From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [patch 13/26] Xen-paravirt_ops: Consistently wrap paravirt ops callsites to make them patchable Date: Tue, 20 Mar 2007 09:52:42 -0700 (PDT) Message-ID: References: <20070319.120854.30182994.davem@davemloft.net> <20070319.204712.118947830.davem@davemloft.net> <200703201428.50564.ak@suse.de> <20070320174159.GA4286@bingen.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20070320174159.GA4286@bingen.suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Andi Kleen Cc: xen-devel@lists.xensource.com, netdev@vger.kernel.org, mingo@elte.hu, linux-kernel@vger.kernel.org, jbeulich@novell.com, virtualization@lists.linux-foundation.org, chrisw@sous-sol.org, virtualization@lists.osdl.org, "Eric W. Biederman" , anthony@codemonkey.ws, akpm@linux-foundation.org, David Miller List-Id: virtualization@lists.linuxfoundation.org On Tue, 20 Mar 2007, Andi Kleen wrote: > = > No, me and Jan fixed all reported bugs as far as I know. No you did not. You didn't fix the ones I reported. Which is why it got = removed, and will not get added back until there is another maintainer. The ones I reported were all about trusting the stack contents implicitly, = and assuming that the unwind info was there and valid. Using things like = "__get_user()" didn't fix it, because if a WARN_ON() happened while we = held the mm semaphore and the unwind info was bogus, it would take a = page-fault and deadlock. Those kinds of things are not acceptable for debugging output. If I cannot = use WARN_ON() because I hold the MM lock and I'm afraid there might be = kernel corruption, then something is *wrong*! And I told you guys this. Over *months*. And you ignored me. You told me = everything was fine. Each time, somebody else ended up reporting a hang = where the unwinder was at fault. And since I couldn't trust the = maintainers to fix it, removing the broken feature that only caused more = problems than it fixed was the only option. And you clearly *still* haven't accepted the fact that the code was buggy. = Does anybody wonder why I wouldn't merge it back? Linus