Help on kvm_tlb_flush_vmid_ipa usage

Marc Zyngier marc.zyngier at arm.com
Thu Dec 18 11:38:07 PST 2014


On 18/12/14 19:27, Mario Smarduch wrote:
> When this function is called IPA address is used. Looking at the HYP
> implementation it uses the IPA directly in tlbi instructions. But
> reading the TLB maintnance instruction syntax, bit [35:0] should be
> set to IPA[47:12]. I traced the source code but don't see the
> adjustment. I must be missing something given this function is
> fundamental to KVM MMU.

Ermmm... Someone (that is, I) needs a brown paper back again.

diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index b72aa9f..a767f6a 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -1014,6 +1014,7 @@ ENTRY(__kvm_tlb_flush_vmid_ipa)
 	 * Instead, we invalidate Stage-2 for this IPA, and the
 	 * whole of Stage-1. Weep...
 	 */
+	lsr	x1, x1, #12
 	tlbi	ipas2e1is, x1
 	/*
 	 * We have to ensure completion of the invalidation at Stage-2,

	M.
-- 
Jazz is not dead. It just smells funny...



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