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Subject: [PATCH 06/34] KVM: PPC: Return '1' unconditionally for KVM_CAP_SYNC_MMU
Date:   Sun,  5 Nov 2023 17:30:09 +0100
Message-ID: <20231105163040.14904-7-pbonzini@redhat.com>
In-Reply-To: <20231105163040.14904-1-pbonzini@redhat.com>
References: <20231105163040.14904-1-pbonzini@redhat.com>
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From: Sean Christopherson <seanjc@google.com>

Advertise that KVM's MMU is synchronized with the primary MMU for all
flavors of PPC KVM support, i.e. advertise that the MMU is synchronized
when CONFIG_KVM_BOOK3S_HV_POSSIBLE=y but the VM is not using hypervisor
mode (a.k.a. PR VMs).  PR VMs, via kvm_unmap_gfn_range_pr(), do the right
thing for mmu_notifier invalidation events, and more tellingly, KVM
returns '1' for KVM_CAP_SYNC_MMU when CONFIG_KVM_BOOK3S_HV_POSSIBLE=n
and CONFIG_KVM_BOOK3S_PR_POSSIBLE=y, i.e. KVM already advertises a
synchronized MMU for PR VMs, just not when CONFIG_KVM_BOOK3S_HV_POSSIBLE=y.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20231027182217.3615211-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/powerpc/kvm/powerpc.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index b0a512ede764..8d3ec483bc2b 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -635,11 +635,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 #if !defined(CONFIG_MMU_NOTIFIER) || !defined(KVM_ARCH_WANT_MMU_NOTIFIER)
 		BUILD_BUG();
 #endif
-#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
-		r = hv_enabled;
-#else
 		r = 1;
-#endif
 		break;
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	case KVM_CAP_PPC_HTAB_FD:
-- 
2.39.1