similar to: DMA from stack in virtio_net and virtio_console

Programming vids (adding or removing them) still passes guest-endian values in the DMA buffer. That's wrong if guest is big-endian and when virtio 1 is enabled. Note: this is on top of a previous patch: virtio_net: split out ctrl buffer Fixes: 9465a7a6f ("virtio_net: enable v1.0 support") Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 6

Programming vids (adding or removing them) still passes guest-endian values in the DMA buffer. That's wrong if guest is big-endian and when virtio 1 is enabled. Note: this is on top of a previous patch: virtio_net: split out ctrl buffer Fixes: 9465a7a6f ("virtio_net: enable v1.0 support") Signed-off-by: Michael S. Tsirkin <mst at redhat.com> --- drivers/net/virtio_net.c | 6

When sending control commands, virtio net sets up several buffers for DMA. The buffers are all part of the net device which means it's actually allocated by kvmalloc so it's in theory (on extreme memory pressure) possible to get a vmalloc'ed buffer which on some platforms means we can't DMA there. Fix up by moving the DMA buffers into a separate structure. Reported-by: Mikulas

virtio_console uses a small DMA buffer for control requests. Move that buffer into heap memory. Doing virtio DMA on the stack is normally okay on non-DMA-API virtio systems (which is currently most of them), but it breaks completely if the stack is virtually mapped. Tested by typing both directions using picocom aimed at /dev/hvc0. Signed-off-by: Andy Lutomirski <luto at kernel.org> ---

virtio_console uses a small DMA buffer for control requests. Move that buffer into heap memory. Doing virtio DMA on the stack is normally okay on non-DMA-API virtio systems (which is currently most of them), but it breaks completely if the stack is virtually mapped. Tested by typing both directions using picocom aimed at /dev/hvc0. Signed-off-by: Andy Lutomirski <luto at kernel.org> ---

When sending control commands, virtio net sets up several buffers for DMA. The buffers are all part of the net device which means it's actually allocated by kvmalloc so in theory (on extreme memory pressure) it's possible to get a vmalloc'ed buffer which on some platforms means we can't DMA there. Fix up by moving the DMA buffers out into a separate structure. Reported-by:

Rather than handing a scatterlist[] and out and in numbers to virtqueue_add_buf(), hand two separate ones which can be chained. I shall refrain from ranting about what a disgusting hack chained scatterlists are. I'll just note that this doesn't make things simpler (see diff). The scatterlists we use can be too large for the stack, so we put them in our device struct and reuse them. But

Rather than handing a scatterlist[] and out and in numbers to virtqueue_add_buf(), hand two separate ones which can be chained. I shall refrain from ranting about what a disgusting hack chained scatterlists are. I'll just note that this doesn't make things simpler (see diff). The scatterlists we use can be too large for the stack, so we put them in our device struct and reuse them. But

The virtio_net driver never sends the multicast address list to the host. This is because send command takes a pointer to scatter list to send but only inserts that one entry into the outgoing scatter list. This bug has been there since: commit f565a7c259d71cc186753653d978c646d2354b36 Author: Alex Williamson <alex.williamson at hp.com> Date: Wed Feb 4 09:02:45 2009 +0000 virtio_net:

The virtio_net driver never sends the multicast address list to the host. This is because send command takes a pointer to scatter list to send but only inserts that one entry into the outgoing scatter list. This bug has been there since: commit f565a7c259d71cc186753653d978c646d2354b36 Author: Alex Williamson <alex.williamson at hp.com> Date: Wed Feb 4 09:02:45 2009 +0000 virtio_net:

All the code passes NULL for the last sg list (in). Simplify by just removing it. Signed-off-by: Stephen Hemminger <stephen at networkplumber.org> --- a/drivers/net/virtio_net.c 2013-12-09 16:12:36.353164803 -0800 +++ b/drivers/net/virtio_net.c 2013-12-09 16:12:41.409051865 -0800 @@ -876,13 +876,12 @@ static netdev_tx_t start_xmit(struct sk_ * never fail unless improperly formated. */

The virtio block device holds a lock during I/O request processing. Kicking the virtqueue while the lock is held results in long lock hold times and increases contention for the lock. This patch modifies virtqueue_kick() to optionally release a lock while notifying the host. Virtio block is modified to pass in its lock. This allows other vcpus to queue I/O requests during the time spent

The virtio block device holds a lock during I/O request processing. Kicking the virtqueue while the lock is held results in long lock hold times and increases contention for the lock. This patch modifies virtqueue_kick() to optionally release a lock while notifying the host. Virtio block is modified to pass in its lock. This allows other vcpus to queue I/O requests during the time spent

virtio_net paravirtualized driver does not have a tx_timeout() function to guarantee that the driver will recover properly after receiving a timeout during a transmission of a packet. This patch add this feature and throw a timeout exception after 5 HZ. Considering some tests, this is the best time to use here. Signed-off-by: Julio Faracco <jcfaracco at gmail.com> Cc: Jason Wang

virtio_net paravirtualized driver does not have a tx_timeout() function to guarantee that the driver will recover properly after receiving a timeout during a transmission of a packet. This patch add this feature and throw a timeout exception after 5 HZ. Considering some tests, this is the best time to use here. Signed-off-by: Julio Faracco <jcfaracco at gmail.com> Cc: Jason Wang

Expose multiple char devices ("ports") for simple communication between the host userspace and guest. Sample offline usages can be: poking around in a guest to find out the file systems used, applications installed, etc. Online usages can be sharing of clipboard data between the guest and the host, sending information about logged-in users to the host, locking the screen or session when

Expose multiple char devices ("ports") for simple communication between the host userspace and guest. Sample offline usages can be: poking around in a guest to find out the file systems used, applications installed, etc. Online usages can be sharing of clipboard data between the guest and the host, sending information about logged-in users to the host, locking the screen or session when

Hello all, Here is a new iteration of the patch series that implements a transport for guest and host communications. I've tested for compatibility (old qemu & new kernel, new qemu & old kernel, new qemu & new kernel) and it all works fine. To maintain backward compatibility, the first port to be spawned (port at id 0) is to be a console port, to be bound to hvc. This keeps new

Hello all, Here is a new iteration of the patch series that implements a transport for guest and host communications. I've tested for compatibility (old qemu & new kernel, new qemu & old kernel, new qemu & new kernel) and it all works fine. To maintain backward compatibility, the first port to be spawned (port at id 0) is to be a console port, to be bound to hvc. This keeps new

On Wed, Oct 19, 2016 at 04:59:46PM +0300, Michael S. Tsirkin wrote: > On Tue, Oct 18, 2016 at 10:33:32PM -0400, Jarod Wilson wrote: > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > > index fad84f3..4885a42 100644 > > --- a/drivers/net/virtio_net.c > > +++ b/drivers/net/virtio_net.c > > @@ -1419,17 +1419,6 @@ static const struct ethtool_ops