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Author SHA1 Message Date
Linus Torvalds e0c38a4d1f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New ipset extensions for matching on destination MAC addresses, from
    Stefano Brivio.

 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to
    nfp driver. From Stefano Brivio.

 3) Implement GRO for plain UDP sockets, from Paolo Abeni.

 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT
    bit so that we could support the entire vlan_tci value.

 5) Rework the IPSEC policy lookups to better optimize more usecases,
    from Florian Westphal.

 6) Infrastructure changes eliminating direct manipulation of SKB lists
    wherever possible, and to always use the appropriate SKB list
    helpers. This work is still ongoing...

 7) Lots of PHY driver and state machine improvements and
    simplifications, from Heiner Kallweit.

 8) Various TSO deferral refinements, from Eric Dumazet.

 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov.

10) Batch dropping of XDP packets in tuntap, from Jason Wang.

11) Lots of cleanups and improvements to the r8169 driver from Heiner
    Kallweit, including support for ->xmit_more. This driver has been
    getting some much needed love since he started working on it.

12) Lots of new forwarding selftests from Petr Machata.

13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel.

14) Packed ring support for virtio, from Tiwei Bie.

15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov.

16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu.

17) Implement coalescing on TCP backlog queue, from Eric Dumazet.

18) Implement carrier change in tun driver, from Nicolas Dichtel.

19) Support msg_zerocopy in UDP, from Willem de Bruijn.

20) Significantly improve garbage collection of neighbor objects when
    the table has many PERMANENT entries, from David Ahern.

21) Remove egdev usage from nfp and mlx5, and remove the facility
    completely from the tree as it no longer has any users. From Oz
    Shlomo and others.

22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and
    therefore abort the operation before the commit phase (which is the
    NETDEV_CHANGEADDR event). From Petr Machata.

23) Add indirect call wrappers to avoid retpoline overhead, and use them
    in the GRO code paths. From Paolo Abeni.

24) Add support for netlink FDB get operations, from Roopa Prabhu.

25) Support bloom filter in mlxsw driver, from Nir Dotan.

26) Add SKB extension infrastructure. This consolidates the handling of
    the auxiliary SKB data used by IPSEC and bridge netfilter, and is
    designed to support the needs to MPTCP which could be integrated in
    the future.

27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits)
  net: dccp: fix kernel crash on module load
  drivers/net: appletalk/cops: remove redundant if statement and mask
  bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw
  net/net_namespace: Check the return value of register_pernet_subsys()
  net/netlink_compat: Fix a missing check of nla_parse_nested
  ieee802154: lowpan_header_create check must check daddr
  net/mlx4_core: drop useless LIST_HEAD
  mlxsw: spectrum: drop useless LIST_HEAD
  net/mlx5e: drop useless LIST_HEAD
  iptunnel: Set tun_flags in the iptunnel_metadata_reply from src
  net/mlx5e: fix semicolon.cocci warnings
  staging: octeon: fix build failure with XFRM enabled
  net: Revert recent Spectre-v1 patches.
  can: af_can: Fix Spectre v1 vulnerability
  packet: validate address length if non-zero
  nfc: af_nfc: Fix Spectre v1 vulnerability
  phonet: af_phonet: Fix Spectre v1 vulnerability
  net: core: Fix Spectre v1 vulnerability
  net: minor cleanup in skb_ext_add()
  net: drop the unused helper skb_ext_get()
  ...
2018-12-27 13:04:52 -08:00
Linus Torvalds 792bf4d871 Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The biggest RCU changes in this cycle were:

   - Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar.

   - Replace calls of RCU-bh and RCU-sched update-side functions to
     their vanilla RCU counterparts. This series is a step towards
     complete removal of the RCU-bh and RCU-sched update-side functions.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - Documentation updates, including a number of flavor-consolidation
     updates from Joel Fernandes.

   - Miscellaneous fixes.

   - Automate generation of the initrd filesystem used for rcutorture
     testing.

   - Convert spin_is_locked() assertions to instead use lockdep.

     ( Note that some of these conversions are going upstream via their
       respective maintainers. )

   - SRCU updates, especially including a fix from Dennis Krein for a
     bag-on-head-class bug.

   - RCU torture-test updates"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits)
  rcutorture: Don't do busted forward-progress testing
  rcutorture: Use 100ms buckets for forward-progress callback histograms
  rcutorture: Recover from OOM during forward-progress tests
  rcutorture: Print forward-progress test age upon failure
  rcutorture: Print time since GP end upon forward-progress failure
  rcutorture: Print histogram of CB invocation at OOM time
  rcutorture: Print GP age upon forward-progress failure
  rcu: Print per-CPU callback counts for forward-progress failures
  rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings
  rcutorture: Dump grace-period diagnostics upon forward-progress OOM
  rcutorture: Prepare for asynchronous access to rcu_fwd_startat
  torture: Remove unnecessary "ret" variables
  rcutorture: Affinity forward-progress test to avoid housekeeping CPUs
  rcutorture: Break up too-long rcu_torture_fwd_prog() function
  rcutorture: Remove cbflood facility
  torture: Bring any extra CPUs online during kernel startup
  rcutorture: Add call_rcu() flooding forward-progress tests
  rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
  tools/kernel.h: Replace synchronize_sched() with synchronize_rcu()
  net/decnet: Replace rcu_barrier_bh() with rcu_barrier()
  ...
2018-12-26 13:07:19 -08:00
David S. Miller 2be09de7d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.

Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 11:53:36 -08:00
Jason Wang 86a07da343 Revert "net: vhost: lock the vqs one by one"
This reverts commit 78139c94dc. We don't
protect device IOTLB with vq mutex, which will lead e.g use after free
for device IOTLB entries. And since we've switched to use
mutex_trylock() in previous patch, it's safe to revert it without
having deadlock.

Fixes: commit 78139c94dc ("net: vhost: lock the vqs one by one")
Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-12 21:56:20 -08:00
Jason Wang 476e8ba712 vhost_net: switch to use mutex_trylock() in vhost_net_busy_poll()
We used to hold the mutex of paired virtqueue in
vhost_net_busy_poll(). But this will results an inconsistent lock
order which may cause deadlock if we try to bring back the protection
of device IOTLB with vq mutex that requires to hold mutex of all
virtqueues at the same time.

Fix this simply by switching to use mutex_trylock(), when fail just
skip the busy polling. This can happen when device IOTLB is under
updating which should be rare.

Fixes: commit 78139c94dc ("net: vhost: lock the vqs one by one")
Cc: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-12 21:56:19 -08:00
Jason Wang 841df92241 vhost: make sure used idx is seen before log in vhost_add_used_n()
We miss a write barrier that guarantees used idx is updated and seen
before log. This will let userspace sync and copy used ring before
used idx is update. Fix this by adding a barrier before log_write().

Fixes: 8dd014adfe ("vhost-net: mergeable buffers support")
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-12 21:56:19 -08:00
David S. Miller 4cc1feeb6f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several conflicts, seemingly all over the place.

I used Stephen Rothwell's sample resolutions for many of these, if not
just to double check my own work, so definitely the credit largely
goes to him.

The NFP conflict consisted of a bug fix (moving operations
past the rhashtable operation) while chaning the initial
argument in the function call in the moved code.

The net/dsa/master.c conflict had to do with a bug fix intermixing of
making dsa_master_set_mtu() static with the fixing of the tagging
attribute location.

cls_flower had a conflict because the dup reject fix from Or
overlapped with the addition of port range classifiction.

__set_phy_supported()'s conflict was relatively easy to resolve
because Andrew fixed it in both trees, so it was just a matter
of taking the net-next copy.  Or at least I think it was :-)

Joe Stringer's fix to the handling of netns id 0 in bpf_sk_lookup()
intermixed with changes on how the sdif and caller_net are calculated
in these code paths in net-next.

The remaining BPF conflicts were largely about the addition of the
__bpf_md_ptr stuff in 'net' overlapping with adjustments and additions
to the relevant data structure where the MD pointer macros are used.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-09 21:43:31 -08:00
Linus Torvalds d48f782e4f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "A decent batch of fixes here. I'd say about half are for problems that
  have existed for a while, and half are for new regressions added in
  the 4.20 merge window.

   1) Fix 10G SFP phy module detection in mvpp2, from Baruch Siach.

   2) Revert bogus emac driver change, from Benjamin Herrenschmidt.

   3) Handle BPF exported data structure with pointers when building
      32-bit userland, from Daniel Borkmann.

   4) Memory leak fix in act_police, from Davide Caratti.

   5) Check RX checksum offload in RX descriptors properly in aquantia
      driver, from Dmitry Bogdanov.

   6) SKB unlink fix in various spots, from Edward Cree.

   7) ndo_dflt_fdb_dump() only works with ethernet, enforce this, from
      Eric Dumazet.

   8) Fix FID leak in mlxsw driver, from Ido Schimmel.

   9) IOTLB locking fix in vhost, from Jean-Philippe Brucker.

  10) Fix SKB truesize accounting in ipv4/ipv6/netfilter frag memory
      limits otherwise namespace exit can hang. From Jiri Wiesner.

  11) Address block parsing length fixes in x25 from Martin Schiller.

  12) IRQ and ring accounting fixes in bnxt_en, from Michael Chan.

  13) For tun interfaces, only iface delete works with rtnl ops, enforce
      this by disallowing add. From Nicolas Dichtel.

  14) Use after free in liquidio, from Pan Bian.

  15) Fix SKB use after passing to netif_receive_skb(), from Prashant
      Bhole.

  16) Static key accounting and other fixes in XPS from Sabrina Dubroca.

  17) Partially initialized flow key passed to ip6_route_output(), from
      Shmulik Ladkani.

  18) Fix RTNL deadlock during reset in ibmvnic driver, from Thomas
      Falcon.

  19) Several small TCP fixes (off-by-one on window probe abort, NULL
      deref in tail loss probe, SNMP mis-estimations) from Yuchung
      Cheng"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (93 commits)
  net/sched: cls_flower: Reject duplicated rules also under skip_sw
  bnxt_en: Fix _bnxt_get_max_rings() for 57500 chips.
  bnxt_en: Fix NQ/CP rings accounting on the new 57500 chips.
  bnxt_en: Keep track of reserved IRQs.
  bnxt_en: Fix CNP CoS queue regression.
  net/mlx4_core: Correctly set PFC param if global pause is turned off.
  Revert "net/ibm/emac: wrong bit is used for STA control"
  neighbour: Avoid writing before skb->head in neigh_hh_output()
  ipv6: Check available headroom in ip6_xmit() even without options
  tcp: lack of available data can also cause TSO defer
  ipv6: sr: properly initialize flowi6 prior passing to ip6_route_output
  mlxsw: spectrum_switchdev: Fix VLAN device deletion via ioctl
  mlxsw: spectrum_router: Relax GRE decap matching check
  mlxsw: spectrum_switchdev: Avoid leaking FID's reference count
  mlxsw: spectrum_nve: Remove easily triggerable warnings
  ipv4: ipv6: netfilter: Adjust the frag mem limit when truesize changes
  sctp: frag_point sanity check
  tcp: fix NULL ref in tail loss probe
  tcp: Do not underestimate rwnd_limited
  net: use skb_list_del_init() to remove from RX sublists
  ...
2018-12-09 15:12:33 -08:00
Stefan Hajnoczi 834e772c8d vhost/vsock: fix use-after-free in network stack callers
If the network stack calls .send_pkt()/.cancel_pkt() during .release(),
a struct vhost_vsock use-after-free is possible.  This occurs because
.release() does not wait for other CPUs to stop using struct
vhost_vsock.

Switch to an RCU-enabled hashtable (indexed by guest CID) so that
.release() can wait for other CPUs by calling synchronize_rcu().  This
also eliminates vhost_vsock_lock acquisition in the data path so it
could have a positive effect on performance.

This is CVE-2018-14625 "kernel: use-after-free Read in vhost_transport_send_pkt".

Cc: stable@vger.kernel.org
Reported-and-tested-by: syzbot+bd391451452fb0b93039@syzkaller.appspotmail.com
Reported-by: syzbot+e3e074963495f92a89ed@syzkaller.appspotmail.com
Reported-by: syzbot+d5a0a170c5069658b141@syzkaller.appspotmail.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2018-12-06 14:28:38 -05:00
Stefan Hajnoczi c38f57da42 vhost/vsock: fix reset orphans race with close timeout
If a local process has closed a connected socket and hasn't received a
RST packet yet, then the socket remains in the table until a timeout
expires.

When a vhost_vsock instance is released with the timeout still pending,
the socket is never freed because vhost_vsock has already set the
SOCK_DONE flag.

Check if the close timer is pending and let it close the socket.  This
prevents the race which can leak sockets.

Reported-by: Maximilian Riemensberger <riemensberger@cadami.net>
Cc: Graham Whaley <graham.whaley@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-12-06 14:22:34 -05:00
Jean-Philippe Brucker e3f787189e vhost: fix IOTLB locking
Commit 78139c94dc ("net: vhost: lock the vqs one by one") moved the vq
lock to improve scalability, but introduced a possible deadlock in
vhost-iotlb. vhost_iotlb_notify_vq() now takes vq->mutex while holding
the device's IOTLB spinlock. And on the vhost_iotlb_miss() path, the
spinlock is taken while holding vq->mutex.

Since calling vhost_poll_queue() doesn't require any lock, avoid the
deadlock by not taking vq->mutex.

Fixes: 78139c94dc ("net: vhost: lock the vqs one by one")
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-03 15:52:30 -08:00
Paul E. McKenney d05faa5f1a drivers/vhost: Replace synchronize_rcu_bh() with synchronize_rcu()
Now that synchronize_rcu() waits for bh-disable regions of code as well
as RCU read-side critical sections, synchronize_rcu_bh() can be replaced
by synchronize_rcu().  This commit therefore makes this change.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: <kvm@vger.kernel.org>
Cc: <virtualization@lists.linux-foundation.org>
Cc: <netdev@vger.kernel.org>
2018-11-27 09:21:37 -08:00
Jason Wang e4dab1e6ea vhost_net: mitigate page reference counting during page frag refill
We do a get_page() which involves a atomic operation. This patch tries
to mitigate a per packet atomic operation by maintaining a reference
bias which is initially USHRT_MAX. Each time a page is got, instead of
calling get_page() we decrease the bias and when we find it's time to
use a new page we will decrease the bias at one time through
__page_cache_drain_cache().

Testpmd(virtio_user + vhost_net) + XDP_DROP on TAP shows about 1.6%
improvement.

Before: 4.63Mpps
After:  4.71Mpps

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-17 12:00:42 -08:00
Linus Torvalds b5b1de3537 virtio, vhost: fixes, tweaks
virtio balloon page hinting support
 vhost scsi control queue
 
 misc fixes.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio/vhost updates from Michael Tsirkin:
 "Fixes and tweaks:

   - virtio balloon page hinting support

   - vhost scsi control queue

   - misc fixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  MAINTAINERS: remove reference to bogus vsock file
  vhost/scsi: Use common handling code in request queue handler
  vhost/scsi: Extract common handling code from control queue handler
  vhost/scsi: Respond to control queue operations
  vhost/scsi: truncate T10 PI iov_iter to prot_bytes
  virtio-balloon: VIRTIO_BALLOON_F_PAGE_POISON
  mm/page_poison: expose page_poisoning_enabled to kernel modules
  virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT
  kvm_config: add CONFIG_VIRTIO_MENU
2018-11-01 14:42:49 -07:00
Jason Wang ff002269a4 vhost: Fix Spectre V1 vulnerability
The idx in vhost_vring_ioctl() was controlled by userspace, hence a
potential exploitation of the Spectre variant 1 vulnerability.

Fixing this by sanitizing idx before using it to index d->vqs.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-31 12:39:15 -07:00
Bijan Mottahedeh 09d7583294 vhost/scsi: Use common handling code in request queue handler
Change the request queue handler to use common handling routines same
as the control queue handler.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 21:16:13 -04:00
Bijan Mottahedeh 3f8ca2e115 vhost/scsi: Extract common handling code from control queue handler
Prepare to change the request queue handler to use common handling
routines.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 21:16:13 -04:00
Bijan Mottahedeh 0d02dbd68c vhost/scsi: Respond to control queue operations
The vhost-scsi driver currently does not handle any control queue
operations. In particular, vhost_scsi_ctl_handle_kick, merely prints out
a debug message but does nothing else. This can cause guest VMs to hang.

As part of SCSI recovery from an error, e.g., an I/O timeout, the SCSI
midlayer attempts to abort the failed operation. The SCSI virtio driver
translates the abort to a SCSI TMF request that gets put on the control
queue (virtscsi_abort -> virtscsi_tmf). The SCSI virtio driver then
waits indefinitely for this request to be completed, but it never will
because vhost-scsi never responds to that request.

To avoid a hang, always respond to control queue operations; explicitly
reject TMF requests, and return a no-op response to event requests.

Signed-off-by: Bijan Mottahedeh <bijan.mottahedeh@oracle.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-10-24 21:16:13 -04:00
Greg Edwards 4542d623c7 vhost/scsi: truncate T10 PI iov_iter to prot_bytes
Commands with protection information included were not truncating the
protection iov_iter to the number of protection bytes in the command.
This resulted in vhost_scsi mis-calculating the size of the protection
SGL in vhost_scsi_calc_sgls(), and including both the protection and
data SG entries in the protection SGL.

Fixes: 09b13fa8c1 ("vhost/scsi: Add ANY_LAYOUT support in vhost_scsi_handle_vq")
Signed-off-by: Greg Edwards <gedwards@ddn.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Fixes: 09b13fa8c1
Cc: stable@vger.kernel.org
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-24 21:16:13 -04:00
Tonghao Zhang abf1a08ff3 net: vhost: remove bad code line
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-07 21:31:32 -07:00
Tonghao Zhang 441abde4cd net: vhost: add rx busy polling in tx path
This patch improves the guest receive performance.
On the handle_tx side, we poll the sock receive queue at the
same time. handle_rx do that in the same way.

We set the poll-us=100us and use the netperf to test throughput
and mean latency. When running the tests, the vhost-net kthread
of that VM, is alway 100% CPU. The commands are shown as below.

Rx performance is greatly improved by this patch. There is not
notable performance change on tx with this series though. This
patch is useful for bi-directional traffic.

netperf -H IP -t TCP_STREAM -l 20 -- -O "THROUGHPUT, THROUGHPUT_UNITS, MEAN_LATENCY"

Topology:
[Host] ->linux bridge -> tap vhost-net ->[Guest]

TCP_STREAM:
* Without the patch:  19842.95 Mbps, 6.50 us mean latency
* With the patch:     37598.20 Mbps, 3.43 us mean latency

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:25:55 -07:00
Tonghao Zhang dc151282bb net: vhost: factor out busy polling logic to vhost_net_busy_poll()
Factor out generic busy polling logic and will be
used for in tx path in the next patch. And with the patch,
qemu can set differently the busyloop_timeout for rx queue.

To avoid duplicate codes, introduce the helper functions:
* sock_has_rx_data(changed from sk_has_rx_data)
* vhost_net_busy_poll_try_queue

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:25:55 -07:00
Tonghao Zhang a6a67a2f34 net: vhost: replace magic number of lock annotation
Use the VHOST_NET_VQ_XXX as a subclass for mutex_lock_nested.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:25:55 -07:00
Tonghao Zhang 78139c94dc net: vhost: lock the vqs one by one
This patch changes the way that lock all vqs
at the same, to lock them one by one. It will
be used for next patch to avoid the deadlock.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:25:54 -07:00
Dan Carpenter 8a1aff144d vhost_net: add a missing error return
We accidentally left out this error return so it leads to some use after
free bugs later on.

Fixes: 0a0be13b8f ("vhost_net: batch submitting XDP buffers to underlayer sockets")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-21 09:05:57 -07:00
Jason Wang 0a0be13b8f vhost_net: batch submitting XDP buffers to underlayer sockets
This patch implements XDP batching for vhost_net. The idea is first to
try to do userspace copy and build XDP buff directly in vhost. Instead
of submitting the packet immediately, vhost_net will batch them in an
array and submit every 64 (VHOST_NET_BATCH) packets to the under layer
sockets through msg_control of sendmsg().

When XDP is enabled on the TUN/TAP, TUN/TAP can process XDP inside a
loop without caring GUP thus it can do batch map flushing. When XDP is
not enabled or not supported, the underlayer socket need to build skb
and pass it to network core. The batched packet submission allows us
to do batching like netif_receive_skb_list() in the future.

This saves lots of indirect calls for better cache utilization. For
the case that we can't so batching e.g when sndbuf is limited or
packet size is too large, we will go for usual one packet per
sendmsg() way.

Doing testpmd on various setups gives us:

Test                /+pps%
XDP_DROP on TAP     /+44.8%
XDP_REDIRECT on TAP /+29%
macvtap (skb)       /+26%

Netperf tests shows obvious improvements for small packet transmission:

size/session/+thu%/+normalize%
   64/     1/   +2%/    0%
   64/     2/   +3%/   +1%
   64/     4/   +7%/   +5%
   64/     8/   +8%/   +6%
  256/     1/   +3%/    0%
  256/     2/  +10%/   +7%
  256/     4/  +26%/  +22%
  256/     8/  +27%/  +23%
  512/     1/   +3%/   +2%
  512/     2/  +19%/  +14%
  512/     4/  +43%/  +40%
  512/     8/  +45%/  +41%
 1024/     1/   +4%/    0%
 1024/     2/  +27%/  +21%
 1024/     4/  +38%/  +73%
 1024/     8/  +15%/  +24%
 2048/     1/  +10%/   +7%
 2048/     2/  +16%/  +12%
 2048/     4/    0%/   +2%
 2048/     8/    0%/   +2%
 4096/     1/  +36%/  +60%
 4096/     2/  -11%/  -26%
 4096/     4/    0%/  +14%
 4096/     8/    0%/   +4%
16384/     1/   -1%/   +5%
16384/     2/    0%/   +2%
16384/     4/    0%/   -3%
16384/     8/    0%/   +4%
65535/     1/    0%/  +10%
65535/     2/    0%/   +8%
65535/     4/    0%/   +1%
65535/     8/    0%/   +3%

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-13 09:25:41 -07:00
Jason Wang fe8dd45bb7 tun: switch to new type of msg_control
This patch introduces to a new tun/tap specific msg_control:

#define TUN_MSG_UBUF 1
#define TUN_MSG_PTR  2
struct tun_msg_ctl {
       int type;
       void *ptr;
};

This allows us to pass different kinds of msg_control through
sendmsg(). The first supported type is ubuf (TUN_MSG_UBUF) which will
be used by the existed vhost_net zerocopy code. The second is XDP
buff, which allows vhost_net to pass XDP buff to TUN. This could be
used to implement accepting an array of XDP buffs from vhost_net in
the following patches.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-13 09:25:40 -07:00
Linus Torvalds 050cdc6c95 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) ICE, E1000, IGB, IXGBE, and I40E bug fixes from the Intel folks.

 2) Better fix for AB-BA deadlock in packet scheduler code, from Cong
    Wang.

 3) bpf sockmap fixes (zero sized key handling, etc.) from Daniel
    Borkmann.

 4) Send zero IPID in TCP resets and SYN-RECV state ACKs, to prevent
    attackers using it as a side-channel. From Eric Dumazet.

 5) Memory leak in mediatek bluetooth driver, from Gustavo A. R. Silva.

 6) Hook up rt->dst.input of ipv6 anycast routes properly, from Hangbin
    Liu.

 7) hns and hns3 bug fixes from Huazhong Tan.

 8) Fix RIF leak in mlxsw driver, from Ido Schimmel.

 9) iova range check fix in vhost, from Jason Wang.

10) Fix hang in do_tcp_sendpages() with tls, from John Fastabend.

11) More r8152 chips need to disable RX aggregation, from Kai-Heng Feng.

12) Memory exposure in TCA_U32_SEL handling, from Kees Cook.

13) TCP BBR congestion control fixes from Kevin Yang.

14) hv_netvsc, ignore non-PCI devices, from Stephen Hemminger.

15) qed driver fixes from Tomer Tayar.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
  net: sched: Fix memory exposure from short TCA_U32_SEL
  qed: fix spelling mistake "comparsion" -> "comparison"
  vhost: correctly check the iova range when waking virtqueue
  qlge: Fix netdev features configuration.
  net: macb: do not disable MDIO bus at open/close time
  Revert "net: stmmac: fix build failure due to missing COMMON_CLK dependency"
  net: macb: Fix regression breaking non-MDIO fixed-link PHYs
  mlxsw: spectrum_switchdev: Do not leak RIFs when removing bridge
  i40e: fix condition of WARN_ONCE for stat strings
  i40e: Fix for Tx timeouts when interface is brought up if DCB is enabled
  ixgbe: fix driver behaviour after issuing VFLR
  ixgbe: Prevent unsupported configurations with XDP
  ixgbe: Replace GFP_ATOMIC with GFP_KERNEL
  igb: Replace mdelay() with msleep() in igb_integrated_phy_loopback()
  igb: Replace GFP_ATOMIC with GFP_KERNEL in igb_sw_init()
  igb: Use an advanced ctx descriptor for launchtime
  e1000: ensure to free old tx/rx rings in set_ringparam()
  e1000: check on netif_running() before calling e1000_up()
  ixgb: use dma_zalloc_coherent instead of allocator/memset
  ice: Trivial formatting fixes
  ...
2018-08-27 11:59:39 -07:00
Jason Wang 2d66f997f0 vhost: correctly check the iova range when waking virtqueue
We don't wakeup the virtqueue if the first byte of pending iova range
is the last byte of the range we just got updated. This will lead a
virtqueue to wait for IOTLB updating forever. Fixing by correct the
check and wake up the virtqueue in this case.

Fixes: 6b1e6cc785 ("vhost: new device IOTLB API")
Reported-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-25 17:39:41 -07:00
Linus Torvalds d002924f93 virtio, vhost: fixes, tweaks
No new features but a bunch of tweaks such as
 switching balloon from oom notifier to shrinker.
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "virtio, vhost: fixes, tweaks

  No new features but a bunch of tweaks such as switching balloon from
  oom notifier to shrinker"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost/scsi: increase VHOST_SCSI_PREALLOC_PROT_SGLS to 2048
  vhost: allow vhost-scsi driver to be built-in
  virtio: pci-legacy: Validate queue pfn
  virtio: mmio-v1: Validate queue PFN
  virtio_balloon: replace oom notifier with shrinker
  virtio-balloon: kzalloc the vb struct
  virtio-balloon: remove BUG() in init_vqs
2018-08-24 08:45:19 -07:00
Greg Edwards 864d39df09 vhost/scsi: increase VHOST_SCSI_PREALLOC_PROT_SGLS to 2048
The current value of VHOST_SCSI_PREALLOC_PROT_SGLS is too small to
accommodate larger I/Os, e.g. 16-32 MiB, when the VIRTIO_SCSI_F_T10_PI
feature bit is negotiated and the backing store supports T10 PI.

vhost-scsi rejects the command with errors like:

[   59.581317] vhost_scsi_calc_sgls: requested sgl_count: 1820 exceeds pre-allocated max_sgls: 512

Signed-off-by: Greg Edwards <gedwards@ddn.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 01:01:47 +03:00
Greg Edwards 84f3396b71 vhost: allow vhost-scsi driver to be built-in
It's useful to allow vhost-scsi to be built-in when testing vhost in L1
+ L2 VMs and booting L1 VM with QEMU '-kernel' option.

Signed-off-by: Greg Edwards <gedwards@ddn.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-08-22 01:01:32 +03:00
Linus Torvalds 72f02ba66b SCSI misc on 20180815
This is mostly updates to the usual drivers: mpt3sas, lpfc, qla2xxx,
 hisi_sas, smartpqi, megaraid_sas, arcmsr.  In addition, with the
 continuing absence of Nic we have target updates for tcmu and target
 core (all with reviews and acks).  The biggest observable change is
 going to be that we're (again) trying to switch to mulitqueue as the
 default (a user can still override the setting on the kernel command
 line).  Other major core stuff is the removal of the remaining
 Microchannel drivers, an update of the internal timers and some
 reworks of completion and result handling.
 
 Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is mostly updates to the usual drivers: mpt3sas, lpfc, qla2xxx,
  hisi_sas, smartpqi, megaraid_sas, arcmsr.

  In addition, with the continuing absence of Nic we have target updates
  for tcmu and target core (all with reviews and acks).

  The biggest observable change is going to be that we're (again) trying
  to switch to mulitqueue as the default (a user can still override the
  setting on the kernel command line).

  Other major core stuff is the removal of the remaining Microchannel
  drivers, an update of the internal timers and some reworks of
  completion and result handling"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (203 commits)
  scsi: core: use blk_mq_run_hw_queues in scsi_kick_queue
  scsi: ufs: remove unnecessary query(DM) UPIU trace
  scsi: qla2xxx: Fix issue reported by static checker for qla2x00_els_dcmd2_sp_done()
  scsi: aacraid: Spelling fix in comment
  scsi: mpt3sas: Fix calltrace observed while running IO & reset
  scsi: aic94xx: fix an error code in aic94xx_init()
  scsi: st: remove redundant pointer STbuffer
  scsi: qla2xxx: Update driver version to 10.00.00.08-k
  scsi: qla2xxx: Migrate NVME N2N handling into state machine
  scsi: qla2xxx: Save frame payload size from ICB
  scsi: qla2xxx: Fix stalled relogin
  scsi: qla2xxx: Fix race between switch cmd completion and timeout
  scsi: qla2xxx: Fix Management Server NPort handle reservation logic
  scsi: qla2xxx: Flush mailbox commands on chip reset
  scsi: qla2xxx: Fix unintended Logout
  scsi: qla2xxx: Fix session state stuck in Get Port DB
  scsi: qla2xxx: Fix redundant fc_rport registration
  scsi: qla2xxx: Silent erroneous message
  scsi: qla2xxx: Prevent sysfs access when chip is down
  scsi: qla2xxx: Add longer window for chip reset
  ...
2018-08-15 22:06:26 -07:00
David S. Miller a736e07468 Merge ra.kernel.org:/pub/scm/linux/kernel/git/davem/net
Overlapping changes in RXRPC, changing to ktime_get_seconds() whilst
adding some tracepoints.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-09 11:52:36 -07:00
Jason Wang b13f9c6364 vhost: reset metadata cache when initializing new IOTLB
We need to reset metadata cache during new IOTLB initialization,
otherwise the stale pointers to previous IOTLB may be still accessed
which will lead a use after free.

Reported-by: syzbot+c51e6736a1bf614b3272@syzkaller.appspotmail.com
Fixes: f889491380 ("vhost: introduce O(1) vq metadata cache")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-08 09:44:39 -07:00
Jason Wang 429711aec2 vhost: switch to use new message format
We use to have message like:

struct vhost_msg {
	int type;
	union {
		struct vhost_iotlb_msg iotlb;
		__u8 padding[64];
	};
};

Unfortunately, there will be a hole of 32bit in 64bit machine because
of the alignment. This leads a different formats between 32bit API and
64bit API. What's more it will break 32bit program running on 64bit
machine.

So fixing this by introducing a new message type with an explicit
32bit reserved field after type like:

struct vhost_msg_v2 {
	__u32 type;
	__u32 reserved;
	union {
		struct vhost_iotlb_msg iotlb;
		__u8 padding[64];
	};
};

We will have a consistent ABI after switching to use this. To enable
this capability, introduce a new ioctl (VHOST_SET_BAKCEND_FEATURE) for
userspace to enable this feature (VHOST_BACKEND_F_IOTLB_V2).

Fixes: 6b1e6cc785 ("vhost: new device IOTLB API")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-06 10:41:04 -07:00
Mike Christie 25b88550b7 scsi: target: loop, usb, vhost, xen: use target_remove_session
This converts drivers that were only calling transport_deregister_session
to use target_remove_session. The calling of
transport_deregister_session_configfs via target_remove_session for these
types of drivers is ok, because they were not exporting info from fields
like sess_acl_list, sess->se_tpg and sess->fabric_sess_ptr from configfs
accessible functions, so they will see no difference.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-08-02 15:29:31 -04:00
Mike Christie fa83428730 scsi: target: rename target_alloc_session
Rename target_alloc_session to target_setup_session to avoid confusion with
the other transport session allocation function that only allocates the
session and because the target_alloc_session does so much more. It
allocates the session, sets up the nacl and registers the session.

The next patch will then add a remove function to match the setup in this
one, so it should make sense for all drivers, except iscsi, to just call
those 2 functions to setup and remove a session.

iscsi will continue to be the odd driver.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Chris Boot <bootc@bootc.net>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: Michael Cyr <mikecyr@linux.vnet.ibm.com>
Cc: <qla2xxx-upstream@qlogic.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-08-02 15:29:31 -04:00
Jason Wang 4afb52c2af vhost_net: batch update used ring for datacopy TX
Like commit e2b3b35eb9 ("vhost_net: batch used ring update in rx"),
this patches implements batch used ring update for datacopy TX
(zerocopy has already done some kind of batching).

Testpmd transmission from guest to host (XDP_DROP on tap) shows 25.8%
improvement (from ~3.1Mpps to ~3.9Mpps) on Broadwell i7-5600U CPU @
2.60GHz machine. Netperf TCP tests does not show obvious differences.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang d0d8697187 vhost_net: rename VHOST_RX_BATCH to VHOST_NET_BATCH
A more generic name which could be used for TX as well.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang 09c3248938 vhost_net: rename vhost_rx_signal_used() to vhost_net_signal_used()
Rename for reusing this for TX.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang 0d20bdf34d vhost_net: split out datacopy logic
Instead of mixing zerocopy and datacopy logics, this patch tries to
split datacopy logic out. This results for a more compact code and
ad-hoc optimization could be done on top more easily.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang c92a8a8cb7 vhost_net: introduce tx_can_batch()
Introduce tx_can_batch() to determine whether TX could be
batched. This will help to reduce the code duplication in the future.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang a2a91a137a vhost_net: introduce get_tx_bufs()
Factor out logic of getting tx buffer and iov iter
initialization. This will be used for reducing codes duplication in
the future.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:31 -07:00
Jason Wang 272f35cba5 vhost_net: introduce vhost_exceeds_weight()
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:30 -07:00
Jason Wang b0d0ea50e7 vhost_net: introduce helper to initialize tx iov iter
Introduce init_iov_iter() in order to be reused by future patch.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:30 -07:00
Jason Wang 652e4f3e82 vhost_net: drop unnecessary parameter
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 09:43:30 -07:00
Toshiaki Makita 6369fec5be vhost_net: Avoid rx vring kicks during busyloop
We may run out of avail rx ring descriptor under heavy load but busypoll
did not detect it so busypoll may have exited prematurely. Avoid this by
checking rx ring full during busypoll.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04 21:30:47 +09:00
Toshiaki Makita be294a51ad vhost_net: Avoid rx queue wake-ups during busypoll
We may run handle_rx() while rx work is queued. For example a packet can
push the rx work during the window before handle_rx calls
vhost_net_disable_vq().
In that case busypoll immediately exits due to vhost_has_work()
condition and enables vq again. This can lead to another unnecessary rx
wake-ups, so poll rx work instead of enabling the vq.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04 21:30:46 +09:00
Toshiaki Makita 027b17603b vhost_net: Avoid tx vring kicks during busyloop
Under heavy load vhost busypoll may run without suppressing
notification. For example tx zerocopy callback can push tx work while
handle_tx() is running, then busyloop exits due to vhost_has_work()
condition and enables notification but immediately reenters handle_tx()
because the pushed work was tx. In this case handle_tx() tries to
disable notification again, but when using event_idx it by design
cannot. Then busyloop will run without suppressing notification.
Another example is the case where handle_tx() tries to enable
notification but avail idx is advanced so disables it again. This case
also leads to the same situation with event_idx.

The problem is that once we enter this situation busyloop does not work
under heavy load for considerable amount of time, because notification
is likely to happen during busyloop and handle_tx() immediately enables
notification after notification happens. Specifically busyloop detects
notification by vhost_has_work() and then handle_tx() calls
vhost_enable_notify(). Because the detected work was the tx work, it
enters handle_tx(), and enters busyloop without suppression again.
This is likely to be repeated, so with event_idx we are almost not able
to suppress notification in this case.

To fix this, poll the work instead of enabling notification when
busypoll is interrupted by something. IMHO vhost_has_work() is kind of
interruption rather than a signal to completely cancel the busypoll, so
let's run busypoll after the necessary work is done.

Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04 21:30:46 +09:00