From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751547AbaKIUUt (ORCPT ); Sun, 9 Nov 2014 15:20:49 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:58098 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751095AbaKIUUs (ORCPT ); Sun, 9 Nov 2014 15:20:48 -0500 Date: Sun, 9 Nov 2014 12:19:22 -0800 From: Greg KH To: Seth Jennings Cc: Josh Poimboeuf , Jiri Kosina , Vojtech Pavlik , Steven Rostedt , live-patching@vger.kernel.org, kpatch@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] kernel: add TAINT_LIVEPATCH Message-ID: <20141109201922.GB21349@kroah.com> References: <1415284748-14648-1-git-send-email-sjenning@redhat.com> <1415284748-14648-2-git-send-email-sjenning@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1415284748-14648-2-git-send-email-sjenning@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 06, 2014 at 08:39:07AM -0600, Seth Jennings wrote: > This adds a new taint flag to indicate when the kernel or a kernel > module has been live patched. This will provide a clean indication in > bug reports that live patching was used. > > Additionally, if the crash occurs in a live patched function, the live > patch module will appear beside the patched function in the backtrace. > > Signed-off-by: Seth Jennings > --- > Documentation/oops-tracing.txt | 2 ++ > Documentation/sysctl/kernel.txt | 1 + > include/linux/kernel.h | 1 + > kernel/panic.c | 2 ++ > 4 files changed, 6 insertions(+) > > diff --git a/Documentation/oops-tracing.txt b/Documentation/oops-tracing.txt > index beefb9f..f3ac05c 100644 > --- a/Documentation/oops-tracing.txt > +++ b/Documentation/oops-tracing.txt > @@ -270,6 +270,8 @@ characters, each representing a particular tainted value. > > 15: 'L' if a soft lockup has previously occurred on the system. > > + 16: 'K' if the kernel has been live patched. > + > The primary reason for the 'Tainted: ' string is to tell kernel > debuggers if this is a clean kernel or if anything unusual has > occurred. Tainting is permanent: even if an offending module is > diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt > index d7fc4ab..085f73b 100644 > --- a/Documentation/sysctl/kernel.txt > +++ b/Documentation/sysctl/kernel.txt > @@ -831,6 +831,7 @@ can be ORed together: > 8192 - An unsigned module has been loaded in a kernel supporting module > signature. > 16384 - A soft lockup has previously occurred on the system. > +32768 - The kernel has been live patched. > > ============================================================== > > diff --git a/include/linux/kernel.h b/include/linux/kernel.h > index 446d76a..a6aa2df 100644 > --- a/include/linux/kernel.h > +++ b/include/linux/kernel.h > @@ -473,6 +473,7 @@ extern enum system_states { > #define TAINT_OOT_MODULE 12 > #define TAINT_UNSIGNED_MODULE 13 > #define TAINT_SOFTLOCKUP 14 > +#define TAINT_LIVEPATCH 15 > > extern const char hex_asc[]; > #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] Note, this conflicts with a taint value that others are proposing for something else, so be aware you might run into problems when you hit linux-next. thanks, greg k-h