On 2019-11-20 12:59, Markus Theil wrote:
> On 11/20/19 12:46 PM, Felix Fietkau wrote:
>> Fixes potential RCU issues and avoids calling ieee80211_rx_napi with softirq
>> enabled.
>>
>> Reported-by: Markus Theil <markus.theil@xxxxxxxxxxxxx>
>> Signed-off-by: Felix Fietkau <nbd@xxxxxxxx>
>> ---
>> drivers/net/wireless/mediatek/mt76/dma.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
>> index 6173c80189ba..ed0ee2d4a452 100644
>> --- a/drivers/net/wireless/mediatek/mt76/dma.c
>> +++ b/drivers/net/wireless/mediatek/mt76/dma.c
>> @@ -528,7 +528,7 @@ mt76_dma_rx_poll(struct napi_struct *napi, int budget)
>> dev = container_of(napi->dev, struct mt76_dev, napi_dev);
>> qid = napi - dev->napi;
>>
>> - rcu_read_lock();
>> + rcu_read_lock_bh();
>>
>> do {
>> cur = mt76_dma_rx_process(dev, &dev->q_rx[qid], budget - done);
>> @@ -536,7 +536,7 @@ mt76_dma_rx_poll(struct napi_struct *napi, int budget)
>> done += cur;
>> } while (cur && done < budget);
>>
>> - rcu_read_unlock();
>> + rcu_read_unlock_bh();
>>
>> if (done < budget && napi_complete(napi))
>> dev->drv->rx_poll_complete(dev, qid);
>
> This patch is incomplete. The same problem exists for usb. I'll send a fix for that.
How so? On usb, it is called from a tasklet already.
- Felix
