Commit 93fa50f6 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
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KVM: x86/mmu: Batch TLB flushes from TDP MMU for MMU notifier change_spte 



Batch TLB flushes (with other MMUs) when handling ->change_spte()
notifications in the TDP MMU.  The MMU notifier path in question doesn't
allow yielding and correcty flushes before dropping mmu_lock.

Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
Reviewed-by: default avatarBen Gardon <bgardon@google.com>
Message-Id: <20220226001546.360188-9-seanjc@google.com>
Reviewed-by: default avatarMingwei Zhang <mizhang@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent c8e5a0d0

arch/x86/kvm/mmu/tdp_mmu.c

+6 −7
Original line number Diff line number Diff line
@@ -1226,13 +1226,12 @@ static bool set_spte_gfn(struct kvm *kvm, struct tdp_iter *iter, 
 */

bool kvm_tdp_mmu_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)

{

	bool flush = kvm_tdp_mmu_handle_gfn(kvm, range, set_spte_gfn);



	/* FIXME: return 'flush' instead of flushing here. */

	if (flush)

		kvm_flush_remote_tlbs_with_address(kvm, range->start, 1);



	return false;

	/*

	 * No need to handle the remote TLB flush under RCU protection, the

	 * target SPTE _must_ be a leaf SPTE, i.e. cannot result in freeing a

	 * shadow page.  See the WARN on pfn_changed in __handle_changed_spte().

	 */

	return kvm_tdp_mmu_handle_gfn(kvm, range, set_spte_gfn);

}



/*