From 8ed7b7e9d2a4e208d3c94af3ddbc628317b30409 Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Sat, 22 Jun 2013 17:13:32 +1000 Subject: [PATCH] KVM: PPC: Book3S PR: Fix proto-VSID calculations This makes sure the calculation of the proto-VSIDs used by PR KVM is done with 64-bit arithmetic. Since vcpu3s->context_id[] is int, when we do vcpu3s->context_id[0] << ESID_BITS the shift will be done with 32-bit instructions, possibly leading to significant bits getting lost, as the context id can be up to 524283 and ESID_BITS is 18. To fix this we cast the context id to u64 before shifting. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf --- arch/powerpc/kvm/book3s_64_mmu_host.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c index 3a9a1ac..2c6e7ee 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_host.c +++ b/arch/powerpc/kvm/book3s_64_mmu_host.c @@ -325,9 +325,9 @@ int kvmppc_mmu_init(struct kvm_vcpu *vcpu) return -1; vcpu3s->context_id[0] = err; - vcpu3s->proto_vsid_max = ((vcpu3s->context_id[0] + 1) + vcpu3s->proto_vsid_max = ((u64)(vcpu3s->context_id[0] + 1) << ESID_BITS) - 1; - vcpu3s->proto_vsid_first = vcpu3s->context_id[0] << ESID_BITS; + vcpu3s->proto_vsid_first = (u64)vcpu3s->context_id[0] << ESID_BITS; vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first; kvmppc_mmu_hpte_init(vcpu); -- 2.7.4