tree d3ceacc8402d97ebc92c03d55e3abcfa7b4a6a66
parent 42de7b9e216728edbe53e0c4513e06fe3d566c5d
author Alexey Kardashevskiy <aik@ozlabs.ru> 1536568151 +1000
committer Michael Ellerman <mpe@ellerman.id.au> 1539061467 +1100

KVM: PPC: Propagate errors to the guest when failed instead of ignoring

At the moment if the PUT_TCE{_INDIRECT} handlers fail to update
the hardware tables, we print a warning once, clear the entry and
continue. This is so as at the time the assumption was that if
a VFIO device is hotplugged into the guest, and the userspace replays
virtual DMA mappings (i.e. TCEs) to the hardware tables and if this fails,
then there is nothing useful we can do about it.

However the assumption is not valid as these handlers are not called for
TCE replay (VFIO ioctl interface is used for that) and these handlers
are for new TCEs.

This returns an error to the guest if there is a request which cannot be
processed. By now the only possible failure must be H_TOO_HARD.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>