Re: [PATCH net-next v9 2/4] virtio/vsock: send credit update during setting SO_RCVLOWAT

[Stefano Garzarella]

On Thu, Dec 14, 2023 at 12:19:45PM +0300, Arseniy Krasnov wrote:
> Send credit update message when SO_RCVLOWAT is updated and it is bigger
> than number of bytes in rx queue. It is needed, because 'poll()' will
> wait until number of bytes in rx queue will be not smaller than
> SO_RCVLOWAT, so kick sender to send more data. Otherwise mutual hungup
> for tx/rx is possible: sender waits for free space and receiver is
> waiting data in 'poll()'.
>
> Fixes: b89d882dc9fc ("vsock/virtio: reduce credit update messages")
> Signed-off-by: Arseniy Krasnov <avkrasnov@xxxxxxxxxxxxxxxxx>
> Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
> Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx>
> ---
> Changelog:
> v1 -> v2:
>  * Update commit message by removing 'This patch adds XXX' manner.
>  * Do not initialize 'send_update' variable - set it directly during
>    first usage.
> v3 -> v4:
>  * Fit comment in 'virtio_transport_notify_set_rcvlowat()' to 80 chars.
> v4 -> v5:
>  * Do not change callbacks order in transport structures.
> v5 -> v6:
>  * Reorder callbacks in transport structures.
>  * Do to send credit update when 'fwd_cnt' == 'last_fwd_cnt'.
> v8 -> v9:
>  * Add 'Fixes' tag.
>
> drivers/vhost/vsock.c                   |  1 +
> include/linux/virtio_vsock.h            |  1 +
> net/vmw_vsock/virtio_transport.c        |  1 +
> net/vmw_vsock/virtio_transport_common.c | 30 +++++++++++++++++++++++++
> net/vmw_vsock/vsock_loopback.c          |  1 +
> 5 files changed, 34 insertions(+)

As I already mentioned in the cover letter, this patch doesn't compile
unless we apply patch 3 before this one, so:

Nacked-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>