From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751318Ab0CSTZg (ORCPT ); Fri, 19 Mar 2010 15:25:36 -0400 Received: from hera.kernel.org ([140.211.167.34]:40977 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750865Ab0CSTZf (ORCPT ); Fri, 19 Mar 2010 15:25:35 -0400 Message-ID: <4BA3CF67.9000107@kernel.org> Date: Fri, 19 Mar 2010 12:24:23 -0700 From: Yinghai Lu User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.8) Gecko/20100228 SUSE/3.0.3-1.1.1 Thunderbird/3.0.3 MIME-Version: 1.0 To: Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" CC: linux-kernel@vger.kernel.org, Ian Campbell , Yinghai Lu , Peter Zijlstra , Linus Torvalds Subject: [PATCH] x86: do not free zero sized per cpu areas References: <4B914A61.20409@kernel.org> In-Reply-To: <4B914A61.20409@kernel.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ian Campbell This avoids an infinite loop in free_early_partial(). Add a warning to free_early_partial to catch future problems. Signed-off-by: Ian Campbell Signed-off-by: Yinghai Lu Cc: Peter Zijlstra Cc: Ingo Molnar --- arch/x86/kernel/setup_percpu.c | 3 ++- kernel/early_res.c | 5 +++++ 2 files changed, 7 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index ef6370b..89a3205 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -140,7 +140,8 @@ static void __init pcpu_fc_free(void *ptr, size_t size) #ifdef CONFIG_NO_BOOTMEM u64 start = __pa(ptr); u64 end = start + size; - free_early_partial(start, end); + if (start < end) + free_early_partial(start, end); #else free_bootmem(__pa(ptr), size); #endif diff --git a/kernel/early_res.c b/kernel/early_res.c index 3cb2c66..f3a861b 100644 --- a/kernel/early_res.c +++ b/kernel/early_res.c @@ -333,6 +333,11 @@ void __init free_early_partial(u64 start, u64 end) struct early_res *r; int i; + if (WARN_ONCE(start >= end, + "free_early_partial got wrong start/end %#llx/%#llx\n", + start, end)) + return; + try_next: i = find_overlapped_early(start, end); if (i >= max_early_res) -- 1.5.6.5