* Mathieu Desnoyers:

Of course, we'd have to implement the whole transaction in assembler
for each architecture.

Could this be hidden ina vDSO call?  It would have to receive a pointer
to the rseq area in addition to other arguments that identify the unlock
operation to be performed.  The advantage is that the kernel would now
the addresses involved, so a single rseq flag should be sufficient.  It
could also vary the LL/SC sequence based on architecture capabilities.

The question is whether we can model the unlock operation so that it's
sufficiently generic.

Thanks,
Florian