The receive callback (in tasklet context) is using RCU to get reference
to associated VF network device but this is not safe. RCU read lock
needs to be held. Found by running with full lockdep debugging
enabled.
Fixes: f207c10d98 ("hv_netvsc: use RCU to protect vf_netdev")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hyper-V (and Azure) support using NVGRE which requires some extra space
for encapsulation headers. Because of this the largest allowed TSO
packet is reduced.
For older releases, hard code a fixed reduced value. For next release,
there is a better solution which uses result of host offload
negotiation.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we change MTU or the number of channels on a netvsc device we get the
following logged:
hv_netvsc bf5edba8...: net device safe to remove
hv_netvsc: hv_netvsc channel opened successfully
hv_netvsc bf5edba8...: Send section size: 6144, Section count:2560
hv_netvsc bf5edba8...: Device MAC 00:15:5d:1e:91:12 link state up
This information is useful as debug at most.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mostly simple overlapping changes.
For example, David Ahern's adjacency list revamp in 'net-next'
conflicted with an adjacency list traversal bug fix in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit e3f74b841d
("hv_netvsc: report vmbus name in ethtool")'
because of problem introduced by commit f9a56e5d6a0ba
("Drivers: hv: make VMBus bus ids persistent").
This changed the format of the vmbus name and this new format is too
long to fit in the bus_info field of ethtool.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Hyper-V netvsc driver was looking at the incorrect status bits
in the checksum info. It was setting the receive checksum unnecessary
flag based on the IP header checksum being correct. The checksum
flag is skb is about TCP and UDP checksum status. Because of this
bug, any packet received with bad TCP checksum would be passed
up the stack and to the application causing data corruption.
The problem is reproducible via netcat and netem.
This had a side effect of not doing receive checksum offload
on IPv6. The driver was also also always doing checksum offload
independent of the checksum setting done via ethtool.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix in commit 8809883482 ("hv_netvsc: set nvdev link after populating
chn_table") turns out to be incomplete. A crash in
netvsc_get_next_send_section() is observed on mtu change when the device
is under load. The race I identified is: if we get to netvsc_send() after
we set net_device_ctx->nvdev link in netvsc_device_add() but before we
finish netvsc_connect_vsp()->netvsc_init_buf() send_section_map is not
allocated and we crash. Unfortunately we can't set net_device_ctx->nvdev
link after the netvsc_init_buf() call as during the negotiation we need
to receive packets and on the receive path we check for it. It would
probably be possible to split nvdev into a pair of nvdev_in and nvdev_out
links and check them accordingly in get_outbound_net_device()/
get_inbound_net_device() but this looks like an overkill.
Check that send_section_map is allocated in netvsc_send().
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hyperv_net:
- set min/max_mtu, per Haiyang, after rndis_filter_device_add
virtio_net:
- set min/max_mtu
- remove virtnet_change_mtu
vmxnet3:
- set min/max_mtu
xen-netback:
- min_mtu = 0, max_mtu = 65517
xen-netfront:
- min_mtu = 0, max_mtu = 65535
unisys/visor:
- clean up defines a little to not clash with network core or add
redundat definitions
CC: netdev@vger.kernel.org
CC: virtualization@lists.linux-foundation.org
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Shrikrishna Khare <skhare@vmware.com>
CC: "VMware, Inc." <pv-drivers@vmware.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Paul Durrant <paul.durrant@citrix.com>
CC: David Kershner <david.kershner@unisys.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The hdr_offset variable is only if we deal with a TCP or UDP packet,
but as the check surrounding its usage tests for skb_is_gso()
instead, the compiler has no idea if the variable is initialized
or not at that point:
drivers/net/hyperv/netvsc_drv.c: In function ‘netvsc_start_xmit’:
drivers/net/hyperv/netvsc_drv.c:494:42: error: ‘hdr_offset’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
This adds an additional check for the transport type, which
tells the compiler that this path cannot happen. Since the
get_net_transport_info() function should always be inlined
here, I don't expect this to result in additional runtime
checks.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The software calculation of UDP checksum in Netvsc driver was
only handling IPv4 case. By using skb_checksum_help() instead
all protocols can be handled. Rearrange code to eliminate goto
and look like other drivers.
This is a temporary solution; recent versions of Window Server etc
do support UDP checksum offload, just need to do the appropriate negotiation
with host to validate before using. This will be done in later patch.
Please queue this for -stable as well.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Typo's and spelling errors. Also remove old comment from staging era.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Useful for debugging issues with multicast and SR-IOV to keep track
of number of received multicast packets.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since VF reference is now protected by RCU, no longer need the VF usage
counter and can use device flags to see whether to inject or not.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The vf_netdev pointer in the netvsc device context can simply be protected
by RCU because network device destruction is already RCU synchronized.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The code to associate netvsc and VF devices can be made less error prone
by using a better matching algorithms.
On registration, use the permanent address which avoids any possible
issues caused by device MAC address being changed. For all other callbacks,
search by the netdevice pointer value to ensure getting the correct
network device.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The callback handler for netlink events can be simplified:
* Consolidate check for netlink callback events about this driver itself.
* Ignore non-Ethernet devices.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netvsc driver holds a pointer to the virtual function network device if
managing SR-IOV association. In order to ensure that the VF network device
does not disappear, it should be using dev_hold/dev_put to get a reference
count.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Packets that are transmitted in normal path should use consume_skb
instead of kfree_skb. This allows for better tracing of packet drops.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
These functions are used by other code misc-next tree.
This reverts commit 30d1de08c8.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Printing console messages is not helpful when system is out of memory;
and can be disastrous with netconsole. Instead keep statistics
of these anomalous conditions.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make netvsc on vmbus behave more like PCI.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The variable m_ret is only used in one basic block.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Break the different cases, code is cleaner if broken up
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rearrange the transmit routine to eliminate goto's and unnecessary
boolean variables. Use standard functions to test for vlan tag.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move initialization to allocate where other fields are initialized.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't hard code size of array of NDIS versions.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several new functions were introduced into hyperv.h but only used in one file.
Move them and let compiler decide on inline.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix most of the complaints about the style of the code.
Things like extra blank lines and return statements.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Better to use kcalloc rather than kzalloc and multiply for an array.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function get_netvsc_net_device had conditional locking. This was
unnecessary, incorrect, but harmless. It was unnecessary since the
code is only called from netlink netdev event callback where RTNL
is always acquired before the callbacks are run. It was incorrect
because of use of trylock and then continuing.
Fix by replacing with proper assertion.
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The existing code uses busy retry when unable to send out receive
completions due to full ring buffer. It also gives up retrying after limit
is reached, and causes receive buffer slots not being recycled.
This patch implements batching of receive completions. It also prevents
dropping receive completions due to full ring buffer.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor overlapping changes for both merge conflicts.
Resolution work done by Stephen Rothwell was used
as a reference.
Signed-off-by: David S. Miller <davem@davemloft.net>
Bonding driver sets IFF_BONDING on both master (the bonding device) and
slave (the real NIC) devices and in netvsc_netdev_event() we want to skip
master devices only. Currently, there is an uncertainty when a slave
interface is removed: if bonding module comes first in netdev_chain it
clears IFF_BONDING flag on the netdev and netvsc_netdev_event() correctly
handles NETDEV_UNREGISTER event, but in case netvsc comes first on the
chain it sees the device with IFF_BONDING still attached and skips it. As
we still hold vf_netdev pointer to the device we crash on the next inject.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We're not guaranteed to see NETDEV_REGISTER/NETDEV_UNREGISTER notifications
only once per VF but we increase/decrease module refcount unconditionally.
Check vf_netdev to make sure we don't take/release it twice. We presume
that only one VF per netvsc device may exist.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We reset vf_inject on VF going down (netvsc_vf_down()) but we don't on
VF removal (netvsc_unregister_vf()) so vf_inject stays 'true' while
vf_netdev is already NULL and we're trying to inject packets into NULL
net device in netvsc_recv_callback() causing kernel to crash.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Here is a deadlock scenario:
- netvsc_vf_up() schedules netvsc_notify_peers() work and quits.
- netvsc_vf_down() runs before netvsc_notify_peers() gets executed. As it
is being executed from netdev notifier chain we hold rtnl lock when we
get here.
- we enter while (atomic_read(&net_device_ctx->vf_use_cnt) != 0) loop and
wait till netvsc_notify_peers() drops vf_use_cnt.
- netvsc_notify_peers() starts on some other CPU but netdev_notify_peers()
will hang on rtnl_lock().
- deadlock!
Instead of introducing additional synchronization I suggest we drop
gwrk.dwrk completely and call NETDEV_NOTIFY_PEERS directly. As we're
acting under rtnl lock this is legitimate.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct netvsc_device is not suitable for storing VF information as this
structure is being destroyed on MTU change / set channel operation (see
rndis_filter_device_remove()). Move all VF related stuff to struct
net_device_context which is persistent.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On Hyper-V host 2016 and later, VMs gets an event message of the physical
link speed when vSwitch is changed. This patch handles this message, so
the updated link speed can be reported by ethtool.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The physical link speed value will be reported by ethtool command.
The real speed is available from Windows 2016 host or later.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Added a condition to avoid bonding devices with same MAC registering
as VF.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the new APIs for eliminating a copy on the receive path. These new APIs also
help in minimizing the number of memory barriers we end up issuing (in the
ringbuffer code) since we can better control when we want to expose the ring
state to the host.
The patch is being resent to address earlier email issues.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 <vkuznets@redhat.com>
Acked-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The only caller rndis_filter_device_add() has 'struct net_device' pointer
already.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We unpack 'struct net_device' in netvsc_set_mac_addr() to get to
'struct hv_device' pointer which we use in rndis_filter_set_device_mac()
to get back to 'struct net_device'.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Both rndis_filter_open()/rndis_filter_close() use struct hv_device to
reach to struct netvsc_device only and all callers have it already.
While on it, rename net_device to nvdev in rndis_filter_open() as
net_device is misleading.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>