Re: [PATCH v2 11/20] amd_iommu: Use iova_tree records to determine large page size on UNMAP

[Alejandro Jimenez]

On 6/11/25 4:29 AM, Sairaj Kodilkar wrote:


On 5/2/2025 7:45 AM, Alejandro Jimenez wrote:

  next:
-        iova = iova_next;
+        iova = (iova & ~(pagesize - 1)) + pagesize;

Hi Alejandro,
While experimenting with iommu.forcedac=1, I found that above line 
causes unsigned integer overflow for 64 bit IOVAs. This results in an 
infinite loop.

Please add a overflow check here.


Good catch. Reproduced it and tested the fix; will include it in next 
revision.

Thank you,
Alejandro

Thanks
Sairaj Kodilkar