On 13/07/2016 00:18, Bandan Das wrote: > v1 of this series posted at https://lkml.org/lkml/2016/6/28/7 > > Changes since v1: > - 1/5 : modify is_shadow_present_pte to check against 0xffffffff > Reasoning provided in commit message. > - 2/5 : Removed 2/5 from v1 since kvm doesn't use execute only. > 3/5 from v1 is now 2/5. Introduce shadow_present_mask that > signifies whether ept execute only is supported. Add/remove some > comments as suggested in v1. > - 3/5 : 4/5 from v1 is now 3/5. > - 4/5 : update_permission_bitmask now sets u=1 only if host doesn't > support ept execute only. > - 5/5 : No change These are the diffs I have after review, do they look okay? diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 190c0559c221..bd2535fdb9eb 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -2524,11 +2524,10 @@ static int set_spte(struct kvm_vcpu *vcpu, u64 *sptep, return 0; /* - * In the non-EPT case, execonly is not valid and so - * the following line is equivalent to spte |= PT_PRESENT_MASK. * For the EPT case, shadow_present_mask is 0 if hardware - * supports it and we honor whatever way the guest set it. - * See: FNAME(gpte_access) in paging_tmpl.h + * supports exec-only page table entries. In that case, + * ACC_USER_MASK and shadow_user_mask are used to represent + * read access. See FNAME(gpte_access) in paging_tmpl.h. */ spte |= shadow_present_mask; if (!speculative) @@ -3923,9 +3922,6 @@ static void update_permission_bitmask(struct kvm_vcpu *vcpu, * clearer. */ smap = cr4_smap && u && !uf && !ff; - } else { - if (shadow_present_mask) - u = 1; } fault = (ff && !x) || (uf && !u) || (wf && !w) || diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 576c47cda1a3..dfef081e76c0 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6120,12 +6120,14 @@ static int handle_ept_violation(struct kvm_vcpu *vcpu) gpa = vmcs_read64(GUEST_PHYSICAL_ADDRESS); trace_kvm_page_fault(gpa, exit_qualification); - /* It is a write fault? */ + /* it is a read fault? */ + error_code = (exit_qualification << 2) & PFERR_USER_MASK; + /* it is a write fault? */ error_code = exit_qualification & PFERR_WRITE_MASK; /* It is a fetch fault? */ error_code |= (exit_qualification << 2) & PFERR_FETCH_MASK; /* ept page table is present? */ - error_code |= (exit_qualification >> 3) & PFERR_PRESENT_MASK; + error_code |= (exit_qualification & 0x38) != 0; vcpu->arch.exit_qualification = exit_qualification; @@ -6474,8 +6476,7 @@ static __init int hardware_setup(void) (enable_ept_ad_bits) ? VMX_EPT_DIRTY_BIT : 0ull, 0ull, VMX_EPT_EXECUTABLE_MASK, cpu_has_vmx_ept_execute_only() ? - 0ull : PT_PRESENT_MASK); - BUILD_BUG_ON(PT_PRESENT_MASK != VMX_EPT_READABLE_MASK); + 0ull : VMX_EPT_READABLE_MASK); ept_set_mmio_spte_mask(); kvm_enable_tdp(); } else -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
