Hillf Danton wrote: > On Sun, May 12, 2013 at 9:23 AM, Kirill A. Shutemov > <kirill.shutemov@xxxxxxxxxxxxxxx> wrote: > > page = vmf.page; > > + > > + /* > > + * If we asked for huge page we expect to get it or VM_FAULT_FALLBACK. > > + * If we don't ask for huge page it must be splitted in ->fault(). > > + */ > > + BUG_ON(PageTransHuge(page) != thp); > > + > Based on the log message in 34/39( > If the area of page cache required to create huge is empty, we create a > new huge page and return it.), the above trap looks bogus. The statement in 34/39 is true for (flags & FAULT_FLAG_TRANSHUGE). For !(flags & FAULT_FLAG_TRANSHUGE) huge page must be split in ->fault. The BUG_ON() above is shortcut for two checks: if (thp) BUG_ON(!PageTransHuge(page)); if (!thp) BUG_ON(PageTransHuge(page)); -- Kirill A. Shutemov -- 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>