Re: [PATCH v1 33/36] mm/gup: drop nth_page() usage in unpin_user_page_range_dirty_lock()
David Hildenbrand <[email protected]>
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| Message-ID | <[email protected]> |
On 28.08.25 20:09, Lorenzo Stoakes wrote: > On Thu, Aug 28, 2025 at 12:01:37AM +0200, David Hildenbrand wrote: >> There is the concern that unpin_user_page_range_dirty_lock() might do >> some weird merging of PFN ranges -- either now or in the future -- such >> that PFN range is contiguous but the page range might not be. >> >> Let's sanity-check for that and drop the nth_page() usage. >> >> Signed-off-by: David Hildenbrand <[email protected]> > > Seems one user uses SG and the other is IOMMU and in each instance you'd > expect physical contiguity (maybe Jason G. or somebody else more familiar > with these uses can also chime in). Right, and I added the sanity-check so we can identify and fix any such wrong merging of ranges. Thanks! -- Cheers David / dhildenb