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=-3.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 34012C43381 for ; Sun, 10 Mar 2019 10:04:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 04CBC207E0 for ; Sun, 10 Mar 2019 10:04:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726438AbfCJKEy (ORCPT ); Sun, 10 Mar 2019 06:04:54 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:34625 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726000AbfCJKEy (ORCPT ); Sun, 10 Mar 2019 06:04:54 -0400 Received: by mail-pg1-f194.google.com with SMTP id u65so1722371pgc.1 for ; Sun, 10 Mar 2019 03:04:53 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=LV3A1K28ZzdlaXBJ+m4jDlY+1loO1xTntknB7j9GNVc=; b=WtJdzWeexTPysHsyx3COQdBqDtjyPGdHvrVGHOY/9d3vWxGk6CwqlMzy+XIj+N4XUq 6dWLvQMWvB4ZqEg4dk4uSmoLuTXHei8F1Y7g8a2zGpf8f/kkNKbla0KkonuA/DMmZ2c7 VkETKqecY7ZCZXWxHVmthjfl7rdB479uB5yGr48UutPJaLXVTT2P63U9XGjMIeqWSQdv 2UkefIWLc6olrIPSZh6TZKx4Gg01oqL2/y8LhZVkJyTKKl1yRfressSF/qm2NXZTKS6X g7jdSNFvR07Pd7n4/qYi+IPGxN0MoHtYnEMT6fiWf9TywEXzXS0tWwYhE7ZCMspHAYAb HmmA== X-Gm-Message-State: APjAAAUZxSm4W9+58ADSJGm/X+h34tpmADISFDyEecgMr+3a0SY3VYnf EDYO/DEKCw24rqX8IZ3PkPmvEBJu6c8= X-Google-Smtp-Source: APXvYqwvqV+s+YSa4RrgVVU1zmYLlcj68VnkbN9gYn1E1+qoEavuXS/+Gku4N9ALNKZJO+0AiddaFQ== X-Received: by 2002:a63:ed45:: with SMTP id m5mr3439137pgk.265.1552212292391; Sun, 10 Mar 2019 03:04:52 -0700 (PDT) Received: from localhost ([106.215.118.61]) by smtp.gmail.com with ESMTPSA id o2sm7496739pgq.29.2019.03.10.03.04.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 10 Mar 2019 03:04:51 -0700 (PDT) From: Bhupesh Sharma To: linux-kernel@vger.kernel.org Cc: bhsharma@redhat.com, bhupesh.linux@gmail.com, Mark Rutland , James Morse , Will Deacon , Boris Petkov , Ingo Molnar , Thomas Gleixner , Michael Ellerman , Paul Mackerras , Benjamin Herrenschmidt , Dave Anderson , Kazuhito Hagio , x86@kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, kexec@lists.infradead.org Subject: [PATCH v2 0/2] Append new variables to vmcoreinfo (PTRS_PER_PGD for arm64 and MAX_PHYSMEM_BITS for all archs) Date: Sun, 10 Mar 2019 15:34:00 +0530 Message-Id: <1552212242-9479-1-git-send-email-bhsharma@redhat.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Changes since v1: ---------------- - v1 was sent out as a single patch which can be seen here: http://lists.infradead.org/pipermail/kexec/2019-February/022411.html - v2 breaks the single patch into two independent patches: [PATCH 1/2] appends 'PTRS_PER_PGD' to vmcoreinfo for arm64 arch, whereas [PATCH 2/2] appends 'MAX_PHYSMEM_BITS' to vmcoreinfo in core kernel code (all archs) This patchset primarily fixes the regression reported in user-space utilities like 'makedumpfile' and 'crash-utility' on arm64 architecture with the availability of 52-bit address space feature in underlying kernel. These regressions have been reported both on CPUs which don't support ARMv8.2 extensions (i.e. LVA, LPA) and are running newer kernels and also on prototype platforms (like ARMv8 FVP simulator model) which support ARMv8.2 extensions and are running newer kernels. The reason for these regressions is that right now user-space tools have no direct access to these values (since these are not exported from the kernel) and hence need to rely on a best-guess method of determining value of 'PTRS_PER_PGD' and 'MAX_PHYSMEM_BITS' supported by underlying kernel. Exporting these values via vmcoreinfo will help user-land in such cases. In addition, as per suggestion from makedumpfile maintainer (Kazu) during v1 review, it makes more sense to append 'MAX_PHYSMEM_BITS' to vmcoreinfo in the core code itself rather than in arm64 arch-specific code, so that the user-space code for other archs can also benefit from this addition to the vmcoreinfo and use it as a standard way of determining 'SECTIONS_SHIFT' value in user-land. Cc: Mark Rutland Cc: James Morse Cc: Will Deacon Cc: Boris Petkov Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Michael Ellerman Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: Dave Anderson Cc: Kazuhito Hagio Cc: x86@kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: kexec@lists.infradead.org Bhupesh Sharma (2): arm64, vmcoreinfo : Append 'PTRS_PER_PGD' to vmcoreinfo crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfo arch/arm64/kernel/crash_core.c | 1 + kernel/crash_core.c | 1 + 2 files changed, 2 insertions(+) -- 2.7.4