From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lb0-f175.google.com (mail-lb0-f175.google.com [209.85.217.175]) by kanga.kvack.org (Postfix) with ESMTP id 43B396B0038 for ; Tue, 17 Nov 2015 12:26:58 -0500 (EST) Received: by lbbkw15 with SMTP id kw15so9933461lbb.0 for ; Tue, 17 Nov 2015 09:26:57 -0800 (PST) Received: from mail-lf0-x241.google.com (mail-lf0-x241.google.com. [2a00:1450:4010:c07::241]) by mx.google.com with ESMTPS id e20si31405956lfi.75.2015.11.17.09.26.56 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 17 Nov 2015 09:26:56 -0800 (PST) Received: by lfu94 with SMTP id 94so1181611lfu.1 for ; Tue, 17 Nov 2015 09:26:56 -0800 (PST) From: Piotr Kwapulinski Subject: [PATCH] mm/mmap.c: remove incorrect MAP_FIXED flag comparison from mmap_region Date: Tue, 17 Nov 2015 18:26:38 +0100 Message-Id: <1447781198-5496-1-git-send-email-kwapulinski.piotr@gmail.com> In-Reply-To: <20151117161928.GA9611@redhat.com> References: <20151117161928.GA9611@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: mhocko@suse.com Cc: oleg@redhat.com, akpm@linux-foundation.org, cmetcalf@ezchip.com, mszeredi@suse.cz, viro@zeniv.linux.org.uk, dave@stgolabs.net, kirill.shutemov@linux.intel.com, n-horiguchi@ah.jp.nec.com, aarcange@redhat.com, iamjoonsoo.kim@lge.com, jack@suse.cz, xiexiuqi@huawei.com, vbabka@suse.cz, Vineet.Gupta1@synopsys.com, riel@redhat.com, gang.chen.5i5j@gmail.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Piotr Kwapulinski The following flag comparison in mmap_region is not fully correct: if (!(vm_flags & MAP_FIXED)) The vm_flags should not be compared with MAP_FIXED (0x10). It is a bit confusing. This condition is almost always true since VM_MAYREAD (0x10) flag is almost always set by default. This patch removes this condition. Signed-off-by: Piotr Kwapulinski --- mm/mmap.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 2ce04a6..02422ea 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1547,13 +1547,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr, if (!may_expand_vm(mm, len >> PAGE_SHIFT)) { unsigned long nr_pages; - /* - * MAP_FIXED may remove pages of mappings that intersects with - * requested mapping. Account for the pages it would unmap. - */ - if (!(vm_flags & MAP_FIXED)) - return -ENOMEM; - nr_pages = count_vma_pages_range(mm, addr, addr + len); if (!may_expand_vm(mm, (len >> PAGE_SHIFT) - nr_pages)) -- 2.6.2 -- 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/ . Don't email: email@kvack.org