Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751533AbbLHV7E (ORCPT ); Tue, 8 Dec 2015 16:59:04 -0500 Received: from aserp1040.oracle.com ([141.146.126.69]:45158 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751094AbbLHV66 (ORCPT ); Tue, 8 Dec 2015 16:58:58 -0500 From: Daniel Kiper To: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org Cc: andrew.cooper3@citrix.com, david.vrabel@citrix.com, horms@verge.net.au, keir@xen.org, konrad.wilk@oracle.com Subject: [PATCH 04/14] crashdump/x86: Add print_crashkernel_region_size() function Date: Tue, 8 Dec 2015 22:57:37 +0100 Message-Id: <1449611867-15672-5-git-send-email-daniel.kiper@oracle.com> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1449611867-15672-1-git-send-email-daniel.kiper@oracle.com> References: <1449611867-15672-1-git-send-email-daniel.kiper@oracle.com> X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2390 Lines: 67 Crash kernel region size is available via sysfs on Linux running on bare metal. However, this does not work when Linux runs as Xen dom0. In this case Xen crash kernel region size should be established using __HYPERVISOR_kexec_op hypercall (Linux kernel kexec functionality does not make a lot of sense in Xen dom0). Sadly hypercalls are not easily accessible using shell scripts or something like that. Potentially we can check "xl dmesg" output for crashkernel option but this is not nice. So, let's add this functionality, for Linux running on bare metal and as Xen dom0, to kexec-tools. This way kdump scripts may establish crash kernel region size in one way regardless of platform. All burden of platform detection lies on kexec-tools. Figure (and unit) displayed by this new kexec-tools functionality is the same as one taken from /sys/kernel/kexec_crash_size. This patch just adds print_crashkernel_region_size() function, which prints crash kernel region size, for x86 arch. Next patches will add same named function for other archs supported by kexec-tools. Last patch of this series will export this functionality to the userspace via separate kexec utility option. Signed-off-by: Daniel Kiper --- kexec/arch/i386/crashdump-x86.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/kexec/arch/i386/crashdump-x86.c b/kexec/arch/i386/crashdump-x86.c index bbc0f35..10a56a8 100644 --- a/kexec/arch/i386/crashdump-x86.c +++ b/kexec/arch/i386/crashdump-x86.c @@ -1056,7 +1056,7 @@ static int crashkernel_mem_callback(void *UNUSED(data), int nr, return 0; } -int is_crashkernel_mem_reserved(void) +static int get_crashkernel_region(void) { int ret; @@ -1079,3 +1079,19 @@ int is_crashkernel_mem_reserved(void) return !!crash_reserved_mem_nr; } + +int is_crashkernel_mem_reserved(void) +{ + return get_crashkernel_region(); +} + +void print_crashkernel_region_size(void) +{ + uint64_t start, end; + + if (get_crashkernel_region()) { + get_crash_kernel_load_range(&start, &end); + printf("%lu\n", end - start + 1); + } else + printf("0\n"); +} -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/