From: Tian, Kevin > Sent: 05 May 2016 10:37 ... > > Acutually, we are not aimed at accessing MSI-X table from > > guest. So I think it's safe to passthrough MSI-X table if we > > can make sure guest kernel would not touch MSI-X table in > > normal code path such as para-virtualized guest kernel on PPC64. > > > > Then how do you prevent malicious guest kernel accessing it? Or a malicious guest driver for an ethernet card setting up the receive buffer ring to contain a single word entry that contains the address associated with an MSI-X interrupt and then using a loopback mode to cause a specific packet be received that writes the required word through that address. Remember the PCIe cycle for an interrupt is a normal memory write cycle. David ��.n��������+%������w��{.n�����{���"�)��jg��������ݢj����G�������j:+v���w�m������w�������h�����٥