From: Roger Pau Monné Date: Mon, 11 Aug 2014 12:57:09 +0000 (+0200) Subject: amd-iommu: disable iommu_hap_pt_share with AMD IOMMUs X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~4541 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=c2ba3db31ef2d9f1e40e7b6c16cf3be3d671d555;p=xen.git amd-iommu: disable iommu_hap_pt_share with AMD IOMMUs According to the comment in p2m.h, AMD IOMMUs don't work correctly with page types different than p2m_ram_rw when the p2m is shared between HAP and IOMMU, so disable this sharing when using AMD IOMMUs. Signed-off-by: Roger Pau Monné Acked-by Suravee Suthikulpanit --- diff --git a/xen/drivers/passthrough/amd/iommu_init.c b/xen/drivers/passthrough/amd/iommu_init.c index b2f74ef000..56bda00afd 100644 --- a/xen/drivers/passthrough/amd/iommu_init.c +++ b/xen/drivers/passthrough/amd/iommu_init.c @@ -1255,6 +1255,14 @@ int __init amd_iommu_init(void) if ( iterate_ivrs_mappings(amd_iommu_setup_device_table) != 0 ) goto error_out; + /* + * Disable sharing HAP page tables with AMD IOMMU, + * since it only supports p2m_ram_rw, and this would + * prevent doing IO to/from mapped grant frames. + */ + iommu_hap_pt_share = 0; + printk(XENLOG_DEBUG "AMD-Vi: Disabled HAP memory map sharing with IOMMU\n"); + /* per iommu initialization */ for_each_amd_iommu ( iommu ) if ( amd_iommu_init_one(iommu) != 0 )