On Sun, May 10, 2020 at 07:46:52PM -0400, Joel Fernandes (Google) wrote: > With current core scheduling patchset, non-threaded IRQ and softirq > victims can leak data from its hyperthread to a sibling hyperthread > running an attacker. > > For MDS, it is possible for the IRQ and softirq handlers to leak data to > either host or guest attackers. For L1TF, it is possible to leak to > guest attackers. There is no possible mitigation involving flushing of > buffers to avoid this since the execution of attacker and victims happen > concurrently on 2 or more HTs. > > The solution in this patch is to monitor the outer-most core-wide > irq_enter() and irq_exit() executed by any sibling. In between these > two, we mark the core to be in a special core-wide IRQ state.
Another possible option is force_irqthreads :-) That would cure it nicely. Anyway, I'll go read this.
