On Wed, Mar 9, 2011 at 12:11 PM, Jason Gunthorpe <jguntho...@obsidianresearch.com> wrote: > On Wed, Mar 09, 2011 at 05:47:44PM +0200, Alex Netes wrote: >> Hi Jason, >> >> On 17:29 Tue 01 Mar , Jason Gunthorpe wrote: >> > This value must match the portGUID, so it needs to vary on a per port >> > basis like portGUID and not simply reflect the value opensm acquired >> > during the sweep. >> > >> > Prior to this patch opensm returns the same value for localPortNum for >> > all ports on a HCA, now it returns the correct localPortNum for the >> > portGUID. >> > >> > Also fixes query matching in the same way >> > > >> Spec defines the SA NodeRecord.LocalPortNum field as the number of the link >> port which received this SMP (14.2.5.3). This definition doesn't make any >> sense when it comes to SA. > > I think the spec is pretty sound on this point. The SA is expected to > return SA queries for SMP records that match what is present in the > fabric if the requestor did the SMP query itself. The constraints IBA > places on a NodeInfo SMP query are such that localPortNum and > portGUID must *always* match. You cannot enter on port 1 and query the > NodeInfo for port 2 for a CA. > > So the current SA behavior of returning garbage for localPortNum > is essentially returning a NodeInfo that can never be returned by a > raw SMP query, which is clearly not aligned with the intent of the spec. > > I mispoke a bit in the commit message, opensm returns the localPortNum > it acquired during the sweep *for a random port*, eg it collects and > stores the NodeInfo for the first port it sees, then stores portGUID > and localPortNum seperately. When it generates the SA reply it > corretly replaces the port GUID but uses the random old > localPortNum. This is clearly incorrect. > >> I understand your motivation for the patch and the fact that current >> LocalPortNum query matching in the SM doesn't sound right. So maybe >> IBA spec fine tuning is needed, before applying the patch, so this >> field won't be open to free interpretations. > > I don't think there is really any free interpretation here. For > everything but a switch localPortNum must always reflect the port that > portGUID is associated with.
Unfortunately, this is not always true due to the funky cross (CA and router) port PortInfo queries (but I don't think that query style is used by OpenSM for CA or router ports but allowed in IBA)... -- Hal > This is is what is defined to happen when > the NodeRecord SMP is generated by the SMA, the SA must do the same. > > This causes real problems, without an accurate localPortNumber it is > impossible to associate the portGUID with a port number when doing SA > queries > > Jason > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
