diff options
Diffstat (limited to '0004-VT-d-refuse-to-use-IOMMU-with-reserved-CAP.ND-value.patch')
| -rw-r--r-- | 0004-VT-d-refuse-to-use-IOMMU-with-reserved-CAP.ND-value.patch | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/0004-VT-d-refuse-to-use-IOMMU-with-reserved-CAP.ND-value.patch b/0004-VT-d-refuse-to-use-IOMMU-with-reserved-CAP.ND-value.patch new file mode 100644 index 0000000..c566888 --- /dev/null +++ b/0004-VT-d-refuse-to-use-IOMMU-with-reserved-CAP.ND-value.patch @@ -0,0 +1,49 @@ +From b378ee56c7e0bb5eeb35dcc55b3d29e5f50eb566 Mon Sep 17 00:00:00 2001 +From: Jan Beulich <jbeulich@suse.com> +Date: Tue, 7 Jun 2022 13:58:16 +0200 +Subject: [PATCH 04/32] VT-d: refuse to use IOMMU with reserved CAP.ND value +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +The field taking the value 7 (resulting in 18-bit DIDs when using the +calculation in cap_ndoms(), when the DID fields are only 16 bits wide) +is reserved. Instead of misbehaving in case we would encounter such an +IOMMU, refuse to use it. + +Signed-off-by: Jan Beulich <jbeulich@suse.com> +Reviewed-by: Roger Pau Monné <roger.pau@citrix.com> +Reviewed-by: Kevin Tian <kevin.tian@intel.com> +master commit: a1545fbf45c689aff39ce76a6eaa609d32ef72a7 +master date: 2022-04-20 10:54:26 +0200 +--- + xen/drivers/passthrough/vtd/iommu.c | 4 +++- + 1 file changed, 3 insertions(+), 1 deletion(-) + +diff --git a/xen/drivers/passthrough/vtd/iommu.c b/xen/drivers/passthrough/vtd/iommu.c +index 93dd8aa643aa..8975c1de61bc 100644 +--- a/xen/drivers/passthrough/vtd/iommu.c ++++ b/xen/drivers/passthrough/vtd/iommu.c +@@ -1279,8 +1279,11 @@ int __init iommu_alloc(struct acpi_drhd_unit *drhd) + + quirk_iommu_caps(iommu); + ++ nr_dom = cap_ndoms(iommu->cap); ++ + if ( cap_fault_reg_offset(iommu->cap) + + cap_num_fault_regs(iommu->cap) * PRIMARY_FAULT_REG_LEN >= PAGE_SIZE || ++ ((nr_dom - 1) >> 16) /* I.e. cap.nd > 6 */ || + ecap_iotlb_offset(iommu->ecap) >= PAGE_SIZE ) + { + printk(XENLOG_ERR VTDPREFIX "IOMMU: unsupported\n"); +@@ -1305,7 +1308,6 @@ int __init iommu_alloc(struct acpi_drhd_unit *drhd) + vtd_ops.sync_cache = sync_cache; + + /* allocate domain id bitmap */ +- nr_dom = cap_ndoms(iommu->cap); + iommu->domid_bitmap = xzalloc_array(unsigned long, BITS_TO_LONGS(nr_dom)); + if ( !iommu->domid_bitmap ) + return -ENOMEM; +-- +2.35.1 + |