From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4256AC4724C for ; Thu, 7 May 2020 22:22:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1F7182082E for ; Thu, 7 May 2020 22:22:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="P0eiat9R" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727113AbgEGWWF (ORCPT ); Thu, 7 May 2020 18:22:05 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:54755 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726863AbgEGWWF (ORCPT ); Thu, 7 May 2020 18:22:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588890124; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=H1fE5P6+fvPAXaUqAeYEo8nNr2ZmJz9U6Sff/jvrkLc=; b=P0eiat9R3lzKpbyCjv7SppU5qAtFkFO7M6k+7MGNPid6ZNX231Nxyo5mBUXmD6hKJqTm2p 0gy7FUS0IzmtlK4KjUAR0EY6PSFqSfB7pMB2qo4+Jf3AyOj/uLaAnAtaKZb2sUz/IOI9DS PyHrRZy+Uv5DChPIAMduB85MHz4Mwso= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-196-hlU1JeMCM2mh6kooH-rKBg-1; Thu, 07 May 2020 18:15:13 -0400 X-MC-Unique: hlU1JeMCM2mh6kooH-rKBg-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D6808107ACCA; Thu, 7 May 2020 22:15:11 +0000 (UTC) Received: from optiplex-lnx (unknown [10.3.128.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 70153649B1; Thu, 7 May 2020 22:15:06 +0000 (UTC) Date: Thu, 7 May 2020 18:15:03 -0400 From: Rafael Aquini To: Qian Cai Cc: Andrew Morton , LKML , linux-doc@vger.kernel.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, dyoung@redhat.com, Baoquan He , Jonathan Corbet , Luis Chamberlain , Kees Cook Subject: Re: [PATCH] kernel: add panic_on_taint Message-ID: <20200507221503.GL205881@optiplex-lnx> References: <20200506222815.274570-1-aquini@redhat.com> <20200507204219.GJ205881@optiplex-lnx> <27AA744E-930A-492A-BE87-05A119FE1549@lca.pw> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <27AA744E-930A-492A-BE87-05A119FE1549@lca.pw> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, May 07, 2020 at 06:05:27PM -0400, Qian Cai wrote: > > > > On May 7, 2020, at 4:42 PM, Rafael Aquini wrote: > > > > On Wed, May 06, 2020 at 10:50:19PM -0400, Qian Cai wrote: > >> > >> > >>> On May 6, 2020, at 6:28 PM, Rafael Aquini wrote: > >>> > >>> Analogously to the introduction of panic_on_warn, this patch > >>> introduces a kernel option named panic_on_taint in order to > >>> provide a simple and generic way to stop execution and catch > >>> a coredump when the kernel gets tainted by any given taint flag. > >>> > >>> This is useful for debugging sessions as it avoids rebuilding > >>> the kernel to explicitly add calls to panic() or BUG() into > >>> code sites that introduce the taint flags of interest. > >>> Another, perhaps less frequent, use for this option would be > >>> as a mean for assuring a security policy (in paranoid mode) > >>> case where no single taint is allowed for the running system. > >> > >> Andrew, you can drop the patch below from -mm now because that one is now obsolete, > >> > >> mm-slub-add-panic_on_error-to-the-debug-facilities.patch > >> > > Please, don't drop it yet. I'll send a patch to get rid of the bits, > > once this one gets accepted, if it gets accepted. > > Why do you ever want that obsolete patch even show up in linux-next to potentailly waste other people/bots time to test it and develop things on top of it? > It's a reasonable and self-contained feature that we have a valid use for. I honestly fail to see it causing that amount of annoyance as you are suggesting here.