Re: [PATCH next] iommu: intel: don't dereference iommu_device if IOMMU_API is not built

[Lu Baolu]

On 10/13/20 3:30 PM, Bartosz Golaszewski wrote:

From: Bartosz Golaszewski <bgolaszew...@baylibre.com>

Since commit c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units
with no supported address widths") dmar.c needs struct iommu_device to
be selected. We can drop this dependency by not dereferencing struct
iommu_device if IOMMU_API is not selected and by reusing the information
stored in iommu->drhd->ignored instead.

This fixes the following build error when IOMMU_API is not selected:

drivers/iommu/intel/dmar.c: In function ‘free_iommu’:
drivers/iommu/intel/dmar.c:1139:41: error: ‘struct iommu_device’ has no member 
named ‘ops’
  1139 |  if (intel_iommu_enabled && iommu->iommu.ops) {
                                                 ^

Fixes: c40aaaac1018 ("iommu/vt-d: Gracefully handle DMAR units with no supported 
address widths")
Signed-off-by: Bartosz Golaszewski <bgolaszew...@baylibre.com>

With commit title adjusted to "iommu/vt-d: Don't dereference
iommu_device if IOMMU_API is not built",

Acked-by: Lu Baolu <baolu...@linux.intel.com>

Best regards,
baolu

---
  drivers/iommu/intel/dmar.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c
index 2d70d56d8e0d..404b40af31cb 100644
--- a/drivers/iommu/intel/dmar.c
+++ b/drivers/iommu/intel/dmar.c
@@ -1136,7 +1136,7 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd)

static void free_iommu(struct intel_iommu *iommu)

  {
-       if (intel_iommu_enabled && iommu->iommu.ops) {
+       if (intel_iommu_enabled && !iommu->drhd->ignored) {
                iommu_device_unregister(&iommu->iommu);
                iommu_device_sysfs_remove(&iommu->iommu);
        }