Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262184AbVAIBjA (ORCPT ); Sat, 8 Jan 2005 20:39:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262185AbVAIBjA (ORCPT ); Sat, 8 Jan 2005 20:39:00 -0500 Received: from fw.osdl.org ([65.172.181.6]:17025 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262184AbVAIBi5 (ORCPT ); Sat, 8 Jan 2005 20:38:57 -0500 Date: Sat, 8 Jan 2005 17:38:50 -0800 (PST) From: Linus Torvalds To: Marcelo Tosatti cc: Alan Cox , Lukasz Trabinski , Linux Kernel Mailing List Subject: Re: uselib() & 2.6.X? In-Reply-To: <20050108182841.GD2701@logos.cnet> Message-ID: References: <20050107170712.GK29176@logos.cnet> <1105136446.7628.11.camel@localhost.localdomain> <20050107221255.GA8749@logos.cnet> <20050108182841.GD2701@logos.cnet> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1367 Lines: 31 On Sat, 8 Jan 2005, Marcelo Tosatti wrote: > > > No, I'd just fix them up. > > What do you mean by "fix them up" ? With your minimal fix the other do_brk() callers > do not have the lock, you dont mean "fix" by grabbing the lock? I'm saying that if we decide to do the debugging warning (and I think everybody is agreeing that we should), then we _will_ fix it by just grabbing the lock in all the paths. That's what we already did with do_mmap(), after all. I suspect it's not strictly needed, but as Alan has said, even though nothing else can chaneg the vma's at the same time, it's the right thing to do to keep /proc reads happy (which _can_ happen) anyway. And more importantly, invariants are nice - to the point where it's good to follow the rules even if it might not be strictly necessary. I just wanted to keep these two issues separate. I think it's one thing to fix a known bug, and another thing to add some debug infrastructure to make sure that it doesn't happen in the future. So I think the WARN_ON() + adding of extra locking is a separate stage from fixing the known problem. Linus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/