From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sat, 6 May 2000 15:15:44 +0200 (CEST) From: Andrea Arcangeli Subject: Re: Updates to /bin/bash In-Reply-To: <14610.29880.728540.947675@charged.uio.no> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Trond Myklebust Cc: Matthew Vanecek , linux-kernel@vger.rutgers.edu, linux-mm@kvack.org List-ID: On Fri, 5 May 2000, Trond Myklebust wrote: >NO. This behaviour is exactly what Andreas patch would break. New My patch won't hurt the bash update as far I can tell. In clean 2.2.15 and clean 2.3.99-pre7-pre6 you don't unmap the page from the ptes, so if nfs doesn't keep to do the pageins from the inode pointed by the nfsfilehandle, then you'll get a mixture anyway even if you drop the mapped pages from the cache (and nfs probably can't keep do to the pageins from the old file if somebody replaced bash on the real fs but in the worst case nfs should notice that and it should abort the `bash` execution and to never do the silent mixture). New executed bash are not an issue since they will get a new inode present on the server and so they won't risk to do the mixture. All above thoughts assumes the admin correctly uses remove(2) to upgrade bash (otherwise the mixture would happen also on top of ext2). About the stability issue I looked some more and maybe the VM is not subject to stability issues by dropping a mapped cache-page from the cache (however the thing keeps to look not robust to me). Everything depends on the page->index that have to be not clobbered after dropping the page from the cache (while page->index is supposed to have a meaning only on pagecache or swapcache). Andrea -- 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.eu.org/Linux-MM/