wireless/libertas/main.c
> +++ b/drivers/net/wireless/libertas/main.c
> @@ -565,7 +565,10 @@ static int lbs_thread(void *data)
>  			netdev_info(dev, "Timeout submitting command 0x%04x\n",
>  				    le16_to_cpu(cmdnode->cmdbuf->command));
>  			lbs_complete_command(priv, cmdnode, -ETIMEDOUT);
> -			if (priv->reset_card)
> +
> +			/* Reset card, but only when it isn't in the process
> +			 * of being shutdown anyway. */
> +			if (!dev->dismantle && priv->reset_card)
>  				priv->reset_card(priv);
>  		}
>  		priv->cmd_timed_out = 0;