linux-stable.git/drivers/net/hyperv, branch linux-4.17.y

hv/netvsc: fix handling of fallback to single queue mode

2018-08-24T11:07:10+00:00

[ Upstream commit 916c5e1413be058d1c1f6e502db350df890730ce ]

The netvsc device may need to fallback to running in single queue
mode if host side only wants to support single queue.

Recent change for handling mtu broke this in setup logic.

Reported-by: Dan Carpenter 
Fixes: 3ffe64f1a641 ("hv_netvsc: split sub-channel setup into async and sync")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: fix network namespace issues with VF support

2018-08-03T05:47:33+00:00

[ Upstream commit 7bf7bb37f16a80465ee3bd7c6c966f96f5a075a6 ]

When finding the parent netvsc device, the search needs to be across
all netvsc device instances (independent of network namespace).

Find parent device of VF using upper_dev_get routine which
searches only adjacent list.

Fixes: e8ff40d4bff1 ("hv_netvsc: improve VF device matching")
Signed-off-by: Stephen Hemminger 

netns aware byref
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Fix napi reschedule while receive completion is busy

2018-07-25T09:26:12+00:00

[ Upstream commit 6b81b193b83e87da1ea13217d684b54fccf8ee8a ]

If out ring is full temporarily and receive completion cannot go out,
we may still need to reschedule napi if certain conditions are met.
Otherwise the napi poll might be stopped forever, and cause network
disconnect.

Fixes: 7426b1a51803 ("netvsc: optimize receive completions")
Signed-off-by: Stephen Hemminger 
Signed-off-by: Haiyang Zhang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: split sub-channel setup into async and sync

2018-07-22T13:15:59+00:00

[ Upstream commit 3ffe64f1a641b80a82d9ef4efa7a05ce69049871 ]

When doing device hotplug the sub channel must be async to avoid
deadlock issues because device is discovered in softirq context.

When doing changes to MTU and number of channels, the setup
must be synchronous to avoid races such as when MTU and device
settings are done in a single ip command.

Reported-by: Thomas Walker 
Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug")
Fixes: 732e49850c5e ("netvsc: fix race on sub channel creation")
Signed-off-by: Stephen Hemminger 
Signed-off-by: Haiyang Zhang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Fix a network regression after ifdown/ifup

2018-06-25T23:51:20+00:00

[ Upstream commit 52acf73b6e9a6962045feb2ba5a8921da2201915 ]

Recently people reported the NIC stops working after
"ifdown eth0; ifup eth0". It turns out in this case the TX queues are not
enabled, after the refactoring of the common detach logic: when the NIC
has sub-channels, usually we enable all the TX queues after all
sub-channels are set up: see rndis_set_subchannel() ->
netif_device_attach(), but in the case of "ifdown eth0; ifup eth0" where
the number of channels doesn't change, we also must make sure the TX queues
are enabled. The patch fixes the regression.

Fixes: 7b2ee50c0cd5 ("hv_netvsc: common detach logic")
Signed-off-by: Dexuan Cui 
Cc: Stephen Hemminger 
Cc: K. Y. Srinivasan 
Cc: Haiyang Zhang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: set master device

2018-05-10T21:36:20+00:00

The hyper-v transparent bonding should have used master_dev_link.
The netvsc device should look like a master bond device not
like the upper side of a tunnel.

This makes the semantics the same so that userspace applications
looking at network devices see the correct master relationshipship.

Fixes: 0c195567a8f6 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller

hv_netvsc: Fix net device attach on older Windows hosts

2018-05-10T19:37:00+00:00

On older windows hosts the net_device instance is returned to
the caller of rndis_filter_device_add() without having the presence
bit set first. This would cause any subsequent calls to network device
operations (e.g. MTU change, channel change) to fail after the device
is detached once, returning -ENODEV.

Instead of returning the device instabce, we take the exit path where
we call netif_device_attach()

Fixes: 7b2ee50c0cd5 ("hv_netvsc: common detach logic")
Signed-off-by: Mohammed Gamal 
Reviewed-by: Stephen Hemminger 
Signed-off-by: David S. Miller

hv_netvsc: Pass net_device parameter to revoke and teardown functions

2018-04-06T02:21:00+00:00

The callers to netvsc_revoke_*_buf() and netvsc_teardown_*_gpadl()
already have their net_device instances. Pass them as a paramaeter to
the function instead of obtaining them from netvsc_device struct
everytime

Signed-off-by: Mohammed Gamal 
Signed-off-by: David S. Miller

hv_netvsc: Ensure correct teardown message sequence order

2018-04-06T02:21:00+00:00

Prior to commit 0cf737808ae7 ("hv_netvsc: netvsc_teardown_gpadl() split")
the call sequence in netvsc_device_remove() was as follows (as
implemented in netvsc_destroy_buf()):
1- Send NVSP_MSG1_TYPE_REVOKE_RECV_BUF message
2- Teardown receive buffer GPADL
3- Send NVSP_MSG1_TYPE_REVOKE_SEND_BUF message
4- Teardown send buffer GPADL
5- Close vmbus

This didn't work for WS2016 hosts. Commit 0cf737808ae7
("hv_netvsc: netvsc_teardown_gpadl() split") rearranged the
teardown sequence as follows:
1- Send NVSP_MSG1_TYPE_REVOKE_RECV_BUF message
2- Send NVSP_MSG1_TYPE_REVOKE_SEND_BUF message
3- Close vmbus
4- Teardown receive buffer GPADL
5- Teardown send buffer GPADL

That worked well for WS2016 hosts, but it prevented guests on older hosts from
shutting down after changing network settings. Commit 0ef58b0a05c1
("hv_netvsc: change GPAD teardown order on older versions") ensured the
following message sequence for older hosts
1- Send NVSP_MSG1_TYPE_REVOKE_RECV_BUF message
2- Send NVSP_MSG1_TYPE_REVOKE_SEND_BUF message
3- Teardown receive buffer GPADL
4- Teardown send buffer GPADL
5- Close vmbus

However, with this sequence calling `ip link set eth0 mtu 1000` hangs and the
process becomes uninterruptible. On futher analysis it turns out that on tearing
down the receive buffer GPADL the kernel is waiting indefinitely
in vmbus_teardown_gpadl() for a completion to be signaled.

Here is a snippet of where this occurs:
int vmbus_teardown_gpadl(struct vmbus_channel *channel, u32 gpadl_handle)
{
        struct vmbus_channel_gpadl_teardown *msg;
        struct vmbus_channel_msginfo *info;
        unsigned long flags;
        int ret;

        info = kmalloc(sizeof(*info) +
                       sizeof(struct vmbus_channel_gpadl_teardown), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        init_completion(&info->waitevent);
        info->waiting_channel = channel;
[....]
        ret = vmbus_post_msg(msg, sizeof(struct vmbus_channel_gpadl_teardown),
                             true);

        if (ret)
                goto post_msg_err;

        wait_for_completion(&info->waitevent);
[....]
}

The completion is signaled from vmbus_ongpadl_torndown(), which gets called when
the corresponding message is received from the host, which apparently never happens
in that case.
This patch works around the issue by restoring the first mentioned message sequence
for older hosts

Fixes: 0ef58b0a05c1 ("hv_netvsc: change GPAD teardown order on older versions")
Signed-off-by: Mohammed Gamal 
Signed-off-by: David S. Miller

hv_netvsc: Split netvsc_revoke_buf() and netvsc_teardown_gpadl()

2018-04-06T02:21:00+00:00

Split each of the functions into two for each of send/recv buffers.
This will be needed in order to implement a fine-grained messaging
sequence to the host so that we accommodate the requirements of
different Windows versions

Fixes: 0ef58b0a05c12 ("hv_netvsc: change GPAD teardown order on older versions")
Signed-off-by: Mohammed Gamal 
Signed-off-by: David S. Miller