[PATCH 0/2] KVM: Only use posted interrupts for Fixes/LowPrio MSIs
From: Alexander Graf
Date: Tue Sep 03 2019 - 10:30:15 EST
The MSI-X descriptor has a "delivery mode" field which can be set to
various different targets, such as "Fixed" (default), SMI, NMI or INIT.
Usually when we pass devices into guests, we only ever see this MSI-X
descriptor configured as Fixed, so nobody realized that the other modes
were broken when using posted interrupts.
With posted interrupts, we end up configuring these special modes just
the same as a Fixed interrupt. That means instead of generating an SMI,
we inject a normal GSI into the guest.
Of course, that if completely broken. These two patches attempt to fix
the situation for x86 systems. If anyone has a great idea how to generalize
the filtering though, I'm all ears.
Alexander Graf (2):
KVM: VMX: Disable posted interrupts for odd IRQs
KVM: SVM: Disable posted interrupts for odd IRQs
arch/x86/kvm/svm.c | 16 ++++++++++++++++
arch/x86/kvm/vmx/vmx.c | 22 ++++++++++++++++++++++
2 files changed, 38 insertions(+)
Amazon Development Center Germany GmbH
Geschaeftsfuehrung: Christian Schlaeger, Ralf Herbrich
Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B
Ust-ID: DE 289 237 879