From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chen, Tiejun" Subject: Re: [v5][PATCH 10/16] tools: introduce some new parameters to set rdm policy Date: Tue, 07 Jul 2015 20:31:20 +0800 Message-ID: <559BC698.9070409@intel.com> References: <1436249837-14747-1-git-send-email-tiejun.chen@intel.com> <1436249837-14747-11-git-send-email-tiejun.chen@intel.com> <21915.48185.41230.587033@mariner.uk.xensource.com> <559BC02A.6090604@intel.com> <21915.49816.559101.864128@mariner.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <21915.49816.559101.864128@mariner.uk.xensource.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: Ian Jackson Cc: Stefano Stabellini , Wei Liu , Ian Campbell , xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org > [Later:] >> As I discussed with Campbell we'd like not to expose "none" in xl level >> since this is equivalent to that case we don't set anything. > > I think this observation of mine applies to the libxl API level too. Sorry I don't know what I should do at this point. > > >>>> Default per-device RDM policy is 'strict', while default global >>>> RDM policy is 'relaxed'. And the per-device policy would override >>>> the global policy like others. >>> >>> I don't think these two sentences can both be true. If the per-device >>> policy overrides the global policy, then the per-device policy must >>> have at least three values: `strict', `relaxed', and `not set' >>> (implicitly using global policy). >> >> Yeah. The per-device policy is first set as the global policy. This >> behavior is same as other pci option. Please see the last patch, > > OK, then can you please amend the commit message to be true :-). Sure. > > >>> This suggests that the default is "do the dangerous thing". That >>> doesn't seem right. >> >> As I discussed with Campbell we'd like not to expose "none" in xl level >> since this is equivalent to that case we don't set anything. > > That's not really an answer to what I have said, I think. > > Why is the default the option that the documentation recommends to > avoid ? I mean not all devices really needs this option and actually these devices are very rare. Currently just IGD GFX needs this consideration so we'd like to make "none" as a default value. > >> "none" means we have a chance to work as before since not all devices >> own RDM. But as I said above this is same as !rdm. > > Are we expecting many existing devices, and existing setups, to break > if we don't make the default be to ignore the problem ? > If we don't set anything we don't hope you can ignore this existing problem. Thanks Tiejun