Commit Graph

629 Commits

Author SHA1 Message Date
Michael S. Tsirkin
d085eb8ce7 vhost: disable for OABI
vhost is currently broken on the some ARM configs.

The reason is that the ring element addresses are passed between
components with different alignments assumptions. Thus, if
guest selects a pointer and host then gets and dereferences
it, then alignment assumed by the host's compiler might be
greater than the actual alignment of the pointer.
compiler on the host from assuming pointer is aligned.

This actually triggers on ARM with -mabi=apcs-gnu - which is a
deprecated configuration. With this OABI, compiler assumes that
all structures are 4 byte aligned - which is stronger than
virtio guarantees for available and used rings, which are
merely 2 bytes. Thus a guest without -mabi=apcs-gnu running
on top of host with -mabi=apcs-gnu will be broken.

The correct fix is to force alignment of structures - however
that is an intrusive fix that's best deferred until the next release.

We didn't previously support such ancient systems at all - this surfaced
after vdpa support prompted removing dependency of vhost on
VIRTULIZATION. So for now, let's just add something along the lines of

	depends on !ARM || AEABI

to the virtio Kconfig declaration, and add a comment that it has to do
with struct member alignment.

Note: we can't make VHOST and VHOST_RING themselves have
a dependency since these are selected. Add a new symbol for that.

We should be able to drop this dependency down the road.

Fixes: 20c384f1ea ("vhost: refine vhost and vringh kconfig")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-20 10:19:22 -04:00
Michael S. Tsirkin
58ad13729a vdpa: make vhost, virtio depend on menu
If user did not configure any vdpa drivers, neither vhost
nor virtio vdpa are going to be useful. So there's no point
in prompting for these and selecting vdpa core automatically.
Simplify configuration by making virtio and vhost vdpa
drivers depend on vdpa menu entry. Once done, we no longer
need a separate menu entry, so also get rid of this.
While at it, fix up the IFC entry: VDPA->vDPA for consistency
with other places.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-17 06:05:30 -04:00
Michael S. Tsirkin
3302363a27 virtio/test: fix up after IOTLB changes
Allow building vringh without IOTLB (that's the case for userspace
builds, will be useful for CAIF/VOD down the road too).
Update for API tweaks.
Don't include vringh with userspace builds.

Cc: Jason Wang <jasowang@redhat.com>
Cc: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-16 18:31:08 -04:00
Eugenio Pérez
247643f857 vhost: Create accessors for virtqueues private_data
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Link: https://lore.kernel.org/r/20200331192804.6019-2-eperezma@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-16 18:31:07 -04:00
Jason Yan
e373f3d78d vhost: remove set but not used variable 'status'
Fix the following gcc warning:
drivers/vhost/vdpa.c:299:5: warning: variable 'status' set but not used [-Wunused-but-set-variable]
  u8 status;
     ^~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200402065106.20108-1-yanaijie@huawei.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-16 18:31:03 -04:00
Gustavo A. R. Silva
aa21c2e73e vhost: vdpa: remove unnecessary null check
container_of is never null, so this null check is
unnecessary.

Addresses-Coverity-ID: 1492006 ("Logically dead code")
Fixes: 20453a45fb06 ("vhost: introduce vDPA-based backend")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Link: https://lore.kernel.org/r/20200330235040.GA9997@embeddedor
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-16 18:31:02 -04:00
Tiwei Bie
4c8cf31885 vhost: introduce vDPA-based backend
This patch introduces a vDPA-based vhost backend. This backend is
built on top of the same interface defined in virtio-vDPA and provides
a generic vhost interface for userspace to accelerate the virtio
devices in guest.

This backend is implemented as a vDPA device driver on top of the same
ops used in virtio-vDPA. It will create char device entry named
vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls
on top of this char device to setup the backend.

Vhost ioctls are extended to make it type agnostic and behave like a
virtio device, this help to eliminate type specific API like what
vhost_net/scsi/vsock did:

- VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined
  by virtio specification to differ from different type of devices
- VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue
  supported by the vDPA device
- VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device
- VHOST_VDPA_SET/GET_CONFIG: access virtio config space
- VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue

For memory mapping, IOTLB API is mandated for vhost-vDPA which means
userspace drivers are required to use
VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for
a specific userspace memory region.

The vhost-vDPA API is designed to be type agnostic, but it allows net
device only in current stage. Due to the lacking of control virtqueue
support, some features were filter out by vhost-vdpa.

We will enable more features and devices in the near future.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-8-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-02 10:41:40 -04:00
Jason Wang
9ad9c49cfe vringh: IOTLB support
This patch implements the third memory accessor for vringh besides
current kernel and userspace accessors. This idea is to allow vringh
to do the address translation through an IOTLB which is implemented
via vhost_map interval tree. Users should setup and IOVA to PA mapping
in this IOTLB.

This allows us to:

- Use vringh to access virtqueues with vIOMMU
- Use vringh to implement software virtqueues for vDPA devices

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-5-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
Jason Wang
0bbe30668d vhost: factor out IOTLB
This patch factors out IOTLB into a dedicated module in order to be
reused by other modules like vringh. User may choose to enable the
automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit
for the case of vhost device IOTLB implementation.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
Jason Wang
792a4f2ed2 vhost: allow per device message handler
This patch allow device to register its own message handler during
vhost_dev_init(). vDPA device will use it to implement its own DMA
mapping logic.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-3-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
Jason Wang
20c384f1ea vhost: refine vhost and vringh kconfig
Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is
not necessarily for VM since it's a generic userspace and kernel
communication protocol. Such dependency may prevent archs without
virtualization support from using vhost.

To solve this, a dedicated vhost menu is created under drivers so
CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION.

While at it, also squash Kconfig.vringh into vhost Kconfig file. This
avoids the trick of conditional inclusion from VOP or CAIF. Then it
will be easier to introduce new vringh users and common dependency for
both vringh and vhost.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-01 12:06:26 -04:00
Eugenio Pérez
42d84c8490 vhost: Check docket sk_family instead of call getname
Doing so, we save one call to get data we already have in the struct.

Also, since there is no guarantee that getname use sockaddr_ll
parameter beyond its size, we add a little bit of security here.
It should do not do beyond MAX_ADDR_LEN, but syzbot found that
ax25_getname writes more (72 bytes, the size of full_sockaddr_ax25,
versus 20 + 32 bytes of sockaddr_ll + MAX_ADDR_LEN in syzbot repro).

Fixes: 3a4d5c94e9 ("vhost_net: a kernel-level virtio server")
Reported-by: syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-22 21:41:42 -08:00
Linus Torvalds
95e6ba5133 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from David Miller:

 1) More jumbo frame fixes in r8169, from Heiner Kallweit.

 2) Fix bpf build in minimal configuration, from Alexei Starovoitov.

 3) Use after free in slcan driver, from Jouni Hogander.

 4) Flower classifier port ranges don't work properly in the HW offload
    case, from Yoshiki Komachi.

 5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin.

 6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk.

 7) Fix flow dissection in dsa TX path, from Alexander Lobakin.

 8) Stale syncookie timestampe fixes from Guillaume Nault.

[ Did an evil merge to silence a warning introduced by this pull - Linus ]

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
  r8169: fix rtl_hw_jumbo_disable for RTL8168evl
  net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add()
  r8169: add missing RX enabling for WoL on RTL8125
  vhost/vsock: accept only packets with the right dst_cid
  net: phy: dp83867: fix hfs boot in rgmii mode
  net: ethernet: ti: cpsw: fix extra rx interrupt
  inet: protect against too small mtu values.
  gre: refetch erspan header from skb->data after pskb_may_pull()
  pppoe: remove redundant BUG_ON() check in pppoe_pernet
  tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
  tcp: tighten acceptance of ACKs not matching a child socket
  tcp: fix rejected syncookies due to stale timestamps
  lpc_eth: kernel BUG on remove
  tcp: md5: fix potential overestimation of TCP option space
  net: sched: allow indirect blocks to bind to clsact in TC
  net: core: rename indirect block ingress cb function
  net-sysfs: Call dev_hold always in netdev_queue_add_kobject
  net: dsa: fix flow dissection on Tx path
  net/tls: Fix return values to avoid ENOTSUPP
  net: avoid an indirect call in ____sys_recvmsg()
  ...
2019-12-08 13:28:11 -08:00
Stefano Garzarella
8a3cc29c31 vhost/vsock: accept only packets with the right dst_cid
When we receive a new packet from the guest, we check if the
src_cid is correct, but we forgot to check the dst_cid.

The host should accept only packets where dst_cid is
equal to the host CID.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-07 11:59:51 -08:00
Andrey Konovalov
8f6a7f96dc vhost, kcov: collect coverage from vhost_worker
Add kcov_remote_start()/kcov_remote_stop() annotations to the
vhost_worker() function, which is responsible for processing vhost
works.

Since vhost_worker() threads are spawned per vhost device instance the
common kcov handle is used for kcov_remote_start()/stop() annotations
(see Documentation/dev-tools/kcov.rst for details).  As the result kcov
can now be used to collect coverage from vhost worker threads.

Link: http://lkml.kernel.org/r/e49d5d154e5da6c9ada521d2b7ce10a49ce9f98b.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexander Potapenko <glider@google.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Marco Elver <elver@google.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-04 19:44:14 -08:00
Linus Torvalds
0da522107e compat_ioctl: remove most of fs/compat_ioctl.c
As part of the cleanup of some remaining y2038 issues, I came to
 fs/compat_ioctl.c, which still has a couple of commands that need support
 for time64_t.
 
 In completely unrelated work, I spent time on cleaning up parts of this
 file in the past, moving things out into drivers instead.
 
 After Al Viro reviewed an earlier version of this series and did a lot
 more of that cleanup, I decided to try to completely eliminate the rest
 of it and move it all into drivers.
 
 This series incorporates some of Al's work and many patches of my own,
 but in the end stops short of actually removing the last part, which is
 the scsi ioctl handlers. I have patches for those as well, but they need
 more testing or possibly a rewrite.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground

Pull removal of most of fs/compat_ioctl.c from Arnd Bergmann:
 "As part of the cleanup of some remaining y2038 issues, I came to
  fs/compat_ioctl.c, which still has a couple of commands that need
  support for time64_t.

  In completely unrelated work, I spent time on cleaning up parts of
  this file in the past, moving things out into drivers instead.

  After Al Viro reviewed an earlier version of this series and did a lot
  more of that cleanup, I decided to try to completely eliminate the
  rest of it and move it all into drivers.

  This series incorporates some of Al's work and many patches of my own,
  but in the end stops short of actually removing the last part, which
  is the scsi ioctl handlers. I have patches for those as well, but they
  need more testing or possibly a rewrite"

* tag 'compat-ioctl-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (42 commits)
  scsi: sd: enable compat ioctls for sed-opal
  pktcdvd: add compat_ioctl handler
  compat_ioctl: move SG_GET_REQUEST_TABLE handling
  compat_ioctl: ppp: move simple commands into ppp_generic.c
  compat_ioctl: handle PPPIOCGIDLE for 64-bit time_t
  compat_ioctl: move PPPIOCSCOMPRESS to ppp_generic
  compat_ioctl: unify copy-in of ppp filters
  tty: handle compat PPP ioctls
  compat_ioctl: move SIOCOUTQ out of compat_ioctl.c
  compat_ioctl: handle SIOCOUTQNSD
  af_unix: add compat_ioctl support
  compat_ioctl: reimplement SG_IO handling
  compat_ioctl: move WDIOC handling into wdt drivers
  fs: compat_ioctl: move FITRIM emulation into file systems
  gfs2: add compat_ioctl support
  compat_ioctl: remove unused convert_in_user macro
  compat_ioctl: remove last RAID handling code
  compat_ioctl: remove /dev/raw ioctl translation
  compat_ioctl: remove PCI ioctl translation
  compat_ioctl: remove joystick ioctl translation
  ...
2019-12-01 13:46:15 -08:00
Stefano Garzarella
ed8640a961 vhost/vsock: refuse CID assigned to the guest->host transport
In a nested VM environment, we have to refuse to assign to a nested
guest the same CID assigned to our guest->host transport.
In this way, the user can use the local CID for loopback.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:12:18 -08:00
Stefano Garzarella
6a2c096210 vsock: prevent transport modules unloading
This patch adds 'module' member in the 'struct vsock_transport'
in order to get/put the transport module. This prevents the
module unloading while sockets are assigned to it.

We increase the module refcnt when a socket is assigned to a
transport, and we decrease the module refcnt when the socket
is destructed.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:12:18 -08:00
Stefano Garzarella
c0cfa2d8a7 vsock: add multi-transports support
This patch adds the support of multiple transports in the
VSOCK core.

With the multi-transports support, we can use vsock with nested VMs
(using also different hypervisors) loading both guest->host and
host->guest transports at the same time.

Major changes:
- vsock core module can be loaded regardless of the transports
- vsock_core_init() and vsock_core_exit() are renamed to
  vsock_core_register() and vsock_core_unregister()
- vsock_core_register() has a feature parameter (H2G, G2H, DGRAM)
  to identify which directions the transport can handle and if it's
  support DGRAM (only vmci)
- each stream socket is assigned to a transport when the remote CID
  is set (during the connect() or when we receive a connection request
  on a listener socket).
  The remote CID is used to decide which transport to use:
  - remote CID <= VMADDR_CID_HOST will use guest->host transport;
  - remote CID == local_cid (guest->host transport) will use guest->host
    transport for loopback (host->guest transports don't support loopback);
  - remote CID > VMADDR_CID_HOST will use host->guest transport;
- listener sockets are not bound to any transports since no transport
  operations are done on it. In this way we can create a listener
  socket, also if the transports are not loaded or with VMADDR_CID_ANY
  to listen on all transports.
- DGRAM sockets are handled as before, since only the vmci_transport
  provides this feature.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:12:18 -08:00
Stefano Garzarella
b9f2b0ffde vsock: handle buffer_size sockopts in the core
virtio_transport and vmci_transport handle the buffer_size
sockopts in a very similar way.

In order to support multiple transports, this patch moves this
handling in the core to allow the user to change the options
also if the socket is not yet assigned to any transport.

This patch also adds the '.notify_buffer_size' callback in the
'struct virtio_transport' in order to inform the transport,
when the buffer_size is changed by the user. It is also useful
to limit the 'buffer_size' requested (e.g. virtio transports).

Acked-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:12:18 -08:00
Stefano Garzarella
4c7246dc45 vsock/virtio: add transport parameter to the virtio_transport_reset_no_sock()
We are going to add 'struct vsock_sock *' parameter to
virtio_transport_get_ops().

In some cases, like in the virtio_transport_reset_no_sock(),
we don't have any socket assigned to the packet received,
so we can't use the virtio_transport_get_ops().

In order to allow virtio_transport_reset_no_sock() to use the
'.send_pkt' callback from the 'vhost_transport' or 'virtio_transport',
we add the 'struct virtio_transport *' to it and to its caller:
virtio_transport_recv_pkt().

We moved the 'vhost_transport' and 'virtio_transport' definition,
to pass their address to the virtio_transport_recv_pkt().

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-14 18:12:18 -08:00
Jason Wang
b3683dee84 vringh: fix copy direction of vringh_iov_push_kern()
We want to copy from iov to buf, so the direction was wrong.

Note: no real user for the helper, but it will be used by future
features.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-28 04:25:04 -04:00
Arnd Bergmann
407e9ef724 compat_ioctl: move drivers to compat_ptr_ioctl
Each of these drivers has a copy of the same trivial helper function to
convert the pointer argument and then call the native ioctl handler.

We now have a generic implementation of that, so use it.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-10-23 17:23:43 +02:00
Michael S. Tsirkin
245cdd9fbd vhost/test: stop device before reset
When device stop was moved out of reset, test device wasn't updated to
stop before reset, this resulted in a use after free.  Fix by invoking
stop appropriately.

Fixes: b211616d71 ("vhost: move -net specific code out")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-13 09:38:27 -04:00
David S. Miller
aa2eaa8c27 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Minor overlapping changes in the btusb and ixgbe drivers.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-15 14:17:27 +02:00
Michael S. Tsirkin
0d4a3f2abb Revert "vhost: block speculation of translated descriptors"
This reverts commit a89db445fb.

I was hasty to include this patch, and it breaks the build on 32 bit.
Defence in depth is good but let's do it properly.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-09-14 15:21:51 -04:00
yongduan
060423bfde vhost: make sure log_num < in_num
The code assumes log_num < in_num everywhere, and that is true as long as
in_num is incremented by descriptor iov count, and log_num by 1. However
this breaks if there's a zero sized descriptor.

As a result, if a malicious guest creates a vring desc with desc.len = 0,
it may cause the host kernel to crash by overflowing the log array. This
bug can be triggered during the VM migration.

There's no need to log when desc.len = 0, so just don't increment log_num
in this case.

Fixes: 3a4d5c94e9 ("vhost_net: a kernel-level virtio server")
Cc: stable@vger.kernel.org
Reviewed-by: Lidong Chen <lidongchen@tencent.com>
Signed-off-by: ruippan <ruippan@tencent.com>
Signed-off-by: yongduan <yongduan@tencent.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-09-11 15:15:26 -04:00
Michael S. Tsirkin
a89db445fb vhost: block speculation of translated descriptors
iovec addresses coming from vhost are assumed to be
pre-validated, but in fact can be speculated to a value
out of range.

Userspace address are later validated with array_index_nospec so we can
be sure kernel info does not leak through these addresses, but vhost
must also not leak userspace info outside the allowed memory table to
guests.

Following the defence in depth principle, make sure
the address is not validated out of node range.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@vger.kernel.org
Acked-by: Jason Wang <jasowang@redhat.com>
Tested-by: Jason Wang <jasowang@redhat.com>
2019-09-11 15:15:07 -04:00
Michael S. Tsirkin
3d2c7d3704 Revert "vhost: access vq metadata through kernel virtual address"
This reverts commit 7f466032dc ("vhost: access vq metadata through
kernel virtual address").  The commit caused a bunch of issues, and
while commit 73f628ec9e ("vhost: disable metadata prefetch
optimization") disabled the optimization it's not nice to keep lots of
dead code around.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-09-04 07:39:48 -04:00
Yunsheng Lin
896fc242bc vhost: Remove unnecessary variable
It is unnecessary to use ret variable to return the error
code, just return the error code directly.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-09-04 06:21:17 -04:00
Tiwei Bie
264b563b86 vhost/test: fix build for vhost test
Since vhost_exceeds_weight() was introduced, callers need to specify
the packet weight and byte weight in vhost_dev_init(). Note that, the
packet weight isn't counted in this patch to keep the original behavior
unchanged.

Fixes: e82b9b0727 ("vhost: introduce vhost_exceeds_weight()")
Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2019-09-04 06:21:17 -04:00
Tiwei Bie
93d2c4de8d vhost/test: fix build for vhost test
Since below commit, callers need to specify the iov_limit in
vhost_dev_init() explicitly.

Fixes: b46a0bf78a ("vhost: fix OOB in get_rx_bufs()")
Cc: stable@vger.kernel.org
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
2019-09-04 06:21:17 -04:00
David S. Miller
13dfb3fa49 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Just minor overlapping changes in the conflicts here.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-06 18:44:57 -07:00
Stefano Garzarella
6dbd3e66e7 vhost/vsock: split packets to send using multiple buffers
If the packets to sent to the guest are bigger than the buffer
available, we can split them, using multiple buffers and fixing
the length in the packet header.
This is safe since virtio-vsock supports only stream sockets.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-30 15:00:00 -07:00
Stefano Garzarella
473c7391ce vsock/virtio: limit the memory used per-socket
Since virtio-vsock was introduced, the buffers filled by the host
and pushed to the guest using the vring, are directly queued in
a per-socket list. These buffers are preallocated by the guest
with a fixed size (4 KB).

The maximum amount of memory used by each socket should be
controlled by the credit mechanism.
The default credit available per-socket is 256 KB, but if we use
only 1 byte per packet, the guest can queue up to 262144 of 4 KB
buffers, using up to 1 GB of memory per-socket. In addition, the
guest will continue to fill the vring with new 4 KB free buffers
to avoid starvation of other sockets.

This patch mitigates this issue copying the payload of small
packets (< 128 bytes) into the buffer of last packet queued, in
order to avoid wasting memory.

Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-30 15:00:00 -07:00
Michael S. Tsirkin
73f628ec9e vhost: disable metadata prefetch optimization
This seems to cause guest and host memory corruption.
Disable for now until we get a better handle on that.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-26 07:49:29 -04:00
Linus Torvalds
3a1d5384b7 virtio, vhost: fixes, features, performance
new iommu device
 vhost guest memory access using vmap (just meta-data for now)
 minor fixes
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
 
 Note: due to code driver changes the driver-core tree, the following
 patch is needed when merging tree with commit 92ce7e83b4
 ("driver_find_device: Unify the match function with
 class_find_device()") in the driver-core tree:
 
 From: Nathan Chancellor <natechancellor@gmail.com>
 Subject: [PATCH] iommu/virtio: Constify data parameter in viommu_match_node
 
 After commit 92ce7e83b4 ("driver_find_device: Unify the match
 function with class_find_device()") in the driver-core tree.
 
 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
 
 ---
  drivers/iommu/virtio-iommu.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)
 
 diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c
 index 4620dd221ffd..433f4d2ee956 100644
 --- a/drivers/iommu/virtio-iommu.c
 +++ b/drivers/iommu/virtio-iommu.c
 @@ -839,7 +839,7 @@ static void viommu_put_resv_regions(struct device *dev, struct list_head *head)
  static struct iommu_ops viommu_ops;
  static struct virtio_driver virtio_iommu_drv;
 
 -static int viommu_match_node(struct device *dev, void *data)
 +static int viommu_match_node(struct device *dev, const void *data)
  {
  	return dev->parent->fwnode == data;
  }
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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, features, performance:

   - new iommu device

   - vhost guest memory access using vmap (just meta-data for now)

   - minor fixes"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio-mmio: add error check for platform_get_irq
  scsi: virtio_scsi: Use struct_size() helper
  iommu/virtio: Add event queue
  iommu/virtio: Add probe request
  iommu: Add virtio-iommu driver
  PCI: OF: Initialize dev->fwnode appropriately
  of: Allow the iommu-map property to omit untranslated devices
  dt-bindings: virtio: Add virtio-pci-iommu node
  dt-bindings: virtio-mmio: Add IOMMU description
  vhost: fix clang build warning
  vhost: access vq metadata through kernel virtual address
  vhost: factor out setting vring addr and num
  vhost: introduce helpers to get the size of metadata area
  vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
  vhost: fine grain userspace memory accessors
  vhost: generalize adding used elem
2019-07-17 11:26:09 -07:00
Linus Torvalds
237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds
e9a83bd232 It's been a relatively busy cycle for docs:
- A fair pile of RST conversions, many from Mauro.  These create more
    than the usual number of simple but annoying merge conflicts with other
    trees, unfortunately.  He has a lot more of these waiting on the wings
    that, I think, will go to you directly later on.
 
  - A new document on how to use merges and rebases in kernel repos, and one
    on Spectre vulnerabilities.
 
  - Various improvements to the build system, including automatic markup of
    function() references because some people, for reasons I will never
    understand, were of the opinion that :c:func:``function()`` is
    unattractive and not fun to type.
 
  - We now recommend using sphinx 1.7, but still support back to 1.4.
 
  - Lots of smaller improvements, warning fixes, typo fixes, etc.
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Merge tag 'docs-5.3' of git://git.lwn.net/linux

Pull Documentation updates from Jonathan Corbet:
 "It's been a relatively busy cycle for docs:

   - A fair pile of RST conversions, many from Mauro. These create more
     than the usual number of simple but annoying merge conflicts with
     other trees, unfortunately. He has a lot more of these waiting on
     the wings that, I think, will go to you directly later on.

   - A new document on how to use merges and rebases in kernel repos,
     and one on Spectre vulnerabilities.

   - Various improvements to the build system, including automatic
     markup of function() references because some people, for reasons I
     will never understand, were of the opinion that
     :c:func:``function()`` is unattractive and not fun to type.

   - We now recommend using sphinx 1.7, but still support back to 1.4.

   - Lots of smaller improvements, warning fixes, typo fixes, etc"

* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
  docs: automarkup.py: ignore exceptions when seeking for xrefs
  docs: Move binderfs to admin-guide
  Disable Sphinx SmartyPants in HTML output
  doc: RCU callback locks need only _bh, not necessarily _irq
  docs: format kernel-parameters -- as code
  Doc : doc-guide : Fix a typo
  platform: x86: get rid of a non-existent document
  Add the RCU docs to the core-api manual
  Documentation: RCU: Add TOC tree hooks
  Documentation: RCU: Rename txt files to rst
  Documentation: RCU: Convert RCU UP systems to reST
  Documentation: RCU: Convert RCU linked list to reST
  Documentation: RCU: Convert RCU basic concepts to reST
  docs: filesystems: Remove uneeded .rst extension on toctables
  scripts/sphinx-pre-install: fix out-of-tree build
  docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
  Documentation: PGP: update for newer HW devices
  Documentation: Add section about CPU vulnerabilities for Spectre
  Documentation: platform: Delete x86-laptop-drivers.txt
  docs: Note that :c:func: should no longer be used
  ...
2019-07-09 12:34:26 -07:00
David S. Miller
92ad6325cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor SPDX change conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 08:59:24 -04:00
Thomas Gleixner
7a338472f2 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 482
Based on 1 normalized pattern(s):

  this work is licensed under the terms of the gnu gpl version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 48 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081204.624030236@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:52 +02:00
Jason Wang
098eadce3c vhost_net: disable zerocopy by default
Vhost_net was known to suffer from HOL[1] issues which is not easy to
fix. Several downstream disable the feature by default. What's more,
the datapath was split and datacopy path got the support of batching
and XDP support recently which makes it faster than zerocopy part for
small packets transmission.

It looks to me that disable zerocopy by default is more
appropriate. It cold be enabled by default again in the future if we
fix the above issues.

[1] https://patchwork.kernel.org/patch/3787671/

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-17 13:58:02 -07:00
Jonathan Corbet
8afecfb0ec Linux 5.2-rc4
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Merge tag 'v5.2-rc4' into mauro

We need to pick up post-rc1 changes to various document files so they don't
get lost in Mauro's massive RST conversion push.
2019-06-14 14:18:53 -06:00
Mauro Carvalho Chehab
cb1aaebea8 docs: fix broken documentation links
Mostly due to x86 and acpi conversion, several documentation
links are still pointing to the old file. Fix them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-08 13:42:13 -06:00
Michael S. Tsirkin
0b4a7092ff vhost: fix clang build warning
Clang warns:

  drivers/vhost/vhost.c:2085:5: warning: macro expansion producing
  'defined' has undefined behavior [-Wexpansion-to-defined]
  #if VHOST_ARCH_CAN_ACCEL_UACCESS
      ^
  drivers/vhost/vhost.h:98:38: note: expanded from macro
  'VHOST_ARCH_CAN_ACCEL_UACCESS'
  #define VHOST_ARCH_CAN_ACCEL_UACCESS defined(CONFIG_MMU_NOTIFIER) && \
                                       ^

It's being pedantic for the sake of portability, but the fix is easy
enough.

Rework the definition of VHOST_ARCH_CAN_ACCEL_UACCESS to expand to a constant.

Fixes: 7f466032dc ("vhost: access vq metadata through kernel virtual address")
Link: https://github.com/ClangBuiltLinux/linux/issues/508
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
2019-06-06 17:32:13 -04:00
Jason Wang
7f466032dc vhost: access vq metadata through kernel virtual address
It was noticed that the copy_to/from_user() friends that was used to
access virtqueue metdata tends to be very expensive for dataplane
implementation like vhost since it involves lots of software checks,
speculation barriers, hardware feature toggling (e.g SMAP). The
extra cost will be more obvious when transferring small packets since
the time spent on metadata accessing become more significant.

This patch tries to eliminate those overheads by accessing them
through direct mapping of those pages. Invalidation callbacks is
implemented for co-operation with general VM management (swap, KSM,
THP or NUMA balancing). We will try to get the direct mapping of vq
metadata before each round of packet processing if it doesn't
exist. If we fail, we will simplely fallback to copy_to/from_user()
friends.

This invalidation and direct mapping access are synchronized through
spinlock and RCU. All matedata accessing through direct map is
protected by RCU, and the setup or invalidation are done under
spinlock.

This method might does not work for high mem page which requires
temporary mapping so we just fallback to normal
copy_to/from_user() and may not for arch that has virtual tagged cache
since extra cache flushing is needed to eliminate the alias. This will
result complex logic and bad performance. For those archs, this patch
simply go for copy_to/from_user() friends. This is done by ruling out
kernel mapping codes through ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE.

Note that this is only done when device IOTLB is not enabled. We
could use similar method to optimize IOTLB in the future.

Tests shows at most about 23% improvement on TX PPS when using
virtio-user + vhost_net + xdp1 + TAP on 2.6GHz Broadwell:

        SMAP on | SMAP off
Before: 5.2Mpps | 7.1Mpps
After:  6.4Mpps | 8.2Mpps

Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-parisc@vger.kernel.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05 21:09:18 -04:00
Jason Wang
feebcaeac7 vhost: factor out setting vring addr and num
Factoring vring address and num setting which needs special care for
accelerating vq metadata accessing.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05 16:23:53 -04:00
Jason Wang
4942e8254d vhost: introduce helpers to get the size of metadata area
To avoid code duplication since it will be used by kernel VA prefetching.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05 16:23:53 -04:00
Jason Wang
9b5e830b71 vhost: rename vq_iotlb_prefetch() to vq_meta_prefetch()
Rename the function to be more accurate since it actually tries to
prefetch vq metadata address in IOTLB. And this will be used by
following patch to prefetch metadata virtual addresses.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05 16:23:52 -04:00
Jason Wang
7b5d753ebc vhost: fine grain userspace memory accessors
This is used to hide the metadata address from virtqueue helpers. This
will allow to implement a vmap based fast accessing to metadata.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-05 16:23:52 -04:00