From 2a78f9962565e53b78363eaf516eb052009e8020 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Wed, 25 Sep 2019 15:23:00 +0200 Subject: iommu/amd: Lock code paths traversing protection_domain->dev_list The traversing of this list requires protection_domain->lock to be taken to avoid nasty races with attach/detach code. Make sure the lock is held on all code-paths traversing this list. Reported-by: Filippo Sironi Fixes: 92d420ec028d ("iommu/amd: Relax locking in dma_ops path") Reviewed-by: Filippo Sironi Reviewed-by: Jerry Snitselaar Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index bac4e20a5919..9c26976a0f99 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -1334,8 +1334,12 @@ static void domain_flush_np_cache(struct protection_domain *domain, dma_addr_t iova, size_t size) { if (unlikely(amd_iommu_np_cache)) { + unsigned long flags; + + spin_lock_irqsave(&domain->lock, flags); domain_flush_pages(domain, iova, size); domain_flush_complete(domain); + spin_unlock_irqrestore(&domain->lock, flags); } } @@ -1700,8 +1704,13 @@ static int iommu_map_page(struct protection_domain *dom, ret = 0; out: - if (updated) + if (updated) { + unsigned long flags; + + spin_lock_irqsave(&dom->lock, flags); update_domain(dom); + spin_unlock_irqrestore(&dom->lock, flags); + } /* Everything flushed out, free pages now */ free_page_list(freelist); @@ -1857,8 +1866,12 @@ static void free_gcr3_table(struct protection_domain *domain) static void dma_ops_domain_flush_tlb(struct dma_ops_domain *dom) { + unsigned long flags; + + spin_lock_irqsave(&dom->domain.lock, flags); domain_flush_tlb(&dom->domain); domain_flush_complete(&dom->domain); + spin_unlock_irqrestore(&dom->domain.lock, flags); } static void iova_domain_flush_tlb(struct iova_domain *iovad) @@ -2414,6 +2427,7 @@ static dma_addr_t __map_single(struct device *dev, { dma_addr_t offset = paddr & ~PAGE_MASK; dma_addr_t address, start, ret; + unsigned long flags; unsigned int pages; int prot = 0; int i; @@ -2451,8 +2465,10 @@ out_unmap: iommu_unmap_page(&dma_dom->domain, start, PAGE_SIZE); } + spin_lock_irqsave(&dma_dom->domain.lock, flags); domain_flush_tlb(&dma_dom->domain); domain_flush_complete(&dma_dom->domain); + spin_unlock_irqrestore(&dma_dom->domain.lock, flags); dma_ops_free_iova(dma_dom, address, pages); @@ -2481,8 +2497,12 @@ static void __unmap_single(struct dma_ops_domain *dma_dom, } if (amd_iommu_unmap_flush) { + unsigned long flags; + + spin_lock_irqsave(&dma_dom->domain.lock, flags); domain_flush_tlb(&dma_dom->domain); domain_flush_complete(&dma_dom->domain); + spin_unlock_irqrestore(&dma_dom->domain.lock, flags); dma_ops_free_iova(dma_dom, dma_addr, pages); } else { pages = __roundup_pow_of_two(pages); @@ -3246,9 +3266,12 @@ static bool amd_iommu_is_attach_deferred(struct iommu_domain *domain, static void amd_iommu_flush_iotlb_all(struct iommu_domain *domain) { struct protection_domain *dom = to_pdomain(domain); + unsigned long flags; + spin_lock_irqsave(&dom->lock, flags); domain_flush_tlb_pde(dom); domain_flush_complete(dom); + spin_unlock_irqrestore(&dom->lock, flags); } static void amd_iommu_iotlb_sync(struct iommu_domain *domain, -- cgit v1.2.3