On 11/10/22 16:51, Alistair Popple wrote:
migrate_vma->cpages originally contained a count of the number of pages migrating including non-present pages which can be poluated
"populated"
directly on the target. Commit 241f68859656 ("mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page()") inadvertantly changed this to contain just the number of pages that were unmapped. Usage of migrate_vma->cpages isn't documented, but most drivers use it to see if all the requested addresses can be migrated so restore the original behaviour. Fixes: 241f68859656 ("mm/migrate_device.c: refactor migrate_vma and migrate_deivce_coherent_page()") Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx> Reported-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
You can add Reviewed-by: Ralph Campbell <rcampbell@xxxxxxxxxx> Thanks!