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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 BAB5EC432C0 for ; Mon, 25 Nov 2019 13:47:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E3572082F for ; Mon, 25 Nov 2019 13:47:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574689623; bh=lMUZda1ivJX7Qdvty4z9vVwl6A7lYcjX1VND1/At+YI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=b5y4elk64KuezPDaW6ULPP7RbK2ql8tXaMqFdGfM5VzS5jI+LtmkxEObbI8Vxoj9b xBh0MtB6QwmBS2qlxL5ljpjfoMTNCq30O1rp3KNziDMzfroNbigUHU290uhMznDwWC Hp5EQun7wq41OFckvHPh9tLiieurtXCWl4Qs2goI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727793AbfKYNrD (ORCPT ); Mon, 25 Nov 2019 08:47:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:56334 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727462AbfKYNrC (ORCPT ); Mon, 25 Nov 2019 08:47:02 -0500 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E8CCD207FD; Mon, 25 Nov 2019 13:47:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574689622; bh=lMUZda1ivJX7Qdvty4z9vVwl6A7lYcjX1VND1/At+YI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=D9JCbT1o8Udg7sBwLtRWRebLzz95h4dxV1kG9QAhCJrTR5Na8YNKeCC58gauZxvuE Zjve2guKU+8S3mRjc9hraiVTg/IVvLr3PFUdNCH5tkvSJ9P+WXwyyVdlR7gUhyrpIx pv3iQma1i2x0thedqHMDSXh+dsS5Q80EVx7Os5Ro= Date: Mon, 25 Nov 2019 08:47:00 -0500 From: Sasha Levin To: Lee Jones Cc: gregkh@google.com, stable@vger.kernel.org Subject: Re: [PATCH 4.9 3/8] arm64: fix for bad_mode() handler to always result in panic Message-ID: <20191125134700.GA5861@sasha-vm> References: <20191122105253.11375-1-lee.jones@linaro.org> <20191122105253.11375-3-lee.jones@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20191122105253.11375-3-lee.jones@linaro.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, Nov 22, 2019 at 10:52:48AM +0000, Lee Jones wrote: >From: Hari Vyas > >[ Upstream commit e4ba15debcfd27f60d43da940a58108783bff2a6 ] > >The bad_mode() handler is called if we encounter an uunknown exception, >with the expectation that the subsequent call to panic() will halt the >system. Unfortunately, if the exception calling bad_mode() is taken from >EL0, then the call to die() can end up killing the current user task and >calling schedule() instead of falling through to panic(). > >Remove the die() call altogether, since we really want to bring down the >machine in this "impossible" case. Should this be in newer LTS kernels too? I don't see it in 4.14. We can't take anything into older kernels if it's not in newer ones - we don't want to break users who update their kernels. -- Thanks, Sasha