Il 22/09/2014 11:43, Peter Lieven ha scritto:
This series aims not at touching default behaviour. The default for
max_transfer_length
is 0 (no limit). max_transfer_length is a limit that MUST be satisfied
otherwise the request
will fail. And Patch 2 aims at catching this fail earlier in the stack.
Understood. But the right fix is to avoid that backend limits transpire
into guest ABI, not to catch the limits earlier. So the right fix would
be to implement request splitting.
Since we never had a bug report about this, I'm not pushing to implement
splitting. However, patch 2 is still wrong.
Patch 4 instead is fixing a real bug, so it's very much welcome.
Paolo
Currently, we only
have a limit for iSCSI. Without Patch 2 it would fail after we have send
the command to
the target. And without Patch 4 it may happen that multiwrite_merge
traps the into the limit.
Maybe I should adjust the description of max_transfer_length?