Re: [Madwifi-devel] Probable sk_buffer memory leak in BSD branch

[Bruno R. <bru...@4g...>]

hey olivier!

thanks for noting this! i've added the missing dev_free_skb() to the madwif=
i=20
bsd branch. i'm looking forwared to your power save queue bug reports ;)

ethan, could you give us a note if this fixed your problems too, please?

bruno


On Thursday 30 June 2005 15:15, Olivier Tchilinguirian wrote:
> Hi,
> I'm testing the MadWifi driver on RH linux 2.4.20-18.7 with D-Link DWL-G5=
20
> card, and I noticed a memory problem which freeze my server after ~24h of
> uptime.
>
> When server crash, the we could see this kind of msg on console "ath0: no
> skbuff (ath_rx_tasklet) (Fatal Error)".
>
> So I started to debug driver and analyze /proc/slabinfo.
>
> I noticed a hudge number of "skbuff_head_cache" and "size-4096" memory
> pages.
>
> Step by step I traced into the rx/tx functions and noticed that the
> unreleased buffers problem occurred when "power save mode" is on.
>
> obviously the problem occurs after calling "ieee80211_decap" sub in
> ieee80211_input() function.
> The ieee80211_decap() func returns a NULL skb pointer without freeing data
> before.
>
> Here is the code which returns a null value for skb on the ieee80211_decap
> func...
> I added a dev_kfree_skb() before returning NULL pointer to fix the
> problem...
>
> if (skb->len < hdrlen + sizeof(*llc)) {
>      printk("ieee80211_decap: skb len (%d) < hdrlen (%d) + llc (%d) skbad=
dr
> %lx \n",sizeof(*llc),skb->len,hdrlen,(long unsigned int)skb);
>
>      // It's a customized overloaded dev_kfree_skb func. used for debug
>      // Replace it with dev_kfree_skb(skb) for updating driver source code
>      my_dev_kfree_skb(skb,__func__);
>      /* XXX stat, msg */
>      return NULL;
> }
>
> Furthermore I suspect the node save queue system for power save management
> to be buggy ;-)
>
> I hope this will help...
>
> Best regards,
>
> Olivier.
>
>
>
> -------------------------------------------------------
> SF.Net email is sponsored by: Discover Easy Linux Migration Strategies
> from IBM. Find simple to follow Roadmaps, straightforward articles,
> informative Webcasts and more! Get everything you need to get up to
> speed, fast. http://ads.osdn.com/?ad_id=3D7477&alloc_id=3D16492&op=3Dclick
> _______________________________________________
> Madwifi-devel mailing list
> Mad...@li...
> https://lists.sourceforge.net/lists/listinfo/madwifi-devel