Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752815AbaKEBuq (ORCPT ); Tue, 4 Nov 2014 20:50:46 -0500 Received: from mga02.intel.com ([134.134.136.20]:46853 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751506AbaKEBup (ORCPT ); Tue, 4 Nov 2014 20:50:45 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,316,1413270000"; d="scan'208";a="602422611" Message-ID: <54598270.2050302@intel.com> Date: Wed, 05 Nov 2014 09:50:40 +0800 From: "Chen, Tiejun" User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH] kvm: x86: vmx: avoid returning bool to distinguish success from error References: <1415122394-31986-1-git-send-email-pbonzini@redhat.com> <545980A9.8030405@intel.com> In-Reply-To: <545980A9.8030405@intel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/11/5 9:43, Chen, Tiejun wrote: > On 2014/11/5 1:33, Paolo Bonzini wrote: >> Return a negative error code instead, and WARN() when we should be >> covering >> the entire 2-bit space of vmcs_field_type's return value. For increased >> robustness, add a BUILD_BUG_ON checking the range of >> vmcs_field_to_offset. >> >> Suggested-by: Tiejun Chen >> Signed-off-by: Paolo Bonzini >> --- >> arch/x86/kvm/vmx.c | 51 [snip] >> @@ -6576,6 +6581,9 @@ static void copy_shadow_to_vmcs12(struct >> vcpu_vmx *vmx) >> case VMCS_FIELD_TYPE_NATURAL_WIDTH: >> field_value = vmcs_readl(field); >> break; >> + default: >> + WARN_ON(1); >> + continue; > > 'continue' versus 'break'? > > Thanks > Tiejun > >> } >> vmcs12_write_any(&vmx->vcpu, field, field_value); >> } >> @@ -6621,6 +6629,9 @@ static void copy_vmcs12_to_shadow(struct >> vcpu_vmx *vmx) >> case VMCS_FIELD_TYPE_NATURAL_WIDTH: >> vmcs_writel(field, (long)field_value); >> break; >> + default: >> + WARN_ON(1); >> + break; >> } >> } >> } >> @@ -6659,7 +6670,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) >> /* Decode instruction info and find the field to read */ >> field = kvm_register_readl(vcpu, (((vmx_instruction_info) >> 28) >> & 0xf)); >> /* Read the field, zero-extended to a u64 field_value */ >> - if (!vmcs12_read_any(vcpu, field, &field_value)) { >> + if (vmcs12_read_any(vcpu, field, &field_value) < 0) { >> nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT); >> skip_emulated_instruction(vcpu); >> return 1; >> Looks we're missing another place, --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -6601,7 +6601,7 @@ static int handle_vmwrite(struct kvm_vcpu *vcpu) return 1; } - if (!vmcs12_write_any(vcpu, field, field_value)) { + if (vmcs12_write_any(vcpu, field, field_value) < 0) { nested_vmx_failValid(vcpu, VMXERR_UNSUPPORTED_VMCS_COMPONENT); skip_emulated_instruction(vcpu); return 1; Thanks Tiejun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/