From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [PATCH 07/10] VMX: handle PML enabling in vmx_vcpu_initialise Date: Fri, 27 Mar 2015 21:12:47 +0000 Message-ID: <5515C7CF.3070907@citrix.com> References: <1427423754-11841-1-git-send-email-kai.huang@linux.intel.com> <1427423754-11841-8-git-send-email-kai.huang@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1427423754-11841-8-git-send-email-kai.huang@linux.intel.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Kai Huang , jbeulich@suse.com, tim@xen.org, kevin.tian@intel.com, yang.z.zhang@intel.com, xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 27/03/15 02:35, Kai Huang wrote: > It's possible domain has already been in log-dirty mode when creating vcpu, in > which case we should enable PML for this vcpu if PML has been enabled for the > domain. > > Signed-off-by: Kai Huang > --- > xen/arch/x86/hvm/vmx/vmx.c | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c > index 453bcc5..fce3aa2 100644 > --- a/xen/arch/x86/hvm/vmx/vmx.c > +++ b/xen/arch/x86/hvm/vmx/vmx.c > @@ -116,6 +116,30 @@ static int vmx_vcpu_initialise(struct vcpu *v) > return rc; > } > > + /* > + * It's rare but still possible that domain has already been in log-dirty > + * mode when vcpu is being created (commented by Tim), in which case we > + * should enable PML for this vcpu if PML has been enabled for the domain, > + * and failure to enable results in failure of creating this vcpu. > + * > + * Note even there's no vcpu created for the domain, vmx_domain_enable_pml > + * will return successful in which case vmx_domain_pml_enabled will also > + * return true. And even this is the first vcpu to be created with > + * vmx_domain_pml_enabled being true, failure of enabling PML still results > + * in failure of creating vcpu, to avoid complicated logic to revert PML > + * style EPT table to non-PML style EPT table. > + */ > + if ( vmx_domain_pml_enabled(v->domain) ) > + { > + if ( (rc = vmx_vcpu_enable_pml(v)) != 0 ) Given the comment here, is the assertion in the top of vmx_vcpu_enable_pml() liable to trip? > + { > + dprintk(XENLOG_ERR, "Failed to enable PML for vcpu %d\n", > + v->vcpu_id); Please use %pv to identify the domain as well as vcpu. ~Andrew > + vmx_destroy_vmcs(v); > + return rc; > + } > + } > + > vpmu_initialise(v); > > vmx_install_vlapic_mapping(v);