From: Eric Auger eric.auger@redhat.com
[ Upstream commit 5f64ce5411b467f1cfea6c63e2494c22b773582b ]
intel_iommu_get_resv_regions() aims to return the list of reserved regions accessible by a given @device. However several devices can access the same reserved memory region and when building the list it is not safe to use a single iommu_resv_region object, whose container is the RMRR. This iommu_resv_region must be duplicated per device reserved region list.
Let's remove the struct iommu_resv_region from the RMRR unit and allocate the iommu_resv_region directly in intel_iommu_get_resv_regions(). We hold the dmar_global_lock instead of the rcu-lock to allow sleeping.
Fixes: 0659b8dc45a6 ("iommu/vt-d: Implement reserved region get/put callbacks") Signed-off-by: Eric Auger eric.auger@redhat.com Reviewed-by: Lu Baolu baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel jroedel@suse.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/intel-iommu.c | 34 +++++++++++++++++----------------- 1 file changed, 17 insertions(+), 17 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index abbbc614c522..9df3b8441227 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -387,7 +387,6 @@ struct dmar_rmrr_unit { u64 end_address; /* reserved end address */ struct dmar_dev_scope *devices; /* target devices */ int devices_cnt; /* target device count */ - struct iommu_resv_region *resv; /* reserved region handle */ };
struct dmar_atsr_unit { @@ -4185,7 +4184,6 @@ static inline void init_iommu_pm_ops(void) {} int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) { struct acpi_dmar_reserved_memory *rmrr; - int prot = DMA_PTE_READ|DMA_PTE_WRITE; struct dmar_rmrr_unit *rmrru; size_t length;
@@ -4199,22 +4197,16 @@ int __init dmar_parse_one_rmrr(struct acpi_dmar_header *header, void *arg) rmrru->end_address = rmrr->end_address;
length = rmrr->end_address - rmrr->base_address + 1; - rmrru->resv = iommu_alloc_resv_region(rmrr->base_address, length, prot, - IOMMU_RESV_DIRECT); - if (!rmrru->resv) - goto free_rmrru;
rmrru->devices = dmar_alloc_dev_scope((void *)(rmrr + 1), ((void *)rmrr) + rmrr->header.length, &rmrru->devices_cnt); if (rmrru->devices_cnt && rmrru->devices == NULL) - goto free_all; + goto free_rmrru;
list_add(&rmrru->list, &dmar_rmrr_units);
return 0; -free_all: - kfree(rmrru->resv); free_rmrru: kfree(rmrru); out: @@ -4432,7 +4424,6 @@ static void intel_iommu_free_dmars(void) list_for_each_entry_safe(rmrru, rmrr_n, &dmar_rmrr_units, list) { list_del(&rmrru->list); dmar_free_dev_scope(&rmrru->devices, &rmrru->devices_cnt); - kfree(rmrru->resv); kfree(rmrru); }
@@ -5206,22 +5197,33 @@ static void intel_iommu_remove_device(struct device *dev) static void intel_iommu_get_resv_regions(struct device *device, struct list_head *head) { + int prot = DMA_PTE_READ | DMA_PTE_WRITE; struct iommu_resv_region *reg; struct dmar_rmrr_unit *rmrr; struct device *i_dev; int i;
- rcu_read_lock(); + down_read(&dmar_global_lock); for_each_rmrr_units(rmrr) { for_each_active_dev_scope(rmrr->devices, rmrr->devices_cnt, i, i_dev) { + struct iommu_resv_region *resv; + size_t length; + if (i_dev != device) continue;
- list_add_tail(&rmrr->resv->list, head); + length = rmrr->end_address - rmrr->base_address + 1; + resv = iommu_alloc_resv_region(rmrr->base_address, + length, prot, + IOMMU_RESV_DIRECT); + if (!resv) + break; + + list_add_tail(&resv->list, head); } } - rcu_read_unlock(); + up_read(&dmar_global_lock);
reg = iommu_alloc_resv_region(IOAPIC_RANGE_START, IOAPIC_RANGE_END - IOAPIC_RANGE_START + 1, @@ -5236,10 +5238,8 @@ static void intel_iommu_put_resv_regions(struct device *dev, { struct iommu_resv_region *entry, *next;
- list_for_each_entry_safe(entry, next, head, list) { - if (entry->type == IOMMU_RESV_MSI) - kfree(entry); - } + list_for_each_entry_safe(entry, next, head, list) + kfree(entry); }
#ifdef CONFIG_INTEL_IOMMU_SVM