Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755751AbcDANew (ORCPT ); Fri, 1 Apr 2016 09:34:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:60418 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753517AbcDANeu (ORCPT ); Fri, 1 Apr 2016 09:34:50 -0400 Date: Fri, 1 Apr 2016 15:34:47 +0200 (CEST) From: Miroslav Benes To: Josh Poimboeuf cc: Jiri Kosina , Jessica Yu , linux-kernel@vger.kernel.org, live-patching@vger.kernel.org, Vojtech Pavlik Subject: Re: [RFC PATCH v1.9 00/14] livepatch: hybrid consistency model In-Reply-To: Message-ID: References: User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 875 Lines: 21 > - actually test it I did slightly and it partially worked and partially it did not. When I applied sample livepatch module, /proc/cmdline was patched and when I called 'cat /proc/cmdline' I got the correct livepatched message. So far so good. But the patching itself never finished because of many processes with unreliable stacks. It almost looked like every sleeping process was reported. I haven't debugged that yet. Second, I have a simple test case. Kthread which sleeps in to-be-patched function foo() for a while and then it sleeps somewhere else and that in a loop. After live patch application the kthread is reported to have unreliable stack and it is not migrated. The good thing is that also the function foo() from the old universe is called and thus the consistency model works. So I guess there is some problem in a stack checking... Miroslav