Re: [PATCH 4.19 018/264] chelsio/chtls: correct function return and return type

[Jakub Kicinski]

On Wed, 28 Oct 2020 07:58:04 +0100 Pavel Machek wrote:
> > From: Vinay Kumar Yadav <vinay.yadav@xxxxxxxxxxx>
> > 
> > [ Upstream commit 8580a61aede28d441e1c80588803411ee86aa299 ]
> > 
> > csk_mem_free() should return true if send buffer is available,
> > false otherwise.  
> 
> > Fixes: 3b8305f5c844 ("crypto: chtls - wait for memory sendmsg, sendpage")  
> 
> This does not fix anything. In fact, binary code should be exactly
> equivalent. It does not need to be in 4.19-stable.

Not sure why you think binary code will be equivalent.

The condition changed from:

cdev->max_host_sndbuf != sk->sk_wmem_queued

to

cdev->max_host_sndbuf > sk->sk_wmem_queued


That said Chelsio would have to comment if it really fixes any real
user-visible issue :)

> > @@ -914,9 +914,9 @@ static int tls_header_read(struct tls_hd
> >  	return (__force int)cpu_to_be16(thdr->length);
> >  }
> >  
> > -static int csk_mem_free(struct chtls_dev *cdev, struct sock *sk)
> > +static bool csk_mem_free(struct chtls_dev *cdev, struct sock *sk)
> >  {
> > -	return (cdev->max_host_sndbuf - sk->sk_wmem_queued);
> > +	return (cdev->max_host_sndbuf - sk->sk_wmem_queued > 0);
> >  }
> >  
> >  static int csk_wait_memory(struct chtls_dev *cdev,