iommu/vt-d: fix a race window in allocating domain ID for virtual machines (18d99165) · Commits · 戴 / test

Function intel_iommu_domain_init() may be concurrently called by upper layer without serialization, so use atomic_t to protect domain id allocation. Signed-off-by:

Jiang Liu <jiang.liu@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by:

Joerg Roedel <joro@8bytes.org>

drivers/iommu/intel-iommu.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -3877,7 +3877,7 @@ static void vm_domain_remove_all_dev_info(struct dmar_domain *domain)
		}

		/* domain id for virtual machine, it won't be set in context */
		static unsigned long vm_domid;
		static atomic_t vm_domid = ATOMIC_INIT(0);

		static struct dmar_domain *iommu_alloc_vm_domain(void)
		{
		@@ -3887,7 +3887,7 @@ static struct dmar_domain *iommu_alloc_vm_domain(void)
		if (!domain)
		return NULL;

		domain->id = vm_domid++;
		domain->id = atomic_inc_return(&vm_domid);
		domain->nid = -1;
		memset(domain->iommu_bmp, 0, sizeof(domain->iommu_bmp));
		domain->flags = DOMAIN_FLAG_VIRTUAL_MACHINE;

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