----- Original Message ----- > From: "Frank van der Linden" <fllinden@xxxxxxxxxx> > To: "Tigran Mkrtchyan" <tigran.mkrtchyan@xxxxxxx> > Cc: "linux-nfs" <linux-nfs@xxxxxxxxxxxxxxx>, "Anna Schumaker" <anna.schumaker@xxxxxxxxxx>, "Trond Myklebust" > <trond.myklebust@xxxxxxxxxxxxxxx> > Sent: Friday, March 27, 2020 12:16:02 AM > Subject: Re: [PATCH v2 00/13] NFS client user xattr (RFC8276) support > On Thu, Mar 26, 2020 at 08:03:13PM +0100, Mkrtchyan, Tigran wrote: >> The new patchset looks broken to me. >> >> Client quiryes for supported attributes and gets xattr_support bit set: >> >> Mar 26 11:27:07 ani.desy.de kernel: decode_attr_supported: >> bitmask=fcffbfff:40fdbe3e:00040800 >> >> However, the attribute never queries, but client makes is decision: >> >> Mar 26 11:27:07 ani.desy.de kernel: decode_attr_xattrsupport: XATTR >> support=false >> >> The packets can be found here: https://sas.desy.de/index.php/s/GEPiBxPg3eR4aGA >> >> Can you provide packets of your mount/umount round. > > Hi Tigran, > > I looked at your packet dump. It seems like your server only supports 4.1, > not 4.2. xattr support builds on 4.2 (within the rules laid out in > RFC 8178). That's right, this is what rfc8276 says: Note that the XDR code contained in this document depends on types from the NFSv4.2 nfs4_prot.x file [RFC7863]. This includes both nfs types that end with a 4, such as nfs_cookie4, count4, etc., as well as more-generic types, such as opaque and bool. However, xattr support doesn't relays on any functionality provided by v4.2. Moreover, all used data structures (nfs_cookie4, component4, change_info4) defined in nfsv4.0. Thus there are no reasons why even v4.0 server can't support xattrs. > > So, the fsinfo client call, which is just a GETATTR, masks out the 4.2 > fattr bits from server->attr_mask, and just uses the 4.1 bits. Meaning that > xattr_support is not included, and defaults to false. I was expecting something like this, but was unable to find the place where this masking is happening. Tigran. > > The packet dump also indicates that your server advertises the xattr_support > fattr as supported, even though it's in a 4.1 session, which would not > be correct. > > - Frank
