netvsc: get rid of completion timeouts
I'm hitting 5 second timeout in rndis_filter_set_rss_param() while setting RSS parameters for the device. When this happens we end up returning -ETIMEDOUT from the function and rndis_filter_device_add() falls back to setting net_device->max_chn = 1; net_device->num_chn = 1; net_device->num_sc_offered = 0; but after a moment the rndis request succeeds and subchannels start to appear. netvsc_sc_open() does unconditional nvscdev->num_sc_offered-- and it becomes U32_MAX-1. Consequent rndis_filter_device_remove() will hang while waiting for all U32_MAX-1 subchannels to appear and this is not going to happen. The immediate issue could be solved by adding num_sc_offered > 0 check to netvsc_sc_open() but we're getting out of sync with the host and it's not easy to adjust things later, e.g. in this particular case we'll be creating queues without a user request for it and races are expected. Same applies to other parts of the driver which have the same completion timeout. Following the trend in drivers/hv/* code I suggest we remove all these timeouts completely. As a guest we can always trust the host we're running on and if the host screws things up there is no easy way to recover anyway. Signed-off-by:Vitaly Kuznetsov <vkuznets@redhat.com> Acked-by:
Haiyang Zhang <haiyangz@microsoft.com> Signed-off-by:
David S. Miller <davem@davemloft.net>
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