> -----Original Message----- > From: Wei Liu [mailto:wei.l...@citrix.com] > Sent: 09 October 2018 15:57 > To: xen-devel@lists.xenproject.org > Cc: Paul Durrant <paul.durr...@citrix.com>; Jan Beulich > <jbeul...@suse.com>; Roger Pau Monne <roger....@citrix.com>; Wei Liu > <wei.l...@citrix.com>; Kevin Tian <kevin.t...@intel.com> > Subject: [PATCH v2] x86/vtd: fix IOMMU share PT destruction path > > Commit 2916951c1 ("mm / iommu: include need_iommu() test in > iommu_use_hap_pt()") included need_iommu() in iommu_use_hap_pt and > 91d4eca7add ("mm / iommu: split need_iommu() into has_iommu_pt() and > need_iommu_pt_sync()") made things finer grain by spliting need_iommu > into three states. > > The destruction path can't use iommu_use_hap_pt because at the point > platform op is called, IOMMU is either already switched to or has > always been in disabled state, and the shared PT test would always be > false. > > Signed-off-by: Wei Liu <wei.l...@citrix.com>
Reviewed-by: Paul Durrant <paul.durr...@citrix.com> > --- > v2: fix bug and update comment. > --- > xen/drivers/passthrough/vtd/iommu.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/xen/drivers/passthrough/vtd/iommu.c > b/xen/drivers/passthrough/vtd/iommu.c > index f94b522c73..4d1ff10817 100644 > --- a/xen/drivers/passthrough/vtd/iommu.c > +++ b/xen/drivers/passthrough/vtd/iommu.c > @@ -1752,7 +1752,17 @@ static void iommu_domain_teardown(struct domain *d) > xfree(mrmrr); > } > > - if ( iommu_use_hap_pt(d) ) > + ASSERT(iommu_enabled); > + > + /* > + * We can't use iommu_use_hap_pt here because either IOMMU state > + * is already changed to IOMMU_STATUS_disabled at this point or > + * has always been IOMMU_STATUS_disabled. > + * > + * We also need to test if HAP is enabled because PV guests can > + * enter this path too. > + */ > + if ( hap_enabled(d) && iommu_hap_pt_share ) > return; > > spin_lock(&hd->arch.mapping_lock); > -- > 2.11.0 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
