On Thu, 15 Jan 2015, Andrew Morton wrote: > And perhaps some explanation here as to why virt_to_head_page() can > safely use compound_head_fast(). There's an assumption here that > nobody will be dismantling the compound page while virt_to_head_page() > is in progress, yes? And this assumption also holds for the calling > code, because otherwise the virt_to_head_page() return value is kinda > meaningless. I think this assumption is pretty natural to make. A coupound_head that works well while dismantling a compound page should be marked specially and Joonsoo's definition should be the standard. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>