Re: [PATCH v2 5/5] PCI/ATS: Mandate checking pci_ats_supported() before pci_prepare_ats()

[Vasant Hegde]

On 8/14/2026 7:26 AM, Pranjal Shrivastava wrote:
> Currently, pci_prepare_ats() internally calls pci_ats_supported() and
> returns -EINVAL if the device does not support ATS. While this provides
> a silent safety check, it conflates support detection with configuration.
> 
> Update pci_prepare_ats() to wrap the internal pci_ats_supported check in
> a WARN_ON(). This mandates all callers to call pci_prepare_ats() only if
> the function supports ATS.
> 
> Update the function documentation to mention that callers must verify
> ATS support (via pci_ats_supported()) before calling pci_prepare_ats().
> 
> Suggested-by: Baolu Lu <baolu.lu@xxxxxxxxxxxxxxx>
> Reviewed-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Pranjal Shrivastava <praan@xxxxxxxxxx>

Reviewed-by: Vasant Hegde <vasant.hegde@xxxxxxx>

-Vasant