Commit graph

262 commits

Author SHA1 Message Date
Stephen Hemminger
b0dee79103 hv_netvsc: fix locking during VF setup
The dev_uc/mc_sync calls need to have the device address list
locked. This was spotted by running with lockdep enabled.

Fixes: bee9d41b37 ("hv_netvsc: propagate rx filters to VF")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-08 12:48:57 -05:00
Stephen Hemminger
35a57b7fef hv_netvsc: fix locking for rx_mode
The rx_mode operation handler is different than other callbacks
in that is not always called with rtnl held. Therefore use
RCU to ensure that references are valid.

Fixes: bee9d41b37 ("hv_netvsc: propagate rx filters to VF")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-08 12:48:56 -05:00
Stephen Hemminger
bee9d41b37 hv_netvsc: propagate rx filters to VF
The netvsc device should propagate filters to the SR-IOV VF
device (if present). The flags also need to be propagated to the
VF device as well. This only really matters on local Hyper-V
since Azure does not support multiple addresses.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 22:18:21 -05:00
Stephen Hemminger
b3bf5666a5 hv_netvsc: defer queue selection to VF
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 <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 22:18:20 -05:00
Stephen Hemminger
f4950e4586 hv_netvsc: only wake transmit queue if link is up
Don't wake transmit queues if link is not up yet.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 22:18:20 -05:00
Stephen Hemminger
cfd8afd986 hv_netvsc: empty current transmit aggregation if flow blocked
If the transmit queue is known full, then don't keep aggregating
data. And the cp_partial flag which indicates that the current
aggregation buffer is full can be folded in to avoid more
conditionals.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 15:57:39 -05:00
Stephen Hemminger
345ac08990 hv_netvsc: pass netvsc_device to receive callback
The netvsc_receive_callback function was using RCU to find the
appropriate underlying netvsc_device. Since calling function already
had that pointer, this was unnecessary.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 15:57:39 -05:00
Stephen Hemminger
79cf1bae38 hv_netvsc: simplify function args in receive status path
The caller (netvsc_receive) already has the net device pointer,
and should just pass that to functions rather than the hyperv device.
This eliminates several impossible error paths in the process.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 15:57:38 -05:00
Stephen Hemminger
f61a9d62b2 hv_netvsc: track memory allocation failures in ethtool stats
When skb can not be allocated, update ethtool statisitics
rather than rx_dropped which is intended for netif_receive.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 15:57:38 -05:00
Haiyang Zhang
41f61db2cd hv_netvsc: Fix the TX/RX buffer default sizes
The values were not computed correctly. There are no significant
visible impact, though.

The intended size of RX buffer is 16 MB, and the default slot size is 1728.
So, NETVSC_DEFAULT_RX should be 16*1024*1024 / 1728 = 9709.

The intended size of TX buffer is 1 MB, and the slot size is 6144.
So, NETVSC_DEFAULT_TX should be 1024*1024 / 6144 = 170.

The patch puts the formula directly into the macro, and moves them to
hyperv_net.h, together with related macros.

Fixes: 5023a6db73 ("netvsc: increase default receive buffer size")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 13:25:04 -05:00
Stephen Hemminger
f5a2255010 hv_netvsc: optimize initialization of RNDIS header
The memset of the whole maximum possible RNDIS header is unnecessary.
For the main part of the header use a structure assignment.

No need to memset the whole per packet info. Instead rely on caller to
set what it wants. Also get rid of cast to void and signed/unsigned
conversion. Now return pointer to per packet data (rather than the
header) which simplifies use by code setting up the packet data.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-03 10:10:02 -05:00
Stephen Hemminger
a7f99d0f2b hv_netvsc: use reciprocal divide to speed up percent calculation
Every packet sent checks the available ring space. The calculation
can be sped up by using reciprocal divide which is multiplication.

Since ring_size can only be configured by module parameter, so it doesn't
have to be passed around everywhere. Also it should be unsigned
since it is number of pages.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-03 10:10:02 -05:00
Vitaly Kuznetsov
aefd80e874 hv_netvsc: preserve hw_features on mtu/channels/ringparam changes
rndis_filter_device_add() is called both from netvsc_probe() when we
initially create the device and from set channels/mtu/ringparam
routines where we basically remove the device and add it back.

hw_features is reset in rndis_filter_device_add() and filled with
host data. However, we lose all additional flags which are set outside
of the driver, e.g. register_netdevice() adds NETIF_F_SOFT_FEATURES and
many others.

Unfortunately, calls to rndis_{query_hwcaps(), _set_offload_params()}
calls cannot be avoided on every RNDIS reset: host expects us to set
required features explicitly. Moreover, in theory hardware capabilities
can change and we need to reflect the change in hw_features.

Reset net->hw_features bits according to host data in
rndis_netdev_set_hwcaps(), clear corresponding feature bits
from net->features in case some features went missing (will never happen
in real life I guess but let's be consistent).

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-16 10:49:00 +09:00
Haiyang Zhang
39e91cfbf6 hv_netvsc: Rename tx_send_table to tx_table
Simplify the variable name: tx_send_table

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-14 18:42:55 -07:00
Haiyang Zhang
47371300df hv_netvsc: Rename ind_table to rx_table
Rename this variable because it is the Receive indirection
table.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-14 18:42:55 -07:00
Haiyang Zhang
0518ec4f9d hv_netvsc: Add ethtool handler to set and get TCP hash levels
The patch supports the options to switch TCP hash level between
L3 and L4 by ethtool command. TCP over IPv4 and v6 can be set
differently. The default hash level is L4. We currently only
allow switching TX hash level from within the guests.

For example, for TCP over IPv4 on eth0:
To include TCP port numbers in hashing:
	ethtool -N eth0 rx-flow-hash tcp4 sdfn
To exclude TCP port numbers in hashing:
	ethtool -N eth0 rx-flow-hash tcp4 sd
To show TCP hash level:
	ethtool -n eth0 rx-flow-hash tcp4

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-08 10:11:01 -07:00
Haiyang Zhang
486e398105 hv_netvsc: Change the hash level variable to bit flags
This simplifies the logic and make it easier to add more
options.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-08 10:11:01 -07:00
David Ahern
42ab19ee90 net: Add extack to upper device linking
Add extack arg to netdev_upper_dev_link and netdev_master_upper_dev_link

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04 21:39:33 -07:00
Simon Xiao
09af87d18f hv_netvsc: report stop_queue and wake_queue
Report the numbers of events for stop_queue and wake_queue in
ethtool stats.

Example:
ethtool -S eth0
NIC statistics:
	...
	stop_queue: 7
	wake_queue: 7
	...

Signed-off-by: Simon Xiao <sixiao@microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-01 04:10:30 +01:00
Haiyang Zhang
6450f8f269 hv_netvsc: Fix the real number of queues of non-vRSS cases
For older hosts without multi-channel (vRSS) support, and some error
cases, we still need to set the real number of queues to one.
This patch adds this missing setting.

Fixes: 8195b1396e ("hv_netvsc: fix deadlock on hotplug")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-25 20:20:51 -07:00
Alex Ng
0ab09befdb hv_netvsc: fix send buffer failure on MTU change
If MTU is changed the host would reject the send buffer change.
This problem is result of recent change to allow changing send
buffer size.

Every time we change the MTU, we store the previous net_device section
count before destroying the buffer, but we don’t store the previous
section size. When we reinitialize the buffer, its size is calculated
by multiplying the previous count and previous size. Since we
continuously increase the MTU, the host returns us a decreasing count
value while the section size is reinitialized to 1728 bytes every
time.

This eventually leads to a condition where the calculated buf_size is
so small that the host rejects it.

Fixes: 8b5327975a ("netvsc: allow controlling send/recv buffer size")
Signed-off-by: Alex Ng <alexng@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-21 15:17:16 -07:00
Stephen Hemminger
5023a6db73 netvsc: increase default receive buffer size
The default receive buffer size was reduced by recent change
to a value which was appropriate for 10G and Windows Server 2016.
But the value is too small for full performance with 40G on Azure.
Increase the default back to maximum supported by host.

Fixes: 8b5327975a ("netvsc: allow controlling send/recv buffer size")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-15 14:41:12 -07:00
Stephen Hemminger
8195b1396e hv_netvsc: fix deadlock on hotplug
When a virtual device is added dynamically (via host console), then
the vmbus sends an offer message for the primary channel. The processing
of this message for networking causes the network device to then
initialize the sub channels.

The problem is that setting up the sub channels needs to wait until
the subsequent subchannel offers have been processed. These offers
come in on the same ring buffer and work queue as where the primary
offer is being processed; leading to a deadlock.

This did not happen in older kernels, because the sub channel waiting
logic was broken (it wasn't really waiting).

The solution is to do the sub channel setup in its own work queue
context that is scheduled by the primary channel setup; and then
happens later.

Fixes: 732e49850c ("netvsc: fix race on sub channel creation")
Reported-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-11 14:21:30 -07:00
Haiyang Zhang
db3cd7af9d hv_netvsc: Fix the channel limit in netvsc_set_rxfh()
The limit of setting receive indirection table value should be
the current number of channels, not the VRSS_CHANNEL_MAX.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 20:39:12 -07:00
Haiyang Zhang
06be580ac7 hv_netvsc: Simplify the limit check in netvsc_set_channels()
Because of the following code, net->num_tx_queues equals to
VRSS_CHANNEL_MAX, and max_chn is less than or equals to VRSS_CHANNEL_MAX.

netvsc_drv.c:
alloc_etherdev_mq(sizeof(struct net_device_context),
                                VRSS_CHANNEL_MAX);
rndis_filter.c:
net_device->max_chn = min_t(u32, VRSS_CHANNEL_MAX, num_possible_rss_qs);

So this patch removes the unnecessary limit check before comparing
with "max_chn".

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 20:39:12 -07:00
Haiyang Zhang
715e2ec532 hv_netvsc: Clean up an unused parameter in rndis_filter_set_rss_param()
This patch removes the parameter, num_queue in
rndis_filter_set_rss_param(), which is no longer in use.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 20:39:12 -07:00
Stephen Hemminger
ec158f77de netvsc: allow driver to be removed even if VF is present
If VF is attached then can still allow netvsc driver module to
be removed. Just have to make sure and do the cleanup.

Also, avoid extra rtnl round trip when calling unregister.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 20:31:19 -07:00
Stephen Hemminger
9a0c48df0d netvsc: cleanup datapath switch
Use one routine for datapath up/down. Don't need to reopen
the rndis layer.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 20:31:19 -07:00
David S. Miller
6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
stephen hemminger
9b4e946ce1 netvsc: fix deadlock betwen link status and removal
There is a deadlock possible when canceling the link status
delayed work queue. The removal process is run with RTNL held,
and the link status callback is acquring RTNL.

Resolve the issue by using trylock and rescheduling.
If cancel is in process, that block it from happening.

Fixes: 122a5f6410 ("staging: hv: use delayed_work for netvsc_send_garp()")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 21:59:08 -07:00
Haiyang Zhang
c6f71c418f hv_netvsc: Fix rndis_filter_close error during netvsc_remove
We now remove rndis filter before unregister_netdev(), which calls
device close. It involves closing rndis filter already removed.

This patch fixes this error.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 21:55:59 -07:00
Haiyang Zhang
4823eb2f3a hv_netvsc: Add ethtool handler to set and get UDP hash levels
The patch add the functions to switch UDP hash level between
L3 and L4 by ethtool command. UDP over IPv4 and v6 can be set
differently. The default hash level is L4. We currently only
allow switching TX hash level from within the guests.

On Azure, fragmented UDP packets have high loss rate with L4
hashing. Using L3 hashing is recommended in this case.

For example, for UDP over IPv4 on eth0:
To include UDP port numbers in hasing:
	ethtool -N eth0 rx-flow-hash udp4 sdfn
To exclude UDP port numbers in hasing:
	ethtool -N eth0 rx-flow-hash udp4 sd
To show UDP hash level:
	ethtool -n eth0 rx-flow-hash udp4

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:08:12 -07:00
Haiyang Zhang
4c0e2cbfd9 hv_netvsc: Clean up unused parameter from netvsc_get_rss_hash_opts()
The parameter "nvdev" is not in use.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:08:11 -07:00
Haiyang Zhang
fcba1569a0 hv_netvsc: Clean up unused parameter from netvsc_get_hash()
The parameter "sk" is not in use.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:08:11 -07:00
stephen hemminger
cad5c19770 netvsc: keep track of some non-fatal overload conditions
Add ethtool statistics for case where send chimmeny buffer is
exhausted and driver has to fall back to doing scatter/gather
send. Also, add statistic for case where ring buffer is full and
receive completions are delayed.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 14:00:07 -07:00
stephen hemminger
8b5327975a netvsc: allow controlling send/recv buffer size
Control the size of the buffer areas via ethtool ring settings.
They aren't really traditional hardware rings, but host API breaks
receive and send buffer into chunks. The final size of the chunks are
controlled by the host.

The default value of send and receive buffer area for host DMA
is much larger than it needs to be. Experimentation shows that
4M receive and 1M send is sufficient.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 14:00:06 -07:00
stephen hemminger
ea5a32c00b netvsc: remove unnecessary check for NULL hdr
The function init_page_array is always called with a valid pointer
to RNDIS header. No check for NULL is needed.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:43 -07:00
stephen hemminger
00f5024e82 netvsc: remove unnecessary cast of void pointer
Assignment to a typed pointer is sufficient in C.
No cast is needed.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:43 -07:00
stephen hemminger
89bb42b113 netvsc: whitespace cleanup
Fix some minor indentation issues.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:43 -07:00
stephen hemminger
68d715f685 netvsc: check error return when restoring channels and mtu
If setting new values fails, and the attempt to restore original
settings fails. Then log an error and leave device down.
This should never happen, but if it does don't go down in flames.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:42 -07:00
stephen hemminger
16ba326600 netvsc: propagate MAC address change to VF slave
If VF is slaved to synthetic device, then any change to netvsc
MAC address should be propagated to the slave device.

If slave device doesn't support MAC address change then it
should also be an error to attempt to change synthetic NIC MAC
address.

It also fixes the error unwind in the original code.
If give a bad address, the old code would change the device
MAC address anyway.

Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:42 -07:00
stephen hemminger
6123c66854 netvsc: delay setup of VF device
When VF device is discovered, delay bring it automatically up in
order to allow userspace to some simple changes (like renaming).

Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 13:59:42 -07:00
stephen hemminger
7b83f52047 netvsc: make sure and unregister datapath
Go back to switching datapath directly in the notifier callback.
Otherwise datapath might not get switched on unregister.

No need for calling the NOTIFY_PEERS notifier since that is only for
a gratitious ARP/ND packet; but that is not required with Hyper-V
because both VF and synthetic NIC have the same MAC address.

Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Fixes: 0c195567a8 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-08 18:09:52 -07:00
stephen hemminger
fb84af8a43 netvsc: fix rtnl deadlock on unregister of vf
With new transparent VF support, it is possible to get a deadlock
when some of the deferred work is running and the unregister_vf
is trying to cancel the work element. The solution is to use
trylock and reschedule (similar to bonding and team device).

Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Fixes: 0c195567a8 ("netvsc: transparent VF management")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-06 21:28:10 -07:00
stephen hemminger
0c195567a8 netvsc: transparent VF management
This patch implements transparent fail over from synthetic NIC to
SR-IOV virtual function NIC in Hyper-V environment. It is a better
alternative to using bonding as is done now. Instead, the receive and
transmit fail over is done internally inside the driver.

Using bonding driver has lots of issues because it depends on the
script being run early enough in the boot process and with sufficient
information to make the association. This patch moves all that
functionality into the kernel.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-02 16:55:33 -07:00
David S. Miller
29fda25a2d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two minor conflicts in virtio_net driver (bug fix overlapping addition
of a helper) and MAINTAINERS (new driver edit overlapping revamp of
PHY entry).

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-01 10:07:50 -07:00
stephen hemminger
02b6de01af netvsc: remove unnecessary indirection of page_buffer
The internal API was passing struct hv_page_buffer **
when only simple struct hv_page_buffer * was necessary
for passing an array.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-29 15:25:43 -07:00
stephen hemminger
867047c451 netvsc: fix warnings reported by lockdep
This includes a bunch of fixups for issues reported by
lockdep.
   * ethtool routines can assume RTNL
   * send is done with RCU lock (and BH disable)
   * avoid refetching internal device struct (netvsc)
     instead pass it as a parameter.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-29 15:25:43 -07:00
stephen hemminger
d6aac1f218 netvsc: fix return value for set_channels
The error and normal case got swapped.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-29 15:25:43 -07:00
stephen hemminger
80d887dbb6 Revert "netvsc: optimize calculation of number of slots"
The logic for computing page buffer scatter does not take into
account the impact of compound pages. Therefore the optimization
to compute number of slots was incorrect and could cause stack
corruption a skb was sent with lots of fragments from huge pages.

This reverts commit 60b86665af.

Fixes: 60b86665af ("netvsc: optimize calculation of number of slots")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-25 21:26:08 -07:00