From 5362855aba7159aab8f7c6573eb675d9da317914 Mon Sep 17 00:00:00 2001 From: Vitaly Kuznetsov Date: Thu, 9 Jun 2016 12:44:03 +0200 Subject: 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 Acked-by: Haiyang Zhang Signed-off-by: David S. Miller --- drivers/net/hyperv/netvsc.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-) (limited to 'drivers/net/hyperv/netvsc.c') diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 96f00c0261fa..6909c322de4e 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -244,7 +244,6 @@ static int netvsc_destroy_buf(struct hv_device *device) static int netvsc_init_buf(struct hv_device *device) { int ret = 0; - unsigned long t; struct netvsc_device *net_device; struct nvsp_message *init_packet; struct net_device *ndev; @@ -305,9 +304,7 @@ static int netvsc_init_buf(struct hv_device *device) goto cleanup; } - t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ); - BUG_ON(t == 0); - + wait_for_completion(&net_device->channel_init_wait); /* Check the response */ if (init_packet->msg.v1_msg. @@ -390,8 +387,7 @@ static int netvsc_init_buf(struct hv_device *device) goto cleanup; } - t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ); - BUG_ON(t == 0); + wait_for_completion(&net_device->channel_init_wait); /* Check the response */ if (init_packet->msg.v1_msg. @@ -445,7 +441,6 @@ static int negotiate_nvsp_ver(struct hv_device *device, { struct net_device *ndev = hv_get_drvdata(device); int ret; - unsigned long t; memset(init_packet, 0, sizeof(struct nvsp_message)); init_packet->hdr.msg_type = NVSP_MSG_TYPE_INIT; @@ -462,10 +457,7 @@ static int negotiate_nvsp_ver(struct hv_device *device, if (ret != 0) return ret; - t = wait_for_completion_timeout(&net_device->channel_init_wait, 5*HZ); - - if (t == 0) - return -ETIMEDOUT; + wait_for_completion(&net_device->channel_init_wait); if (init_packet->msg.init_msg.init_complete.status != NVSP_STAT_SUCCESS) -- cgit v1.2.3