[Jaunty SRU] LP#345710 [v2: description modified] iwl3945: cancel rfkill_poll with sync when?the module is exiting

[Huaxu Wan]

On 11:31 Wed 01 Jul, Stefan Bader wrote:
> Huaxu Wan wrote:
>> Hi Stefan,
>>
>> The patch is fine for me. It works for 2.6.28 kernel. But, this bug is
>> not found with 2.6.30 or above kernel. This patch is not valuable to
>> 2.6.30+, but 2.6.28 stable. I have no idea about whether it should be
>> send to upstream. Please do it if you want.
>>
>
> Hi Huaxu,
>
> how stupid of me. I guess we can forget about moving he cancel statement. 
> I still have to get it verified but looking at the upstream code we got 
> the following patch which moves ieee80211_unregister_hw from below 
> stopping the rfkill_poll to above. And (though I did not follow the code 
> completely) it seems likely that ieee80211_unregister_hw could call 
> iwl3945_mac_stop which restarts the delayed work.
> That patch went in after 2.6.29-rc2 and the one doing the cancel as sync 
> after 2.6.30-rc1. So the final fix is/was with 2.6.30.
> Does this sound reasonable?

Hi Stefan,

I'm confused :S. 

Let me clarify something. The original bug(system freezed when module exit)
was introduced by backport the patch [iwl3945: report killswitch changes
even if the interface is down(2663516d8fb896430bf42dce41b3e2f141d63bd5)]
to fix a bug about rfkill. Then the patch we are discussing fix the bug.

I once tried to reproduce the system freeze bug with 2.6.30 without the
patch, but seems it was fixed in another way.

Upstream wanted to pick the patch into 2.6.30 because it's reasonable to
cancel rfkill_poll with cancel_delayed_work_sync, I think. However, I 
happened to be on vacation when the upstream guy ask for patch. Since no
response from me, they made a patch directly. But, the patch does not
fix the bug in 2.6.28.  ^_^

>
> Regards,
> Stefan
>
> -- 
>
> When all other means of communication fail, try words!
>
>

> >From d552bfb65241a35d48e44ddb0d27e0454f579ab4 Mon Sep 17 00:00:00 2001
> From: Kolekar, Abhijeet <abhijeet.kolekar at intel.com>
> Date: Fri, 19 Dec 2008 10:37:41 +0800
> Subject: [PATCH] iwl3945: release resources before shutting down
> 
> Release resource before shutting down and notify upper stack.
> 
> Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar at intel.com>
> Signed-off-by: Zhu Yi <yi.zhu at intel.com>
> Signed-off-by: John W. Linville <linville at tuxdriver.com>
> Signed-off-by: Stefan Bader <stefan.bader at canonical.com>
> ---
>  drivers/net/wireless/iwlwifi/iwl3945-base.c |   10 ++++++----
>  1 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
> index b845097..17f01a6 100644
> --- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
> +++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
> @@ -7722,7 +7722,12 @@ static void __devexit iwl3945_pci_remove(struct pci_dev *pdev)
>  
>  	set_bit(STATUS_EXIT_PENDING, &priv->status);
>  
> -	iwl3945_down(priv);
> +	if (priv->mac80211_registered) {
> +		ieee80211_unregister_hw(priv->hw);
> +		priv->mac80211_registered = 0;
> +	} else {
> +		iwl3945_down(priv);
> +	}
>  
>  	/* make sure we flush any pending irq or
>  	 * tasklet for the driver
> @@ -7745,9 +7750,6 @@ static void __devexit iwl3945_pci_remove(struct pci_dev *pdev)
>  	iwl3945_unset_hw_params(priv);
>  	iwl3945_clear_stations_table(priv);
>  
> -	if (priv->mac80211_registered)
> -		ieee80211_unregister_hw(priv->hw);
> -
>  	/*netif_stop_queue(dev); */
>  	flush_workqueue(priv->workqueue);
>  
> -- 
> 1.5.4.3
> 


-- 
Thanks
Huaxu