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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,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 31C0EC432C3 for ; Mon, 25 Nov 2019 14:44:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0B24F2084D for ; Mon, 25 Nov 2019 14:44:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="uAnJ8STu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728071AbfKYOos (ORCPT ); Mon, 25 Nov 2019 09:44:48 -0500 Received: from mail-wr1-f65.google.com ([209.85.221.65]:34580 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728040AbfKYOos (ORCPT ); Mon, 25 Nov 2019 09:44:48 -0500 Received: by mail-wr1-f65.google.com with SMTP id t2so18374777wrr.1 for ; Mon, 25 Nov 2019 06:44:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=khe/dfoPMKhaf3PxkPvOwwNcBhD8fASQAgj+tzlS8W4=; b=uAnJ8STu7tmpUP8ErFcyZT20GB0M0Iyup3frEtXBREMYIkRJLNqF+TjzUCOsX+MXSA SAJd6ttTnvC/onz/wl5ZSsdjzqJlV7lBYzvO6Go+72pAJjzfvstpuk+qiLO2xiqLzXpV xJsv6KLe8Dibfibf0SrRzFJCDAq8CySNv8RQgWlCVHrIlU0cWguTOtGCKLbg9Qth+nMO KYSFDPSvZsHbgtgPqVQz0eZX9k/PoPk5QYx+vJkK4TcRpj4AAf8UGG4y3LO7fCnZ2aiW +4h2zspExVbGenx8ylmeHgNOhRFEYtVJpo2unSrra86MG3gLLLSG3KBC6whs94pdsb03 +EXQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=khe/dfoPMKhaf3PxkPvOwwNcBhD8fASQAgj+tzlS8W4=; b=b0VZwv04jRrqYZ684MTw3839FHKiYHkgswI1HKyrDbj3x2WNWDea5w6ui8vqSP24jm mHom+9Zr5YBFxmAAl8HhKyBFc2VZ09kEcnj1AWCHy/vDfuIuWGsMyLocNGBRfTwgczRZ nGquQU3E5Los/cdtbhUs5QkxPiA1zyBfQu1CbRkJ5nlNWwMAPqIx3LfWoaS3Dogul/g8 H53xGrbvsVxtXfkz9/NL5Ld6h0t6UbCTHeIOsTYL1IjGd500MQjIcalu8f5/v5rMuzbJ 7ed2doyZn9lfXXbsp+u2uM60YKsPNczMvq1fKPSb3FZP/HSX5+SNJQZvHSzpwsqGSzvG wNgg== X-Gm-Message-State: APjAAAUOiVc3dfljEmtoXQtw2LRIfv+bG2ZwmXNSVtcR6NV0sgrUcWJ/ rtpMA1+OspDoxhHmYEYqNmTOwX55Njc= X-Google-Smtp-Source: APXvYqx0qYWa8ijHQreAb3u3sNbKEtPlsdV5upCoDbByr71Xe5JZmESaaH+7WM1exylROvZ3cuCFHw== X-Received: by 2002:adf:f50b:: with SMTP id q11mr32114387wro.343.1574693084731; Mon, 25 Nov 2019 06:44:44 -0800 (PST) Received: from dell ([95.149.164.72]) by smtp.gmail.com with ESMTPSA id s11sm11060259wrr.43.2019.11.25.06.44.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Nov 2019 06:44:43 -0800 (PST) Date: Mon, 25 Nov 2019 14:44:29 +0000 From: Lee Jones To: Sasha Levin 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: <20191125144429.GF3296@dell> References: <20191122105253.11375-1-lee.jones@linaro.org> <20191122105253.11375-3-lee.jones@linaro.org> <20191125134700.GA5861@sasha-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20191125134700.GA5861@sasha-vm> 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 Mon, 25 Nov 2019, Sasha Levin wrote: > 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. Only; 3.18, 4.4, 4.9 and 5.3 were studied. I can look at others if it helps. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog