From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: [v2][PATCH 1/1] xen:vtd: missing RMRR mapping while share EPT Date: Thu, 24 Jul 2014 09:57:13 +0100 Message-ID: <53D0CA69.6090500@citrix.com> References: <1406191841-5258-1-git-send-email-tiejun.chen@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1406191841-5258-1-git-send-email-tiejun.chen@intel.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: Tiejun Chen , JBeulich@suse.com, yang.z.zhang@intel.com, kevin.tian@intel.com Cc: xen-devel@lists.xen.org List-Id: xen-devel@lists.xenproject.org On 24/07/14 09:50, Tiejun Chen wrote: > intel_iommu_map_page() does nothing if VT-d shares EPT page table. > So rmrr_identity_mapping() never create RMRR mapping but in some > cases like some GFX drivers it still need to access RMRR. > > Here we will create those RMRR mappings even in shared EPT case. > > Signed-off-by: Tiejun Chen > --- > xen/drivers/passthrough/vtd/iommu.c | 18 ++++++++++++++++-- > 1 file changed, 16 insertions(+), 2 deletions(-) > > v2: > > * Fix coding style. > * Still need to abide intel_iommu_map_page(), so we should do nothing > if dom0 and iommu supports pass thru. > > diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c > index 042b882..aca79db 100644 > --- a/xen/drivers/passthrough/vtd/iommu.c > +++ b/xen/drivers/passthrough/vtd/iommu.c > @@ -41,6 +41,7 @@ > #include "extern.h" > #include "vtd.h" > #include "../ats.h" > +#include "../../../arch/x86/mm/mm-locks.h" ~Andrew > > struct mapped_rmrr { > struct list_head list; > @@ -1842,6 +1843,7 @@ static int rmrr_identity_mapping(struct domain *d, > unsigned long base_pfn, end_pfn; > struct mapped_rmrr *mrmrr; > struct hvm_iommu *hd = domain_hvm_iommu(d); > + struct p2m_domain *p2m = p2m_get_hostp2m(d); > > ASSERT(spin_is_locked(&pcidevs_lock)); > ASSERT(rmrr->base_address < rmrr->end_address); > @@ -1867,8 +1869,20 @@ static int rmrr_identity_mapping(struct domain *d, > > while ( base_pfn < end_pfn ) > { > - if ( intel_iommu_map_page(d, base_pfn, base_pfn, > - IOMMUF_readable|IOMMUF_writable) ) > + if ( iommu_use_hap_pt(d) && (!iommu_passthrough || > + !is_hardware_domain(d)) ) > + { > + p2m_lock(p2m); > + if ( p2m_set_entry(p2m, base_pfn, _mfn(base_pfn), PAGE_ORDER_4K, > + p2m_mmio_direct, p2m_access_rw) ) > + { > + p2m_unlock(p2m); > + return -1; > + } > + p2m_unlock(p2m); > + } > + else if ( intel_iommu_map_page(d, base_pfn, base_pfn, > + IOMMUF_readable|IOMMUF_writable) ) > return -1; > base_pfn++; > }