From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerry Snitselaar Subject: Re: [PATCH v2] iommu/amd: Reserve exclusion range in iova-domain Date: Tue, 2 Apr 2019 13:20:14 -0700 Message-ID: <20190402202014.bzjw6eidksg6vymj@cantor> References: <20190329151037.19112-1-joro@8bytes.org> Reply-To: Jerry Snitselaar Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <20190329151037.19112-1-joro@8bytes.org> Sender: linux-kernel-owner@vger.kernel.org To: Joerg Roedel Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Gary R Hook , Joerg Roedel List-Id: iommu@lists.linux-foundation.org On Fri Mar 29 19, Joerg Roedel wrote: >From: Joerg Roedel > >If a device has an exclusion range specified in the IVRS >table, this region needs to be reserved in the iova-domain >of that device. This hasn't happened until now and can cause >data corruption on data transfered with these devices. > >Treat exclusion ranges as reserved regions in the iommu-core >to fix the problem. > >Fixes: be2a022c0dd0 ('x86, AMD IOMMU: add functions to parse IOMMU memory mapping requirements for devices') >Signed-off-by: Joerg Roedel I have a version of this that applies to 4.4 and 4,9 using the older dm_region code if that would be useful for stable. --8<-- diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 0ad8b7c78a43..f388458624cf 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -3165,11 +3165,14 @@ static void amd_iommu_get_dm_regions(struct device *dev, } region->start = entry->address_start; + region->type = IOMMU_RESV_DIRECT; region->length = entry->address_end - entry->address_start; if (entry->prot & IOMMU_PROT_IR) region->prot |= IOMMU_READ; if (entry->prot & IOMMU_PROT_IW) region->prot |= IOMMU_WRITE; + if (entry->prot & IOMMU_UNITY_MAP_FLAG_EXCL_RANGE) + region->type = IOMMU_RESV_RESERVED; list_add_tail(®ion->list, head); } diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c index 94f1bf772ec9..d84041bc77ac 100644 --- a/drivers/iommu/amd_iommu_init.c +++ b/drivers/iommu/amd_iommu_init.c @@ -1495,6 +1495,9 @@ static int __init init_unity_map_range(struct ivmd_header *m) if (e == NULL) return -ENOMEM; + if (m->flags & IVMD_FLAG_EXCL_RANGE) + init_exclusion_range(m); + switch (m->type) { default: kfree(e); @@ -1541,9 +1544,7 @@ static int __init init_memory_definitions(struct acpi_table_header *table) while (p < end) { m = (struct ivmd_header *)p; - if (m->flags & IVMD_FLAG_EXCL_RANGE) - init_exclusion_range(m); - else if (m->flags & IVMD_FLAG_UNITY_MAP) + if (m->flags & (IVMD_FLAG_UNITY_MAP | IVMD_FLAG_EXCL_RANGE)) init_unity_map_range(m); p += m->length; diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h index b08cf57bf455..31d27eb70565 100644 --- a/drivers/iommu/amd_iommu_types.h +++ b/drivers/iommu/amd_iommu_types.h @@ -324,6 +324,8 @@ #define IOMMU_PROT_IR 0x01 #define IOMMU_PROT_IW 0x02 +#define IOMMU_UNITY_MAP_FLAG_EXCL_RANGE (1 << 2) + /* IOMMU capabilities */ #define IOMMU_CAP_IOTLB 24 #define IOMMU_CAP_NPCACHE 26 diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index a070fa39521a..ef4aa2879952 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -351,6 +351,9 @@ static int iommu_group_create_direct_mappings(struct iommu_group *group, start = ALIGN(entry->start, pg_size); end = ALIGN(entry->start + entry->length, pg_size); + if (entry->type != IOMMU_RESV_DIRECT) + continue; + for (addr = start; addr < end; addr += pg_size) { phys_addr_t phys_addr; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index f28dff313b07..15b7378f67f3 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -115,18 +115,23 @@ enum iommu_attr { DOMAIN_ATTR_MAX, }; +#define IOMMU_RESV_DIRECT (1 << 0) +#define IOMMU_RESV_RESERVED (1 << 1) + /** * struct iommu_dm_region - descriptor for a direct mapped memory region * @list: Linked list pointers * @start: System physical start address of the region * @length: Length of the region in bytes * @prot: IOMMU Protection flags (READ/WRITE/...) + * @type: Type of region (DIRECT, RESERVED) */ struct iommu_dm_region { struct list_head list; phys_addr_t start; size_t length; int prot; + int type; }; #ifdef CONFIG_IOMMU_API -- 2.21.0