From: Edgar E. Iglesias Date: Fri, 8 May 2015 07:10:10 +0000 (+1000) Subject: xen/iommu: arm: Use p2m_ipa_bits as stage2 input size X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~3259 X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/%22/%22http:/www.example.com/cgi/%22?a=commitdiff_plain;h=3de112bcac21daecf42c2cdaaef7c5b8e21489d5;p=xen.git xen/iommu: arm: Use p2m_ipa_bits as stage2 input size The Stage2 input-size must match what the CPU uses because the SMMU and the CPU share page-tables. Test that the SMMU supports the P2M IPA bit size, use it if supported or bail out if not. Reviewed-by: Julien Grall Signed-off-by: Edgar E. Iglesias Acked-by: Ian Campbell --- diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c index 65de50bebe..6cc439443b 100644 --- a/xen/drivers/passthrough/arm/smmu.c +++ b/xen/drivers/passthrough/arm/smmu.c @@ -2230,8 +2230,14 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) size = arm_smmu_id_size_to_bits((id >> ID2_IAS_SHIFT) & ID2_IAS_MASK); smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size); - /* Xen: Stage-2 input size is not restricted */ - smmu->s2_input_size = size; + /* Xen: Stage-2 input size has to match p2m_ipa_bits. */ + if (size < p2m_ipa_bits) { + dev_err(smmu->dev, + "P2M IPA size not supported (P2M=%u SMMU=%lu)!\n", + p2m_ipa_bits, size); + return -ENODEV; + } + smmu->s2_input_size = p2m_ipa_bits; #if 0 /* Stage-2 input size limited due to pgd allocation (PTRS_PER_PGD) */ #ifdef CONFIG_64BIT