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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 45BDDC43381 for ; Tue, 12 Mar 2019 00:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1FB642084F for ; Tue, 12 Mar 2019 00:50:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726699AbfCLAu1 (ORCPT ); Mon, 11 Mar 2019 20:50:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49758 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726581AbfCLAuY (ORCPT ); Mon, 11 Mar 2019 20:50:24 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 96B88C070E0B; Tue, 12 Mar 2019 00:50:24 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-19.pek2.redhat.com [10.72.12.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 97E1A5C220; Tue, 12 Mar 2019 00:50:21 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de, kirill.shutemov@linux.intel.com, mingo@kernel.org, bp@alien8.de, hpa@zytor.com, dyoung@redhat.com, x86@kernel.org, Baoquan He Subject: [PATCH v2 3/3] x86/kdump/64: Change the upper limit of crashkernel reservation Date: Tue, 12 Mar 2019 08:50:04 +0800 Message-Id: <20190312005004.19182-4-bhe@redhat.com> In-Reply-To: <20190312005004.19182-1-bhe@redhat.com> References: <20190312005004.19182-1-bhe@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.31]); Tue, 12 Mar 2019 00:50:24 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Restrict kdump to only reserve crashkernel below 64TB. Since the kdump jumping may be from 5-level to 4-level, and the kdump kernel is put above 64TB in 5-level kernel, then the jumping will fail. And the crashkernel reservation is done during the 1st kernel bootup, there's no way to detect the paging mode of kdump kernel at that time. Hence change the upper limit of crashkernel reservation to 64TB on x86_64. Signed-off-by: Baoquan He --- arch/x86/kernel/setup.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 3d872a527cd9..d4d1366738a4 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -451,16 +451,26 @@ static void __init memblock_x86_reserve_range_setup_data(void) #define CRASH_ALIGN (16 << 20) /* - * Keep the crash kernel below this limit. On 32 bits earlier kernels - * would limit the kernel to the low 512 MiB due to mapping restrictions. - * On 64bit, old kexec-tools need to under 896MiB. + * Keep the crash kernel below this limit. + * + * On 32 bits earlier kernels would limit the kernel to the low + * 512 MiB due to mapping restrictions. + * + * On 64bit, old kexec-tools need to be under 896MiB. The later + * supports to put kernel above 4G, up to system RAM top. Here + * kdump kernel need be restricted to be under 64TB, which is + * the upper limit of system RAM in 4-level paing mode. Since + * the kdump jumping could be from 5-level to 4-level, the jumping + * will fail if kernel is put above 64TB, and there's no way to + * detect the paging mode of the kernel which will be loaded for + * dumping during the 1st kernel bootup. */ #ifdef CONFIG_X86_32 # define CRASH_ADDR_LOW_MAX (512 << 20) # define CRASH_ADDR_HIGH_MAX (512 << 20) #else # define CRASH_ADDR_LOW_MAX (896UL << 20) -# define CRASH_ADDR_HIGH_MAX MAXMEM +# define CRASH_ADDR_HIGH_MAX (1ULL < 46) #endif static int __init reserve_crashkernel_low(void) -- 2.17.2