Suppose I open/create a file over pNFS and am given a WRITE delegation. I then chmod the file (as rsync is wont to do) so the delegation is immediately returned. I then proceed to write, which triggers a LAYOUT_GET request. The stateid for that request it taken from state->stateid, which is still the delegation stateid. Naturally it gets NFS4ERR_BAD_STATEID. When an OPEN is given a delegation, the delegation stateid gets copied into ->stateid and the open stateid is left in ->open_stateid. When the delegation is returned, this it done by inode, not open_state, so it doesn't have easy access to reset the ->stateid. It could find all the open_states and fix them up I guess it .... Other than this usage in pnfs (which dates back to commit b1f69b754e and is, I believe, incorrect) the ->stateid is *only* used to help find the write state to recover when an error is reported and the state needs to be recovered (... though the usage in nfs4_do_handle_exception() introduced by 272289a3df is a bit different). Anyway, no other code uses it when choosing a stateid to send in a request. So no other code inadvertently uses the delegation stateid after it has been returned. How should this be fixed? - have nfs_start_delegation_return() iterated over all open states and copy the open_stateid over the stateid?? - have pnfs_update_layout() use ->open_stateid rather than ->stateid ?? I suspect that would be wrong. - have pnfs_update_layout() use ->open_stateid if NFS_I()->delegation is NULL ?? Something else? The last seems easiest, but I'm not certain it is best. Thanks, NeilBrown
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