> -----Original Message----- > From: Xen-devel [mailto:xen-devel-boun...@lists.xenproject.org] On Behalf > Of Roger Pau Monné > Sent: 03 August 2018 09:14 > To: Jan Beulich <jbeul...@suse.com> > Cc: Kevin Tian <kevin.t...@intel.com>; Stefano Stabellini > <sstabell...@kernel.org>; Wei Liu <wei.l...@citrix.com>; George Dunlap > <george.dun...@citrix.com>; Andrew Cooper > <andrew.coop...@citrix.com>; Ian Jackson <ian.jack...@citrix.com>; Tim > (Xen.org) <t...@xen.org>; Julien Grall <julien.gr...@arm.com>; Suravee > Suthikulpanit <suravee.suthikulpa...@amd.com>; xen-devel <xen- > de...@lists.xenproject.org>; Brian Woods <brian.wo...@amd.com> > Subject: Re: [Xen-devel] [PATCH v2 2/5] iommu: introduce dom0-iommu > option > > On Thu, Aug 02, 2018 at 02:23:23AM -0600, Jan Beulich wrote: > > >>> On 02.08.18 at 09:46, <kevin.t...@intel.com> wrote: > > >> From: Roger Pau Monne [mailto:roger....@citrix.com] > > >> Sent: Wednesday, August 1, 2018 7:04 PM > > >> --- a/docs/misc/xen-command-line.markdown > > >> +++ b/docs/misc/xen-command-line.markdown > > >> @@ -1150,12 +1150,18 @@ detection of systems known to misbehave > > >> upon accesses to that port. > > >> > > >> > `dom0-passthrough` > > >> > > >> +> **WARNING: This command line option is deprecated, and > superseded > > >> by > > >> +> _dom0-iommu=none_ - using both options in combination is > > >> undefined.** > > >> + > > > > > > in patch description you said 'supersede'... is it better to say that > > > new dom0_iommu is favored if both options are specified than > > > saying 'undefined'? > > > > That would complicate handling (perhaps just slightly, but anyway), > > since we'd have to maintain a second boolean. Without that the > > order on the command line determines behavior. (And I see that in > > the end you've figured that out.) > > > > >> @@ -1198,6 +1204,32 @@ detection of systems known to misbehave > upon > > >> accesses to that port. > > >> > > >> >> Enable IOMMU debugging code (implies `verbose`). > > >> > > >> +### dom0-iommu > > >> +> `= List of [ none | strict | relaxed ]` > > >> + > > >> +> Sub-options are of boolean kind and can be prefixed with `no-` to > effect > > >> the > > >> +> inverse meaning. > > > > > > not important comment, but doesn't "no-none" sound weird? :-) > > > > Only positive (true) values should be permitted for I think all of > > these. I didn't look at the patch yes, so perhaps that's already > > the case. > > For the current set of options introduced in this patch none, strict > or relaxed it doesn't make much sense to allow the no- prefix. > > For options added in later patches (inclusive and reserved) it makes > sense to allow the no- prefix, so that a user can do > 'dom0-iommu=no-inclusive' in order to change the default value. >
But what does that mean? 'no-inclusive' clearly means you don't get the inclusive map, but what do you get instead? Strict? None? Paul > I will make it clear which options allow the no- prefix, and add the > code to parse such prefix when it's needed. > > Roger. > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xenproject.org > https://lists.xenproject.org/mailman/listinfo/xen-devel _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel