From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Re: [PATCH v2 16/30] x86/cpu: Move set_cpumask() calls into c_early_init() Date: Tue, 16 Feb 2016 07:10:50 -0700 Message-ID: <56C33BFA02000078000D2AAC@prv-mh.provo.novell.com> References: <1454679743-18133-1-git-send-email-andrew.cooper3@citrix.com> <1454679743-18133-17-git-send-email-andrew.cooper3@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1454679743-18133-17-git-send-email-andrew.cooper3@citrix.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Cooper Cc: Xen-devel List-Id: xen-devel@lists.xenproject.org >>> On 05.02.16 at 14:42, wrote: > Before c/s 44e24f8567 "x86: don't call generic_identify() redundantly", the > commandline-provided masks would take effect in Xen's view of the features. > > As the masks got applied after the query for features, the redundant call to > generic_identify() would clobber the pre-masking feature information with the > post-masking information. > > Move the set_cpumask() calls into c_early_init() so their effects take place > before the main query for features in generic_identify(). > > The cpuid_mask_* command line parameters now limit the entire system, a > feature XenServer was relying on for testing purposes. And I continue to view this as a step backwards, and hence can't really approve of this change. And XenServer relying on this for whatever purposes is hardly a good argument here. Jan