From 35fbbccfb417385c1c8cc6f799154ea1ebdc22ef Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Wed, 19 Jul 2017 11:53:18 -0700 Subject: [PATCH] netvsc: save pointer to parent netvsc_device in channel table Keep back pointer in the per-channel data structure to avoid any possible RCU related issues when napi poll is called but netvsc_device is in RCU limbo. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/hyperv/hyperv_net.h | 1 + drivers/net/hyperv/netvsc.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h index 0054b6929f6e..d13572879e7e 100644 --- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -727,6 +727,7 @@ struct net_device_context { /* Per channel data */ struct netvsc_channel { struct vmbus_channel *channel; + struct netvsc_device *net_device; const struct vmpacket_descriptor *desc; struct napi_struct napi; struct multi_send_data msd; diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c index 3c6f3ae520d9..c15640c6fd83 100644 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -1224,11 +1224,11 @@ int netvsc_poll(struct napi_struct *napi, int budget) { struct netvsc_channel *nvchan = container_of(napi, struct netvsc_channel, napi); + struct netvsc_device *net_device = nvchan->net_device; struct vmbus_channel *channel = nvchan->channel; struct hv_device *device = netvsc_channel_to_device(channel); u16 q_idx = channel->offermsg.offer.sub_channel_index; struct net_device *ndev = hv_get_drvdata(device); - struct netvsc_device *net_device = net_device_to_netvsc_device(ndev); int work_done = 0; /* If starting a new interval */ @@ -1307,6 +1307,7 @@ struct netvsc_device *netvsc_device_add(struct hv_device *device, struct netvsc_channel *nvchan = &net_device->chan_table[i]; nvchan->channel = device->channel; + nvchan->net_device = net_device; } /* Enable NAPI handler before init callbacks */