Re: [PATCH v3 3/5] drm/xe/bo: Add a bo remove callback

[Matthew Auld <matthew.auld@intel.com>]

On 24/03/2025 16:54, Thomas Hellström wrote:
> On device unbind, migrate exported bos, including pagemap bos to
> system. This allows importers to take proper action without
> disruption. In particular, SVM clients on remote devices may
> continue as if nothing happened, and can chose a different
> placement.
> 
> The evict_flags() placement is chosen in such a way that bos that
> aren't exported are purged.
> 
> For pinned bos, we unmap DMA, but their pages are not freed yet
> since we can't be 100% sure they are not accessed.
> 
> All pinned external bos (not just the VRAM ones) are put on the
> pinned.external list with this patch. But this only affects the
> xe_bo_pci_dev_remove_pinned() function since !VRAM bos are
> ignored by the suspend / resume functionality. As a follow-up we
> could look at removing the suspend / resume iteration over
> pinned external bos since we currently don't allow pinning
> external bos in VRAM, and other external bos don't need any
> special treatment at suspend / resume.
> 
> v2:
> - Address review comments. (Matthew Auld).
> v3:
> - Don't introduce an external_evicted list (Matthew Auld)
> - Add a discussion around suspend / resume behaviour to the
>    commit message.
> - Formatting fixes.
> 
> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>

Reviewed-by: Matthew Auld <matthew.auld@intel.com>