panic on 4.20 server exporting xfs filesystem

Sun Mar 8 10:30:56 CDT 2015

On Thu, Mar 05, 2015 at 03:47:49PM -0500, J. Bruce Fields wrote:
> nfsd: client 192.168.122.32 failed to respond to layout recall.   Fencing..
> nfsd: fence failed for client 192.168.122.32: -2!
> nfsd: client 192.168.122.32 failed to respond to layout recall.   Fencing..
> nfsd: fence failed for client 192.168.122.32: -2!

There is no userspace elper to do the fencing, so unfortunately this
is expecvted.

> receive_cb_reply: Got unrecognized reply: calldir 0x1 xpt_bc_xprt ffff88005639a000 xid c21abd62

Now this looks like some issue with the low-level callback path.  I've never
seen tis before, but from looking at receive_cb_reply this happens if
xprt_lookup_rqst can't find a rpc_rqst structured for the xid.  Looks like
we might be corrupting the request list / xid allocation somewhere?

I can prepare a patch for you to aid with xid tracing if you want.