On Tue, Sep 17, 2013 at 2:28 PM, Grumbach, Emmanuel
<emmanuel.grumbach@xxxxxxxxx> wrote:
>> On Tue, Sep 17, 2013 at 8:48 AM, Emmanuel Grumbach
>> <emmanuel.grumbach@xxxxxxxxx> wrote:
>> > __ieee80211_scan_completed is called from a worker. This means that
>> > the following flow is possible.
>> >
>> > * driver calls ieee80211_scan_completed
>> > * mac80211 cancels the scan (that is already complete)
>> > * __ieee80211_scan_complete runs
>> >
>> > When scan_work will finally run, it will see that the scan hasn't been
>> > aborted and might even trigger another scan on another band. This
>> > leads to a situation where cfg80211's scan is not done and no further
>> > scan can be issued.
>> >
>> > Fix this by setting a new flag when a HW scan is being cancelled so
>> > that no other scan will be triggered.
>> >
>> > Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@xxxxxxxxx>
>> > ---
>> [...]
>>
>> > if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
>> > - if (local->ops->cancel_hw_scan)
>> > + /*
>> > + * Make sure that __ieee80211_scan_completed doesn't trigger a
>> > + * scan on another band.
>> > + */
>> > + set_bit(SCAN_HW_CANCELLED, &local->scanning);
>> > + if (local->ops->cancel_hw_scan) {
>> > drv_cancel_hw_scan(local,
>> > rcu_dereference_protected(local->scan_sdata,
>> >
>> > lockdep_is_held(&local->mtx)));
>> > + }
>> > goto out;
>> > }
>>
>> you don't seem to clear this flag anywhere...
>>
>
> Yeah - just like SCAN_HW_SCANNING isn't cleared anywhere... but... in __ieee80211_scan_completed:
>
> local->scanning = 0;
> local->scan_chandef.chan = NULL;
>
> yes I know. Don't ask.
oh, right, i overlooked it :)
Eliad.
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