From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 5BD8B6B016B for ; Thu, 25 Aug 2011 20:03:05 -0400 (EDT) Date: Thu, 25 Aug 2011 17:03:02 -0700 From: Andrew Morton Subject: Re: [PATCH -v2] debug-pagealloc: add support for highmem pages Message-Id: <20110825170302.81ed210c.akpm@linux-foundation.org> In-Reply-To: <1314281649-21508-1-git-send-email-akinobu.mita@gmail.com> References: <1314281649-21508-1-git-send-email-akinobu.mita@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Akinobu Mita Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org On Thu, 25 Aug 2011 23:14:09 +0900 Akinobu Mita wrote: > This adds support for highmem pages poisoning and verification to the > debug-pagealloc feature for no-architecture support. > Sorry, I had a brainfart. kmap_atomic() internally does the preempt_disable() (actually pagefault_disable()). --- a/mm/debug-pagealloc.c~debug-pagealloc-add-support-for-highmem-pages-fix +++ a/mm/debug-pagealloc.c @@ -23,14 +23,11 @@ static inline bool page_poison(struct pa static void poison_page(struct page *page) { - void *addr; + void *addr = kmap_atomic(page); - preempt_disable(); - addr = kmap_atomic(page); set_page_poison(page); memset(addr, PAGE_POISON, PAGE_SIZE); kunmap_atomic(addr); - preempt_enable(); } static void poison_pages(struct page *page, int n) @@ -82,12 +79,10 @@ static void unpoison_page(struct page *p if (!page_poison(page)) return; - preempt_disable(); addr = kmap_atomic(page); check_poison_mem(addr, PAGE_SIZE); clear_page_poison(page); kunmap_atomic(addr); - preempt_enable(); } static void unpoison_pages(struct page *page, int n) _ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org