Re: [PATCH net-next v2 1/4] vm_sockets: Include flags field in the vsock address data structure

[Stefano Garzarella]

On Fri, Dec 04, 2020 at 07:02:32PM +0200, Andra Paraschiv wrote:
> vsock enables communication between virtual machines and the host they
> are running on. With the multi transport support (guest->host and
> host->guest), nested VMs can also use vsock channels for communication.
>
> In addition to this, by default, all the vsock packets are forwarded to
> the host, if no host->guest transport is loaded. This behavior can be
> implicitly used for enabling vsock communication between sibling VMs.
>
> Add a flags field in the vsock address data structure that can be used
> to explicitly mark the vsock connection as being targeted for a certain
> type of communication. This way, can distinguish between different use
> cases such as nested VMs and sibling VMs.
>
> Use the already available "svm_reserved1" field and mark it as a flags
> field instead. This field can be set when initializing the vsock address
> variable used for the connect() call.
>
> Changelog
>
> v1 -> v2
>
> * Update the field name to "svm_flags".
> * Split the current patch in 2 patches.

Usually the changelog goes after the 3 dashes, but I'm not sure there is 
a strict rule :-)

Anyway the patch LGTM:

Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>

> Signed-off-by: Andra Paraschiv <andraprs@xxxxxxxxxx>
> ---
> include/uapi/linux/vm_sockets.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/uapi/linux/vm_sockets.h b/include/uapi/linux/vm_sockets.h
> index fd0ed7221645d..46735376a57a8 100644
> --- a/include/uapi/linux/vm_sockets.h
> +++ b/include/uapi/linux/vm_sockets.h
> @@ -145,7 +145,7 @@
>
> struct sockaddr_vm {
> 	__kernel_sa_family_t svm_family;
> -	unsigned short svm_reserved1;
> +	unsigned short svm_flags;
> 	unsigned int svm_port;
> 	unsigned int svm_cid;
> 	unsigned char svm_zero[sizeof(struct sockaddr) -
> --
> 2.20.1 (Apple Git-117)
>
>
>
>
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