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=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 68051C43387 for ; Sat, 15 Dec 2018 01:53:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 78F44206C0 for ; Sat, 15 Dec 2018 01:53:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lca.pw header.i=@lca.pw header.b="O4lVycTG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729275AbeLOBxv (ORCPT ); Fri, 14 Dec 2018 20:53:51 -0500 Received: from mail-qt1-f195.google.com ([209.85.160.195]:33760 "EHLO mail-qt1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726609AbeLOBxv (ORCPT ); Fri, 14 Dec 2018 20:53:51 -0500 Received: by mail-qt1-f195.google.com with SMTP id l11so8399142qtp.0 for ; Fri, 14 Dec 2018 17:53:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lca.pw; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=5fLN/04WiJj7PmtbOE2x1OBSl08T5I2Ie0RV1VKgEUE=; b=O4lVycTGef9WbcDjIsKfE3bJhLwq67YI4yLwUOWamvak6Uiw8KPHpqQ+dhDX/c3J9R Nqb2iriXc3X/rmKaP9ORc4a+ixfnc9Z1V0RLEvJmWJDO2WpB83WPNHPTK5kzL59ugbnK aUWi73JGF9hYhNlR9osQuDe7aduYqIW0zBTHvxOcMGaaTopr7eCZ1B3vNjc/VmG5dhZn ZXtDtAYCLN4luInbAMA8axm3ounsd2CEXjPZ4l/JbKMXECpxPVvqYrueln3WZ2kwZ1TS 3+OJHQX6nXbGoGQSpG1RvBbGmqlPZVAHhdYy+mdF5kRM3SFgm0LVF9jvbrWg5Dogh/Yl nF1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=5fLN/04WiJj7PmtbOE2x1OBSl08T5I2Ie0RV1VKgEUE=; b=EAiHFRFyCOizCf0En09+1JiqT1xAW7svCgtF8/E8Mn6OVFZJIfpOzCEUEpUXt7rVsC nnFlUD0VzSVNPI4HzAJd9ki3ooz9KveAD6B+wMlfj4WlWby0rLsbun3tSklM6oMJuINy BG0mPlayqQdKK3w+9VECJKKSTYTBzYwR2jCLi1WB+uDwkc+kBPhTkUonFk40NhvxQvzp lG6aCShf6VkworGJDetfpc7pXJI1X1SZmh4Jj64zoNkLZeiWvc+/usX2dv/6rmNwV6/S XYuyjTzKZYrSPBNCZ3rFwpGgJv6ohZoQGm5wNXldd1REwAJNuKawqNcUaDYrpxiUfYxL U9Zg== X-Gm-Message-State: AA+aEWa5pSf80q7pOBFCzgM6dPbmldHupFIV8rWZTcFKlBM9Pr4//sYR rcVyFSUXDraNy8Xkxe624bUlhTfTMsM= X-Google-Smtp-Source: AFSGD/VCujxlpKTzIYUw7Q8DIO29P5UGCS9zMFKfbPXpQ3hwDbOqLJsd90b5eSTwIWSVaEV0c/R2tQ== X-Received: by 2002:ac8:498c:: with SMTP id f12mr5147743qtq.130.1544838829975; Fri, 14 Dec 2018 17:53:49 -0800 (PST) Received: from ovpn-121-90.rdu2.redhat.com (pool-71-184-117-43.bstnma.fios.verizon.net. [71.184.117.43]) by smtp.gmail.com with ESMTPSA id j36sm4097194qtk.15.2018.12.14.17.53.49 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 14 Dec 2018 17:53:49 -0800 (PST) Subject: Re: [PATCH v2] arm64: invalidate TLB just before turning MMU on To: Ard Biesheuvel Cc: Catalin Marinas , Will Deacon , Marc Zyngier , James Morse , AKASHI Takahiro , linux-arm-kernel , Kexec Mailing List , Linux Kernel Mailing List References: <20181213052259.56352-1-cai@lca.pw> <20181214040819.58625-1-cai@lca.pw> From: Qian Cai Message-ID: Date: Fri, 14 Dec 2018 20:53:48 -0500 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.3.3 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/14/18 2:23 AM, Ard Biesheuvel wrote: > On Fri, 14 Dec 2018 at 05:08, Qian Cai wrote: >> Also tried to move the local TLB flush part around a bit inside >> __cpu_setup(), although it did complete kdump some times, it did trigger >> "Synchronous Exception" in EFI after a cold-reboot fairly often that >> seems no way to recover remotely without reinstalling the OS. > > This doesn't make any sense to me. If the system gets into a weird > state out of cold reboot, how could this code be the culprit? Please > check your firmware, and try to reproduce the issue on a system that > doesn't have such defects. > I'll continue investigating those "Synchronous Exception" although it is kind of hard due to I don't have any source code of the firmware to confirm it is buggy or not. I did manage to reproduce this kdump issue on around 5 of those server running a fairly recent version of the firmware (07/01/2018). I don't have access to other large CPU machines.