Merge branch 'topic/ppc-kvm' of https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux into HEAD

Fix conflicts between memslot overhaul and commit 511d25d6b7 ("KVM:
PPC: Book3S: Suppress warnings when allocating too big memory slots")
from the powerpc tree.

arch/powerpc/kvm/Kconfig

@@ -131,6 +131,21 @@ config KVM_BOOK3S_HV_EXIT_TIMING
 
 	  If unsure, say N.
 
+config KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND
+	bool "Nested L0 host workaround for L1 KVM host PMU handling bug" if EXPERT
+	depends on KVM_BOOK3S_HV_POSSIBLE
+	default !EXPERT
+	help
+	  Old nested HV capable Linux guests have a bug where they don't
+	  reflect the PMU in-use status of their L2 guest to the L0 host
+	  while the L2 PMU registers are live. This can result in loss
+          of L2 PMU register state, causing perf to not work correctly in
+	  L2 guests.
+
+	  Selecting this option for the L0 host implements a workaround for
+	  those buggy L1s which saves the L2 state, at the cost of performance
+	  in all nested-capable guest entry/exit.
+
 config KVM_BOOKE_HV
 	bool