From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <48B5A4B0.9050308@goop.org> Date: Wed, 27 Aug 2008 12:02:08 -0700 From: Jeremy Fitzhardinge MIME-Version: 1.0 Subject: Definition of x86 _PAGE_SPECIAL and sharing _PAGE_UNUSED1 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Nick Piggin Cc: Ingo Molnar , Hugh Dickens , Linux Kernel Mailing List , Andrew Morton , Linux Memory Management List List-ID: _PAGE_SPECIAL is overloading _PAGE_UNUSED1. Does it really leave _PAGE_UNUSED1 available for other uses, or does it become an exclusive user of that flag. Under what circumstances can they be shared? arch/x86/mm/pageattr-test.c is now using _PAGE_UNUSED1 as the flag used to make sure that huge pages are shattered properly (previously it used _PAGE_GLOBAL). Is that going to clash with _PAGE_SPECIAL? In other words, should we drop _PAGE_UNUSED1 altogether, or at least define how the its different users can coexist? Am I right in supposing that _PAGE_SPECIAL can only be set on user pages? (Also, "SPECIAL" is awfully generic. Was there really no more descriptive name for this?) J -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org