linux.git/drivers/vhost/vsock.c, branch v5.19

vhost: rename vhost_work_dev_flush

2022-05-31T16:45:10+00:00

This patch renames vhost_work_dev_flush to just vhost_dev_flush to
relfect that it flushes everything on the device and that drivers
don't know/care that polls are based on vhost_works. Drivers just
flush the entire device and polls, and works for vhost-scsi
management TMFs and IO net virtqueues, etc all are flushed.

Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Reviewed-by: Stefano Garzarella 
Message-Id: <20220517180850.198915-9-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

vhost_vsock: simplify vhost_vsock_flush()

2022-05-31T16:45:10+00:00

vhost_vsock_flush() calls vhost_work_dev_flush(vsock->vqs[i].poll.dev)
before vhost_work_dev_flush(&vsock->dev). This seems pointless
as vsock->vqs[i].poll.dev is the same as &vsock->dev and several flushes
in a row doesn't do anything useful, one is just enough.

Signed-off-by: Andrey Ryabinin 
Reviewed-by: Stefano Garzarella 
Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Message-Id: <20220517180850.198915-6-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

vhost: get rid of vhost_poll_flush() wrapper

2022-05-31T16:45:10+00:00

vhost_poll_flush() is a simple wrapper around vhost_work_dev_flush().
It gives wrong impression that we are doing some work over vhost_poll,
while in fact it flushes vhost_poll->dev.
It only complicate understanding of the code and leads to mistakes
like flushing the same vhost_dev several times in a row.

Just remove vhost_poll_flush() and call vhost_work_dev_flush() directly.

Signed-off-by: Andrey Ryabinin 
[merge vhost_poll_flush removal from Stefano Garzarella]
Signed-off-by: Mike Christie 
Reviewed-by: Chaitanya Kulkarni 
Acked-by: Jason Wang 
Reviewed-by: Stefano Garzarella 
Message-Id: <20220517180850.198915-2-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

vsock: each transport cycles only on its own sockets

2022-03-12T07:14:19+00:00

When iterating over sockets using vsock_for_each_connected_socket, make
sure that a transport filters out sockets that don't belong to the
transport.

There actually was an issue caused by this; in a nested VM
configuration, destroying the nested VM (which often involves the
closing of /dev/vhost-vsock if there was h2g connections to the nested
VM) kills not only the h2g connections, but also all existing g2h
connections to the (outmost) host which are totally unrelated.

Tested: Executed the following steps on Cuttlefish (Android running on a
VM) [1]: (1) Enter into an `adb shell` session - to have a g2h
connection inside the VM, (2) open and then close /dev/vhost-vsock by
`exec 3< /dev/vhost-vsock && exec 3<&-`, (3) observe that the adb
session is not reset.

[1] https://android.googlesource.com/device/google/cuttlefish/

Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
Reviewed-by: Stefano Garzarella 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Jiyong Park 
Link: https://lore.kernel.org/r/20220311020017.1509316-1-jiyong@google.com
Signed-off-by: Jakub Kicinski

vhost/vsock: don't check owner in vhost_vsock_stop() while releasing

2022-02-23T12:32:33+00:00

vhost_vsock_stop() calls vhost_dev_check_owner() to check the device
ownership. It expects current->mm to be valid.

vhost_vsock_stop() is also called by vhost_vsock_dev_release() when
the user has not done close(), so when we are in do_exit(). In this
case current->mm is invalid and we're releasing the device, so we
should clean it anyway.

Let's check the owner only when vhost_vsock_stop() is called
by an ioctl.

When invoked from release we can not fail so we don't check return
code of vhost_vsock_stop(). We need to stop vsock even if it's not
the owner.

Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko")
Cc: stable@vger.kernel.org
Reported-by: syzbot+1e3ea63db39f2b4440e0@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+3140b17cb44a7b174008@syzkaller.appspotmail.com
Signed-off-by: Stefano Garzarella 
Acked-by: Jason Wang 
Signed-off-by: David S. Miller

vhost/vsock: cleanup removing `len` variable

2021-11-25T00:00:28+00:00

We can increment `total_len` directly and remove `len` since it
is no longer used for vhost_add_used().

Signed-off-by: Stefano Garzarella 
Link: https://lore.kernel.org/r/20211122163525.294024-3-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefan Hajnoczi

vhost/vsock: fix incorrect used length reported to the guest

2021-11-25T00:00:28+00:00

The "used length" reported by calling vhost_add_used() must be the
number of bytes written by the device (using "in" buffers).

In vhost_vsock_handle_tx_kick() the device only reads the guest
buffers (they are all "out" buffers), without writing anything,
so we must pass 0 as "used length" to comply virtio spec.

Fixes: 433fc58e6bf2 ("VSOCK: Introduce vhost_vsock.ko")
Cc: stable@vger.kernel.org
Reported-by: Halil Pasic 
Suggested-by: Jason Wang 
Signed-off-by: Stefano Garzarella 
Link: https://lore.kernel.org/r/20211122163525.294024-2-sgarzare@redhat.com
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefan Hajnoczi 
Reviewed-by: Halil Pasic

vhost/vsock: support MSG_EOR bit processing

2021-09-05T20:23:09+00:00

'MSG_EOR' handling has similar logic as 'MSG_EOM' - if bit present
in packet's header, reset it to 0. Then restore it back if packet
processing wasn't completed. Instead of bool variable for each
flag, bit mask variable was added: it has logical OR of 'MSG_EOR'
and 'MSG_EOM' if needed, to restore flags, this variable is ORed
with flags field of packet.

Signed-off-by: Arseny Krasnov 
Link: https://lore.kernel.org/r/20210903123238.3273526-1-arseny.krasnov@kaspersky.com
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefano Garzarella

virtio/vsock: rename 'EOR' to 'EOM' bit.

2021-09-05T20:23:08+00:00

This current implemented bit is used to mark end of messages
('EOM' - end of message), not records('EOR' - end of record).
Also rename 'record' to 'message' in implementation as it is
different things.

Signed-off-by: Arseny Krasnov 
Reviewed-by: Stefano Garzarella 
Link: https://lore.kernel.org/r/20210903123109.3273053-1-arseny.krasnov@kaspersky.com
Signed-off-by: Michael S. Tsirkin

vhost: remove work arg from vhost_work_flush

2021-07-03T08:50:54+00:00

vhost_work_flush doesn't do anything with the work arg. This patch drops
it and then renames vhost_work_flush to vhost_work_dev_flush to reflect
that the function flushes all the works in the dev and not just a
specific queue or work item.

Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20210525174733.6212-2-michael.christie@oracle.com
Reviewed-by: Stefano Garzarella 
Signed-off-by: Michael S. Tsirkin