Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967436AbeAOMwg (ORCPT + 1 other); Mon, 15 Jan 2018 07:52:36 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:52190 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965544AbeAOMwc (ORCPT ); Mon, 15 Jan 2018 07:52:32 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Kirill A. Shutemov" , Baoquan He , Dave Young , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Vivek Goyal , Andrew Morton , Linus Torvalds Subject: [PATCH 4.14 087/118] kdump: write correct address of mem_section into vmcoreinfo Date: Mon, 15 Jan 2018 13:35:14 +0100 Message-Id: <20180115123420.615854642@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180115123415.325497625@linuxfoundation.org> References: <20180115123415.325497625@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kirill A. Shutemov commit a0b1280368d1e91ab72f849ef095b4f07a39bbf1 upstream. Depending on configuration mem_section can now be an array or a pointer to an array allocated dynamically. In most cases, we can continue to refer to it as 'mem_section' regardless of what it is. But there's one exception: '&mem_section' means "address of the array" if mem_section is an array, but if mem_section is a pointer, it would mean "address of the pointer". We've stepped onto this in kdump code. VMCOREINFO_SYMBOL(mem_section) writes down address of pointer into vmcoreinfo, not array as we wanted. Let's introduce VMCOREINFO_SYMBOL_ARRAY() that would handle the situation correctly for both cases. Link: http://lkml.kernel.org/r/20180112162532.35896-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov Fixes: 83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y") Acked-by: Baoquan He Acked-by: Dave Young Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Greg Kroah-Hartman Cc: Dave Young Cc: Baoquan He Cc: Vivek Goyal Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- include/linux/crash_core.h | 2 ++ kernel/crash_core.c | 2 +- 2 files changed, 3 insertions(+), 1 deletion(-) --- a/include/linux/crash_core.h +++ b/include/linux/crash_core.h @@ -42,6 +42,8 @@ phys_addr_t paddr_vmcoreinfo_note(void); vmcoreinfo_append_str("PAGESIZE=%ld\n", value) #define VMCOREINFO_SYMBOL(name) \ vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name) +#define VMCOREINFO_SYMBOL_ARRAY(name) \ + vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)name) #define VMCOREINFO_SIZE(name) \ vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \ (unsigned long)sizeof(name)) --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -409,7 +409,7 @@ static int __init crash_save_vmcoreinfo_ VMCOREINFO_SYMBOL(contig_page_data); #endif #ifdef CONFIG_SPARSEMEM - VMCOREINFO_SYMBOL(mem_section); + VMCOREINFO_SYMBOL_ARRAY(mem_section); VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS); VMCOREINFO_STRUCT_SIZE(mem_section); VMCOREINFO_OFFSET(mem_section, section_mem_map);