From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 4 Feb 2004 20:54:35 +0000 (GMT) From: Hugh Dickins Subject: Re: [PATCH 0/5] mm improvements In-Reply-To: <20040204103307.7a288ce3.akpm@osdl.org> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Nikita@Namesys.COM, piggin@cyberone.com.au, linux-mm@kvack.org List-ID: On Wed, 4 Feb 2004, Andrew Morton wrote: > Hugh Dickins wrote: > > > > Sorry, that BUG_ON is there for very good reason. It's no disgrace > > that your testing didn't notice the effect of passing a mapped page > > down to shmem_writepage, but it is a serious breakage of tmpfs. > > hm. Can't I force writepage-of-a-mapped-page with msync()? I hope not, __filemap_fdatawrite still starts off with: if (mapping->backing_dev_info->memory_backed) return 0; Once upon a time you did have vmscan.c calling ->writepages, rather the effect that Nikita is trying for. It was that writepages which led me to insert the BUG_ON and give tmpfs a dummy writepages. Later on you dropped the ->writepages from vmscan.c: do you remember why? would be useful info for Nikita. Hugh -- 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: aart@kvack.org