From: Alex Williamson Date: Tue, 24 May 2011 16:19:04 +0000 (-0400) Subject: intel-iommu: Only unlink device domains from iommu X-Git-Tag: v2.6.39.2~87 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=26265892ce15ab6637959631b03d25528f817e76;p=thirdparty%2Fkernel%2Fstable.git intel-iommu: Only unlink device domains from iommu commit 9b4554b21ed07e8556405510638171f0c787742a upstream. Commit a97590e5 added unlinking domains from iommus to reciprocate the iommu from domains unlinking that was already done. We actually want to only do this for device domains and never for the static identity map domain or VM domains. The SI domain is special and never freed, while VM domain->id lives in their own special address space, separate from iommu->domain_ids. In the current code, a VM can get domain->id zero, then mark that domain unused when unbound from pci-stub. This leads to DMAR write faults when the device is re-bound to the host driver. Signed-off-by: Alex Williamson Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index b04f84e441532..0eeb797d508e6 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -3422,10 +3422,13 @@ static void domain_remove_one_dev_info(struct dmar_domain *domain, domain_update_iommu_cap(domain); spin_unlock_irqrestore(&domain->iommu_lock, tmp_flags); - spin_lock_irqsave(&iommu->lock, tmp_flags); - clear_bit(domain->id, iommu->domain_ids); - iommu->domains[domain->id] = NULL; - spin_unlock_irqrestore(&iommu->lock, tmp_flags); + if (!(domain->flags & DOMAIN_FLAG_VIRTUAL_MACHINE) && + !(domain->flags & DOMAIN_FLAG_STATIC_IDENTITY)) { + spin_lock_irqsave(&iommu->lock, tmp_flags); + clear_bit(domain->id, iommu->domain_ids); + iommu->domains[domain->id] = NULL; + spin_unlock_irqrestore(&iommu->lock, tmp_flags); + } } spin_unlock_irqrestore(&device_domain_lock, flags);