From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id 094576007E1 for ; Tue, 5 Jan 2010 11:12:12 -0500 (EST) Date: Tue, 5 Jan 2010 08:10:21 -0800 (PST) From: Linus Torvalds Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() In-Reply-To: <20100105154047.GA18217@ZenIV.linux.org.uk> Message-ID: References: <20100104182429.833180340@chello.nl> <20100104182813.753545361@chello.nl> <20100105092559.1de8b613.kamezawa.hiroyu@jp.fujitsu.com> <1262681834.2400.31.camel@laptop> <20100105154047.GA18217@ZenIV.linux.org.uk> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Al Viro Cc: Peter Zijlstra , KAMEZAWA Hiroyuki , "Paul E. McKenney" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "minchan.kim@gmail.com" , cl@linux-foundation.org, "hugh.dickins" , Nick Piggin , Ingo Molnar List-ID: On Tue, 5 Jan 2010, Al Viro wrote: > > - a bunch of fs operations done from RCU callbacks. Including severely > blocking ones. Yeah, you're right (and Peter also pointed out the might_sleep). That is likely to be the really fundamental issue. You _can_ handle it (make the RCU callback just schedule the work instead of doing it directly), but it does sound really nasty. I suspect we should explore just about any other approach over this one. Linus -- 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