Re: [PATCH 1/2] iommu/vt-d: Detach domain before using a private one

From: Lu Baolu
Date: Thu Aug 08 2019 - 20:49:34 EST


Hi Alex,

On 8/9/19 4:10 AM, Alex Williamson wrote:
On Tue, 6 Aug 2019 08:14:08 +0800
Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> wrote:

When the default domain of a group doesn't work for a device,
the iommu driver will try to use a private domain. The domain
which was previously attached to the device must be detached.

Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Fixes: 942067f1b6b97 ("iommu/vt-d: Identify default domains replaced with private")
Reported-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Link: https://lkml.org/lkml/2019/8/2/1379
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---

Tested-by: Alex Williamson <alex.williamson@xxxxxxxxxx>

This series resolves the issue I reported against:
iommu/vt-d: Cleanup get_valid_domain_for_dev()

Thank you for testing it.

Best regards,
Baolu


Thanks,
Alex

drivers/iommu/intel-iommu.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 3e22fa6ae8c8..37259b7f95a7 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -3449,6 +3449,7 @@ static bool iommu_need_mapping(struct device *dev)
dmar_domain = to_dmar_domain(domain);
dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
}
+ dmar_remove_one_dev_info(dev);
get_private_domain_for_dev(dev);
}
@@ -4803,7 +4804,8 @@ static void dmar_remove_one_dev_info(struct device *dev)
spin_lock_irqsave(&device_domain_lock, flags);
info = dev->archdata.iommu;
- __dmar_remove_one_dev_info(info);
+ if (info)
+ __dmar_remove_one_dev_info(info);
spin_unlock_irqrestore(&device_domain_lock, flags);
}
@@ -5281,6 +5283,7 @@ static int intel_iommu_add_device(struct device *dev)
if (device_def_domain_type(dev) == IOMMU_DOMAIN_IDENTITY) {
ret = iommu_request_dm_for_dev(dev);
if (ret) {
+ dmar_remove_one_dev_info(dev);
dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
domain_add_dev_info(si_domain, dev);
dev_info(dev,
@@ -5291,6 +5294,7 @@ static int intel_iommu_add_device(struct device *dev)
if (device_def_domain_type(dev) == IOMMU_DOMAIN_DMA) {
ret = iommu_request_dma_domain_for_dev(dev);
if (ret) {
+ dmar_remove_one_dev_info(dev);
dmar_domain->flags |= DOMAIN_FLAG_LOSE_CHILDREN;
if (!get_private_domain_for_dev(dev)) {
dev_warn(dev,