From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 19 Jul 2007 22:32:08 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [BUGFIX]{PATCH] flush icache on ia64 take2 Message-Id: <20070719223208.87383731.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20070719220118.73f40346.kamezawa.hiroyu@jp.fujitsu.com> References: <20070706112901.16bb5f8a.kamezawa.hiroyu@jp.fujitsu.com> <20070719155632.7dbfb110.kamezawa.hiroyu@jp.fujitsu.com> <469F5372.7010703@bull.net> <20070719220118.73f40346.kamezawa.hiroyu@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: KAMEZAWA Hiroyuki Cc: Zoltan.Menyhart@bull.net, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, tony.luck@intel.com, nickpiggin@yahoo.com.au, mike@stroyan.net, dmosberger@gmail.com, y-goto@jp.fujitsu.com List-ID: On Thu, 19 Jul 2007 22:01:18 +0900 KAMEZAWA Hiroyuki wrote: > On Thu, 19 Jul 2007 14:05:06 +0200 > Zoltan Menyhart wrote: > > > KAMEZAWA Hiroyuki wrote: > > > > > Then, what should I do more for fixing this SIGILL problem ? > > > > > > -Kame > > > > I can think of a relatively cheap solution: > > > Maybe I should take performance numbers with the patch. > > But is it too costly that flushing icache page only if a page is newly > installed into the system (PG_arch1) && it is mapped as executable ? > > I don't want to leak this (stupid) corner case to the file system layer. > Hmm...can't we do clever flushing (like your idea) in VM layer ? > A bit new idea. How about this ? == - Set PG_arch_1 if "icache is *not* coherent" - make flush_dcache_page() to be empty func. - For Montecito, add kmap_atomic(). This function just set PG_arch1. Then, "the page which is copied by the kernel" is marked as "not icache coherent page" - icache_flush_page() just flushes a page which has PG_arch_1. - Anonymous page is always has PG_arch_1. Tkae care of Copy-On-Write. == looks easy ? -Kame -- 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