Re: [PATCH 1/1] iommu/vt-d: Avoid WARNING in sva unbind path

[Baolu Lu <baolu.lu@linux.intel.com>]

On 5/19/26 13:29, Lu Baolu wrote:
> The Intel IOMMU driver allows SVA on devices even if they do not support
> PCI/PRI. Commit 39c20c4e83b9 ("iommu/vt-d: Only handle IOPF for SVA when
> PRI is supported") modified the SVA bind path to allow this configuration
> by skipping IOPF enablement when PRI is missing. However, it failed to
> update the unbind path.
> 
> This creates an imbalance: the unbind path attempts to disable IOPF for
> a device that never had it enabled, triggering a WARNING in
> intel_iommu_disable_iopf():
> 
>   WARNING: drivers/iommu/intel/iommu.c:3475 at intel_iommu_disable_iopf+0x4f/0x90d
>   Call Trace:
>    <TASK>
>    blocking_domain_set_dev_pasid+0x50/0x70
>    iommu_detach_device_pasid+0x89/0xc0
>    iommu_sva_unbind_device+0x73/0x150
>    xe_vm_close_and_put+0x4d2/0x1200 [xe]
> 
> Fix this by bypassing IOPF operations for SVA domains on non-PRI hardware
> in both the bind and unbind paths.
> 
> Fixes: 39c20c4e83b9 ("iommu/vt-d: Only handle IOPF for SVA when PRI is supported")
> Cc:stable@vger.kernel.org
> Reported-by: Nareshkumar Gollakoti<naresh.kumar.g@intel.com>
> Signed-off-by: Lu Baolu<baolu.lu@linux.intel.com>
> ---
>   drivers/iommu/intel/iommu.h | 11 +++++++++++
>   drivers/iommu/intel/svm.c   | 12 ++++--------
>   2 files changed, 15 insertions(+), 8 deletions(-)

Queued for linux-next.