From 7a98205deebfff9fc96f90d9e7b1a334b0bd3e2b Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Fri, 25 Mar 2016 21:19:35 +0800 Subject: [PATCH] KVM: MMU: fix permission_fault() kvm-unit-tests complained about the PFEC is not set properly, e.g,: test pte.rw pte.d pte.nx pde.p pde.rw pde.pse user fetch: FAIL: error code 15 expected 5 Dump mapping: address: 0x123400000000 ------L4: 3e95007 ------L3: 3e96007 ------L2: 2000083 It's caused by the reason that PFEC returned to guest is copied from the PFEC triggered by shadow page table This patch fixes it and makes the logic of updating errcode more clean Signed-off-by: Xiao Guangrong [Do not assume pfec.p=1. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.h | 9 ++++----- arch/x86/kvm/paging_tmpl.h | 2 +- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/arch/x86/kvm/mmu.h b/arch/x86/kvm/mmu.h index b70df72e2b33..66b33b96a31b 100644 --- a/arch/x86/kvm/mmu.h +++ b/arch/x86/kvm/mmu.h @@ -173,10 +173,9 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, int index = (pfec >> 1) + (smap >> (X86_EFLAGS_AC_BIT - PFERR_RSVD_BIT + 1)); bool fault = (mmu->permissions[index] >> pte_access) & 1; + u32 errcode = PFERR_PRESENT_MASK; WARN_ON(pfec & (PFERR_PK_MASK | PFERR_RSVD_MASK)); - pfec |= PFERR_PRESENT_MASK; - if (unlikely(mmu->pkru_mask)) { u32 pkru_bits, offset; @@ -189,15 +188,15 @@ static inline u8 permission_fault(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, pkru_bits = (kvm_read_pkru(vcpu) >> (pte_pkey * 2)) & 3; /* clear present bit, replace PFEC.RSVD with ACC_USER_MASK. */ - offset = pfec - 1 + + offset = (pfec & ~1) + ((pte_access & PT_USER_MASK) << (PFERR_RSVD_BIT - PT_USER_SHIFT)); pkru_bits &= mmu->pkru_mask >> offset; - pfec |= -pkru_bits & PFERR_PK_MASK; + errcode |= -pkru_bits & PFERR_PK_MASK; fault |= (pkru_bits != 0); } - return -(uint32_t)fault & pfec; + return -(u32)fault & errcode; } void kvm_mmu_invalidate_zap_all_pages(struct kvm *kvm); diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 1d971c7553c3..bc019f70e0b6 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -360,7 +360,7 @@ retry_walk: goto error; if (unlikely(is_rsvd_bits_set(mmu, pte, walker->level))) { - errcode |= PFERR_RSVD_MASK | PFERR_PRESENT_MASK; + errcode = PFERR_RSVD_MASK | PFERR_PRESENT_MASK; goto error; } -- 2.20.1