[PATCH 1/1] iommu/vt-d: Fix incorrect pci_for_each_dma_alias() for non-PCI devices

From: Lu Baolu
Date: Fri Oct 11 2024 - 23:12:12 EST


Previously, the domain_context_clear() function incorrectly called
pci_for_each_dma_alias() to set up context entries for non-PCI devices.
This could lead to kernel hangs or other unexpected behavior.

Add a check to only call pci_for_each_dma_alias() for PCI devices. For
non-PCI devices, domain_context_clear_one() is called directly.

Reported-by: Todd Brandt <todd.e.brandt@xxxxxxxxx>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219363
Fixes: 9a16ab9d6402 ("iommu/vt-d: Make context clearing consistent with context mapping")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/iommu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 9f6b0780f2ef..e860bc9439a2 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -3340,8 +3340,10 @@ static int domain_context_clear_one_cb(struct pci_dev *pdev, u16 alias, void *op
*/
static void domain_context_clear(struct device_domain_info *info)
{
- if (!dev_is_pci(info->dev))
+ if (!dev_is_pci(info->dev)) {
domain_context_clear_one(info, info->bus, info->devfn);
+ return;
+ }

pci_for_each_dma_alias(to_pci_dev(info->dev),
&domain_context_clear_one_cb, info);
--
2.43.0