Commit 2a78f996 authored by Joerg Roedel's avatar Joerg Roedel
Browse files

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: default avatarFilippo Sironi <sironi@amazon.de>
Fixes: 92d420ec ("iommu/amd: Relax locking in dma_ops path")
Reviewed-by: default avatarFilippo Sironi <sironi@amazon.de>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ab7b2577

drivers/iommu/amd_iommu.c

+24 −1
Original line number Diff line number Diff line
@@ -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,

CRA Git | Maintained and supported by SUSTech CRA and CCSE