From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757788AbaHZLic (ORCPT ); Tue, 26 Aug 2014 07:38:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:9951 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757478AbaHZLib (ORCPT ); Tue, 26 Aug 2014 07:38:31 -0400 From: Baoquan He To: linux-kernel@vger.kernel.org, akpm@linux-foundation.org Cc: Baoquan He Subject: [PATCH v3] not adding modules range to kcore if it's equal to vmcore range Date: Tue, 26 Aug 2014 19:38:25 +0800 Message-Id: <1409053105-3631-1-git-send-email-bhe@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On some ARCHs modules range is eauql to vmalloc range. E.g on i686 "#define MODULES_VADDR VMALLOC_START" "#define MODULES_END VMALLOC_END" This will cause 2 duplicate program segments in /proc/kcore, and no any flag to indicate both of them are different. This is confusing. And usually people who need check the elf header or read the content of kcore will check memory ranges. Two program segments which are the same completely can't give any help on this. So in this patch a judgment added to check if modules range is equal to or included in vmalloc range completely. If yes, just skip adding the modules range. If and only if modules range is not completely included in vmalloc range just add it since the part out of vmalloc range need be accessible. Signed-off-by: Baoquan He --- fs/proc/kcore.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c index 6df8d07..a4b7ff1 100644 --- a/fs/proc/kcore.c +++ b/fs/proc/kcore.c @@ -610,8 +610,11 @@ static void __init proc_kcore_text_init(void) struct kcore_list kcore_modules; static void __init add_modules_range(void) { - kclist_add(&kcore_modules, (void *)MODULES_VADDR, + if ( (MODULES_VADDR != VMALLOC_START) && + (MODULES_END <= VMALLOC_END) ) { + kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_END - MODULES_VADDR, KCORE_VMALLOC); + } } #else static void __init add_modules_range(void) -- 1.9.0