From c2ba3db31ef2d9f1e40e7b6c16cf3be3d671d555 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Roger=20Pau=20Monn=C3=A9?= Date: Mon, 11 Aug 2014 14:57:09 +0200 Subject: [PATCH] amd-iommu: disable iommu_hap_pt_share with AMD IOMMUs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 --- xen/drivers/passthrough/amd/iommu_init.c | 8 ++++++++ 1 file changed, 8 insertions(+) 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 ) -- 2.39.5