From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f71.google.com (mail-pa0-f71.google.com [209.85.220.71]) by kanga.kvack.org (Postfix) with ESMTP id 23BF96B0253 for ; Thu, 4 Aug 2016 04:02:58 -0400 (EDT) Received: by mail-pa0-f71.google.com with SMTP id ag5so395427865pad.2 for ; Thu, 04 Aug 2016 01:02:58 -0700 (PDT) Received: from sender153-mail.zoho.com (sender153-mail.zoho.com. [74.201.84.153]) by mx.google.com with ESMTPS id zd5si13417409pac.155.2016.08.04.01.02.57 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 04 Aug 2016 01:02:57 -0700 (PDT) From: zijun_hu Subject: [PATCH] mm/vmalloc: fix align value calculation error Message-ID: <57A2F6A3.9080908@zoho.com> Date: Thu, 4 Aug 2016 16:02:43 +0800 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , tj@kernel.org, hannes@cmpxchg.org Cc: mhocko@kernel.org, minchan@kernel.org, zijun_hu@htc.com, rientjes@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754089AbcHDIDA (ORCPT ); Thu, 4 Aug 2016 04:03:00 -0400 Received: from sender153-mail.zoho.com ([74.201.84.153]:21950 "EHLO sender153-mail.zoho.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750736AbcHDIC4 (ORCPT ); Thu, 4 Aug 2016 04:02:56 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=zapps768; d=zoho.com; h=to:from:cc:subject:message-id:date:user-agent:mime-version:content-type; b=ZkYGcyGLBsN7DIufj9YMcpi06E+OFU7R/YSzFyolg13iJ8L/jhDnulilJanZleIm853FuzbpKVXI c8n5gA9ulZKUT0v9P6nUXwpxQgcg+YUGuJXncCfSDctZcEKblRzP To: Andrew Morton , tj@kernel.org, hannes@cmpxchg.org From: zijun_hu Cc: mhocko@kernel.org, minchan@kernel.org, zijun_hu@htc.com, rientjes@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH] mm/vmalloc: fix align value calculation error Message-ID: <57A2F6A3.9080908@zoho.com> Date: Thu, 4 Aug 2016 16:02:43 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>From e40d1066f61394992e0167f259001ae9d2581dc1 Mon Sep 17 00:00:00 2001 From: zijun_hu Date: Thu, 4 Aug 2016 14:22:52 +0800 Subject: [PATCH] mm/vmalloc: fix align value calculation error it causes double align requirement for __get_vm_area_node() if parameter size is power of 2 and VM_IOREMAP is set in parameter flags it is fixed by using order_base_2 instead of fls_long() due to lack of get_count_order() for long parameter Signed-off-by: zijun_hu --- mm/vmalloc.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 91f44e7..8b17c51 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1357,11 +1357,19 @@ static struct vm_struct *__get_vm_area_node(unsigned long size, { struct vmap_area *va; struct vm_struct *area; + int ioremap_size_order; BUG_ON(in_interrupt()); - if (flags & VM_IOREMAP) - align = 1ul << clamp_t(int, fls_long(size), - PAGE_SHIFT, IOREMAP_MAX_ORDER); + if (flags & VM_IOREMAP) { + if (unlikely(size < 2)) + ioremap_size_order = size; + else if (unlikely((signed long)size < 0)) + ioremap_size_order = sizeof(size) * 8; + else + ioremap_size_order = order_base_2(size); + align = 1ul << clamp_t(int, ioremap_size_order, PAGE_SHIFT, + IOREMAP_MAX_ORDER); + } size = PAGE_ALIGN(size); if (unlikely(!size)) -- 1.9.1