Hi, These are possibly related to https://bugzilla.kernel.org/show_bug.cgi?id=202435 mentioning in https://bugzilla.kernel.org/show_bug.cgi?id=202435#c3 that upstream commits 53da6a53e1d4 "nfsd4: catch some false session retries" (may also need preceding 085def3ade52 "nfsd4: fix cached replies to solo SEQUENCE compounds") likely fix the issue.
Salvatore