On Wed, May 26, 2021 at 01:12:38PM -0700, Yang Shi wrote: > When debugging the bug reported by Wang Yugui [1], try_to_unmap() may > fail, but the first VM_BUG_ON_PAGE() just checks page_mapcount() however > it may miss the failure when head page is unmapped but other subpage is > mapped. Then the second DEBUG_VM BUG() that check total mapcount would > catch it. This may incur some confusion. And this is not a fatal issue, > so consolidate the two DEBUG_VM checks into one VM_WARN_ON_ONCE_PAGE(). > > [1] https://lore.kernel.org/linux-mm/20210412180659.B9E3.409509F4@xxxxxxxxxxxx/ > > Reviewed-by: Zi Yan <ziy@xxxxxxxxxx> > Signed-off-by: Yang Shi <shy828301@xxxxxxxxx> For both patches: Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> -- Kirill A. Shutemov
