iommu/vt-d: Remove misleading "domain 0" test from domain_exit()

bjorn-helgaas · joergroedel · commit f096d6657a77 · 2019-02-11T12:07:06.000+01:00
The "Domain 0 is reserved, so dont process it" comment suggests that a NULL pointer corresponds to domain 0. I don't think that's true, and in any case, every caller supplies a non-NULL domain pointer that has already been dereferenced, so the test is unnecessary. Remove the test for a null "domain" pointer. No functional change intended. This null pointer check was added by 5e98c4b ("Allocation and free functions of virtual machine domain"). Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
@@ -1903,10 +1903,6 @@ static void domain_exit(struct dmar_domain *domain)
 {
 	struct page *freelist;
 
-	/* Domain 0 is reserved, so dont process it */
-	if (!domain)
-		return;
-
 	/* Remove associated devices and clear attached or cached domains */
 	rcu_read_lock();
 	domain_remove_dev_info(domain);
