Re: [PATH v4 0/3] iommu/vt-d: debugfs: Enhancements to IOMMU debugfs

[Baolu Lu]

On 10/11/23 4:39 PM, Jingqi Liu wrote:
> The original debugfs only dumps all IOMMU page tables without pasid 
> supported. It traverses all devices on the pci bus, then dumps all page 
> tables based on device domains. This traversal is from software 
> perspective. This series dumps page tables whose mappings are created 
> and destroyed by the iommu_map/unmap() interfaces, by traversing root 
> tables, context tables, pasid directories and pasid tables from hardware 
> perspective. It supports dumping a specified page table in legacy mode 
> or scalable mode with or without a specified pasid. It adds a debugfs 
> directory per pair of {device, pasid} when attaching device with pasid, 
> i.e. /sys/kernel/debug/iommu/intel/<device source id>/<pasid>. And 
> create a debugfs file in the directory for users to dump the page table 
> corresponding to {device, pasid}. e.g. 
> /sys/kernel/debug/iommu/intel/0000:00:02.0/1/domain_translation_struct. 
> For the default domain without pasid, it creates a debugfs file in the 
> debugfs device directory for users to dump its page table. e.g. 
> /sys/kernel/debug/iommu/intel/0000:00:02.0/domain_translation_struct. 
> Remove the corresponding debugfs directory and file when detaching or 
> releasing a device. For legacy mode, according to bus number and DEVFN, 
> traverse the root table and context table to get the pointer of page 
> table in the context table entry, then dump the specified page table. 
> For scalable mode, according to bus number, DEVFN and pasid, traverse 
> the root table, context table, pasid directory and pasid table to get 
> the pointer of page table in the pasid table entry, then dump the 
> specified page table. Examples are as follows: 1) Dump the page table of 
> device "0000:00:01.0" that only supports legacy mode. $ sudo cat 
> /sys/kernel/debug/iommu/intel/0000:00:01.0/domain_translation_struct 2) 
> Dump the page table of device "0000:00:02.0" with PASID "1" that 
> supports scalable mode. $ sudo cat 
> /sys/kernel/debug/iommu/intel/0000:00:0a.0/1/domain_translation_struct

This series doesn't apply to v6.6-rc5. Can you please rebase and send a
new version?

Best regards,
baolu