Re: [RFC PATCH v3 04/17] vsock/virtio: non-linear skb handling for tap

[Arseniy Krasnov]

On 22.05.2023 16:13, Simon Horman wrote:
> On Mon, May 22, 2023 at 10:39:37AM +0300, Arseniy Krasnov wrote:
>> For tap device new skb is created and data from the current skb is
>> copied to it. This adds copying data from non-linear skb to new
>> the skb.
>>
>> Signed-off-by: Arseniy Krasnov <AVKrasnov@xxxxxxxxxxxxxx>
>> ---
>>  net/vmw_vsock/virtio_transport_common.c | 31 ++++++++++++++++++++++---
>>  1 file changed, 28 insertions(+), 3 deletions(-)
>>
>> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
>> index 16effa8d55d2..9854f48a0544 100644
>> --- a/net/vmw_vsock/virtio_transport_common.c
>> +++ b/net/vmw_vsock/virtio_transport_common.c
>> @@ -106,6 +106,27 @@ virtio_transport_alloc_skb(struct virtio_vsock_pkt_info *info,
>>  	return NULL;
>>  }
>>  
>> +static void virtio_transport_copy_nonlinear_skb(struct sk_buff *skb,
>> +						void *dst,
>> +						size_t len)
>> +{
>> +	struct iov_iter iov_iter = { 0 };
>> +	struct iovec iovec;
>> +	size_t to_copy;
>> +
>> +	iovec.iov_base = dst;
> 
> Hi Arseniy,
> 
> Sparse seems unhappy about this.
> Though, TBH, I'm unsure what should be done about it.
> 
> .../virtio_transport_common.c:117:24: warning: incorrect type in assignment (different address spaces)
> .../virtio_transport_common.c:117:24:    expected void [noderef] __user *iov_base
> .../virtio_transport_common.c:117:24:    got void *dst
> 
Got it, i'll check how to resolve this problem!

Thanks!
> 
> ...