Cray's gnilnd is running into a hole in kiov list in Lustre 2.1:

LustreError: 17837:0:(gnilnd_cb.c:594:kgnilnd_setup_phys_buffer()) Can't make payload
contiguous in I/O VM:page 17, offset 0, nob 6350, kiov_offset 0 kiov_len 2254
LustreError: 17837:0:(gnilnd_cb.c:1751:kgnilnd_send()) unable to setup buffer: -22

It used to be that only the first and last page in an IOV were allowed
to be of a offset + length < PAGE_SIZE.

It doesn't have this problem with 1.8 client and 2.1 server.

This problem can be reproduced by "fsx-linux -WR -dn -N 10000 junkfile".

The osc_brw() is never called and the unfragmented pages logic is not exercised in 2.1