linux-stable.git/drivers/net/hyperv, branch v4.14.44

hv_netvsc: Fix net device attach on older Windows hosts

2018-05-25T14:17:30+00:00

[ Commit 55be9f25be1ca5bda75c39808fc77e42691bc07f upstream. ]

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 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Ensure correct teardown message sequence order

2018-05-25T14:17:30+00:00

[ Commit a56d99d714665591fed8527b90eef21530ea61e0 upstream. ]

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 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Split netvsc_revoke_buf() and netvsc_teardown_gpadl()

2018-05-25T14:17:30+00:00

[ Commit 7992894c305eaf504d005529637ff8283d0a849d upstream. ]

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 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: Use Windows version instead of NVSP version on GPAD teardown

2018-05-25T14:17:30+00:00

commit 2afc5d61a7197de25a61f54ea4ecfb4cb62b1d42A upstram

When changing network interface settings, Windows guests
older than WS2016 can no longer shutdown. This was addressed
by commit 0ef58b0a05c12 ("hv_netvsc: change GPAD teardown order
on older versions"), however the issue also occurs on WS2012
guests that share NVSP protocol versions with WS2016 guests.
Hence we use Windows version directly to differentiate them.

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

hv_netvsc: common detach logic

2018-05-25T14:17:29+00:00

[ Commit 7b2ee50c0cd513a176a26a71f2989facdd75bfea upstream. ]

Make common function for detaching internals of device
during changes to MTU and RSS. Make sure no more packets
are transmitted and all packets have been received before
doing device teardown.

Change the wait logic to be common and use usleep_range().

Changes transmit enabling logic so that transmit queues are disabled
during the period when lower device is being changed. And enabled
only after sub channels are setup. This avoids issue where it could
be that a packet was being sent while subchannel was not initialized.

Fixes: 8195b1396ec8 ("hv_netvsc: fix deadlock on hotplug")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: change GPAD teardown order on older versions

2018-05-25T14:17:29+00:00

[ Commit 0ef58b0a05c127762f975c3dfe8b922e4aa87a29 upstream. ]

On older versions of Windows, the host ignores messages after
vmbus channel is closed.

Workaround this by doing what Windows does and send the teardown
before close on older versions of NVSP protocol.

Reported-by: Mohammed Gamal 
Fixes: 0cf737808ae7 ("hv_netvsc: netvsc_teardown_gpadl() split")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: use RCU to fix concurrent rx and queue changes

2018-05-25T14:17:29+00:00

[ Commit 02400fcee2542ee334a2394e0d9f6efd969fe782 upstream. ]

The receive processing may continue to happen while the
internal network device state is in RCU grace period.
The internal RNDIS structure is associated with the
internal netvsc_device structure; both have the same
RCU lifetime.

Defer freeing all associated parts until after grace
period.

Fixes: 0cf737808ae7 ("hv_netvsc: netvsc_teardown_gpadl() split")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: disable NAPI before channel close

2018-05-25T14:17:29+00:00

[ Commit 8348e0460ab1473f06c8b824699dd2eed3c1979d upstream. ]

This makes sure that no CPU is still process packets when
the channel is closed.

Fixes: 76bb5db5c749 ("netvsc: fix use after free on module removal")
Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: defer queue selection to VF

2018-05-25T14:17:28+00:00

[ Commit b3bf5666a51068ad5ddd89a76ed877101ef3bc16 upstream. ]

When VF is used for accelerated networking it will likely have
more queues (and different policy) than the synthetic NIC.
This patch defers the queue policy to the VF so that all the
queues can be used. This impacts workloads like local generate UDP.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

hv_netvsc: fix race in napi poll when rescheduling

2018-05-25T14:17:28+00:00

[ Commit d64e38ae690e3337db0d38d9b149a193a1646c4b upstream. ]

There is a race between napi_reschedule and re-enabling interrupts
which could lead to missed host interrrupts.  This occurs when
interrupts are re-enabled (hv_end_read) and vmbus irq callback
(netvsc_channel_cb) has already scheduled NAPI.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman