> -----Original Message----- > From: Tian, Kevin [mailto:[email protected]] > Sent: 21 June 2018 08:21 > To: Paul Durrant <[email protected]>; [email protected] > Cc: Andrew Cooper <[email protected]>; George Dunlap > <[email protected]>; Ian Jackson <[email protected]>; Jan > Beulich <[email protected]>; Julien Grall <[email protected]>; Konrad > Rzeszutek Wilk <[email protected]>; Stefano Stabellini > <[email protected]>; Tim (Xen.org) <[email protected]>; Wei Liu > <[email protected]> > Subject: RE: [PATCH v3 2/2] VT-d: reconcile iommu_inclusive_mapping and > iommu=dom0-strict > > > From: Paul Durrant [mailto:[email protected]] > > Sent: Saturday, June 16, 2018 12:31 AM > > > > The documentation for the iommu_inclusive_mapping Xen command line > > option > > states: > > > > "Use this to work around firmware issues providing incorrect RMRR > > entries" > > > > Unfortunately this workaround does not function correctly if the dom0- > > strict > > iommu option is also specified. > > > > The documentation goes on to say: > > > > "Rather than only mapping RAM pages for IOMMU accesses for Dom0, with > > this > > option all pages up to 4GB, not marked as unusable in the E820 table, will > > get a mapping established." > > > > This patch modifies the VT-d hardware domain initialization code such that > > the workaround will continue to function in dom0-strict mode, by mapping > > all pages not marked as unusable *unless* they are RAM pages not > > assigned > > to dom0. > > > > NOTE: This patch modifies the test in drivers/passthrough/vtd/iommu.c > > from > > need_iommu() to is_pv_domain() since dom0-strict implies > > need_iommu() > > so we no longer want to gate invocation od vtd_set_hwdom_mapping() > > od->of
Good spot. Can this be fixed up at commit please? Paul > > > on that. > > It also exports the iommu_dom0_strict flag so that the implementation > > of vtd_set_hwdom_mapping() can test it explicitly. It would be > > possible to test need_iommu() instead, but it is more illustrative > > to test the original flag rather than one of its side-effects. > > > > Signed-off-by: Paul Durrant <[email protected]> > > Reviewed-by: Roger Pau Monne <[email protected]> > > Acked-by: Kevin Tian <[email protected]> _______________________________________________ Xen-devel mailing list [email protected] https://lists.xenproject.org/mailman/listinfo/xen-devel
