[PATCH v6 0/2] KVM: PPC: Book3S HV: Nested guest state sanitising changes

[Fabiano Rosas]

This series aims to stop contaminating the l2_hv structure with bits
that might have come from L1 state.

Patch 1 makes l2_hv read-only (mostly). It is now only changed when we
explicitly want to pass information to L1.

Patch 2 makes sure that L1 is not forwarded HFU interrupts when the
host has decided to disable any facilities (theoretical for now, since
HFSCR bits are always the same between L1/Ln).

Changes since v5:

- patch 2 now reads the instruction earlier at the nested exit handler
  to allow the guest to retry if the load fails.

v5:

- moved setting of the Cause bits under BOOK3S_INTERRUPT_H_FAC_UNAVAIL.

https://lkml.kernel.org/r/20210726201710.2432874-1-farosas@linux.ibm.com

v4:

- now passing lpcr separately into load_l2_hv_regs to solve the
  conflict with commit a19b70abc69a ("KVM: PPC: Book3S HV: Nested move
  LPCR sanitising to sanitise_hv_regs");

- patch 2 now forwards a HEAI instead of injecting a Program.

https://lkml.kernel.org/r/20210722221240.2384655-1-farosas@linux.ibm.com

v3:

- removed the sanitise functions;
- moved the entry code into a new load_l2_hv_regs and the exit code
  into the existing save_hv_return_state;
- new patch: removes the cause bits when L0 has disabled the
  corresponding facility.

https://lkml.kernel.org/r/20210415230948.3563415-1-farosas@linux.ibm.com

v2:

- made the change more generic, not only applies to hfscr anymore;
- sanitisation is now done directly on the vcpu struct, l2_hv is left
  unchanged.

https://lkml.kernel.org/r/20210406214645.3315819-1-farosas@linux.ibm.com

v1:
https://lkml.kernel.org/r/20210305231055.2913892-1-farosas@linux.ibm.com

Fabiano Rosas (2):
  KVM: PPC: Book3S HV: Sanitise vcpu registers in nested path
  KVM: PPC: Book3S HV: Stop forwarding all HFUs to L1

 arch/powerpc/kvm/book3s_hv.c        |  13 ++++
 arch/powerpc/kvm/book3s_hv_nested.c | 117 ++++++++++++++++------------
 2 files changed, 79 insertions(+), 51 deletions(-)

-- 
2.29.2