Subject: Re: linux-next: manual merge of the net-next tree with the rdma tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 16 Aug 2018 09:41:22 +1000

Hi all,

On Mon, 2 Jul 2018 10:21:06 +1000 Stephen Rothwell <[email-masked]> wrote:
>
> Today's linux-next merge of the net-next tree got a conflict in:
> 
>   net/smc/smc_ib.c
> 
> between commit:
> 
>   ddb457c6993b ("net/smc: Replace ib_query_gid with rdma_get_gid_attr")
> 
> from the rdma tree and commit:
> 
>   be6a3f38ff2a ("net/smc: determine port attributes independent from pnet table")
> 
> from the net-next tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
> 
> -- 
> Cheers,
> Stephen Rothwell
> 
> diff --cc net/smc/smc_ib.c
> index 74f29f814ec1,36de2fd76170..000000000000
> --- a/net/smc/smc_ib.c
> +++ b/net/smc/smc_ib.c
> @@@ -144,6 -143,62 +144,66 @@@ out
>   	return rc;
>   }
>   
> + static int smc_ib_fill_gid_and_mac(struct smc_ib_device *smcibdev, u8 ibport)
> + {
>  -	struct ib_gid_attr gattr;
>  -	int rc;
>  -
>  -	rc = ib_query_gid(smcibdev->ibdev, ibport, 0,
>  -			  &smcibdev->gid[ibport - 1], &gattr);
>  -	if (rc || !gattr.ndev)
>  -		return -ENODEV;
> ++	const struct ib_gid_attr *gattr;
> ++	int rc = 0;
> + 
>  -	memcpy(smcibdev->mac[ibport - 1], gattr.ndev->dev_addr, ETH_ALEN);
>  -	dev_put(gattr.ndev);
>  -	return 0;
> ++	gattr = rdma_get_gid_attr(smcibdev->ibdev, ibport, 0);
> ++	if (IS_ERR(gattr))
> ++		return PTR_ERR(gattr);
> ++	if (!gattr->ndev) {
> ++		rc = -ENODEV;
> ++		goto done;
> ++	}
> ++	smcibdev->gid[ibport - 1] = gattr->gid;
> ++	memcpy(smcibdev->mac[ibport - 1], gattr->ndev->dev_addr, ETH_ALEN);
> ++done:
> ++	rdma_put_gid_attr(gattr);
> ++	return rc;
> + }
> + 
> + /* Create an identifier unique for this instance of SMC-R.
> +  * The MAC-address of the first active registered IB device
> +  * plus a random 2-byte number is used to create this identifier.
> +  * This name is delivered to the peer during connection initialization.
> +  */
> + static inline void smc_ib_define_local_systemid(struct smc_ib_device *smcibdev,
> + 						u8 ibport)
> + {
> + 	memcpy(&local_systemid[2], &smcibdev->mac[ibport - 1],
> + 	       sizeof(smcibdev->mac[ibport - 1]));
> + 	get_random_bytes(&local_systemid[0], 2);
> + }
> + 
> + bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport)
> + {
> + 	return smcibdev->pattr[ibport - 1].state == IB_PORT_ACTIVE;
> + }
> + 
> + static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport)
> + {
> + 	int rc;
> + 
> + 	memset(&smcibdev->pattr[ibport - 1], 0,
> + 	       sizeof(smcibdev->pattr[ibport - 1]));
> + 	rc = ib_query_port(smcibdev->ibdev, ibport,
> + 			   &smcibdev->pattr[ibport - 1]);
> + 	if (rc)
> + 		goto out;
> + 	/* the SMC protocol requires specification of the RoCE MAC address */
> + 	rc = smc_ib_fill_gid_and_mac(smcibdev, ibport);
> + 	if (rc)
> + 		goto out;
> + 	if (!strncmp(local_systemid, SMC_LOCAL_SYSTEMID_RESET,
> + 		     sizeof(local_systemid)) &&
> + 	    smc_ib_port_active(smcibdev, ibport))
> + 		/* create unique system identifier */
> + 		smc_ib_define_local_systemid(smcibdev, ibport);
> + out:
> + 	return rc;
> + }
> + 
>   /* process context wrapper for might_sleep smc_ib_remember_port_attr */
>   static void smc_ib_port_event_work(struct work_struct *work)
>   {

This is now a conflict between Linus' tree and the rdma tree.

-- 
Cheers,
Stephen Rothwell