[RFC PATCH v12 04/33] KVM: PPC: Return '1' unconditionally for KVM_CAP_SYNC_MMU
From: Sean Christopherson <seanjc@google.com>
Date: 2023-09-14 02:11:50
Also in:
kvm, kvm-riscv, kvmarm, linux-arm-kernel, linux-fsdevel, linux-mips, linux-mm, linux-riscv, linuxppc-dev, lkml
Subsystem:
kernel virtual machine for powerpc (kvm/powerpc), linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
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> --- 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:
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2.42.0.283.g2d96d420d3-goog