From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f175.google.com (mail-wi0-f175.google.com [209.85.212.175]) by kanga.kvack.org (Postfix) with ESMTP id 003726B0253 for ; Mon, 14 Sep 2015 14:20:36 -0400 (EDT) Received: by wicfx3 with SMTP id fx3so143564816wic.0 for ; Mon, 14 Sep 2015 11:20:36 -0700 (PDT) Received: from mail-wi0-f176.google.com (mail-wi0-f176.google.com. [209.85.212.176]) by mx.google.com with ESMTPS id w11si18806092wie.106.2015.09.14.11.20.35 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 14 Sep 2015 11:20:35 -0700 (PDT) Received: by wicfx3 with SMTP id fx3so151506756wic.1 for ; Mon, 14 Sep 2015 11:20:35 -0700 (PDT) Date: Mon, 14 Sep 2015 21:20:33 +0300 From: "Kirill A. Shutemov" Subject: Re: LTP regressions due to 6dc296e7df4c ("mm: make sure all file VMAs have ->vm_ops set") Message-ID: <20150914182033.GA4165@node.dhcp.inet.fi> References: <20150914105346.GB23878@arm.com> <20150914115800.06242CE@black.fi.intel.com> <20150914170547.GA28535@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150914170547.GA28535@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Oleg Nesterov Cc: "Kirill A. Shutemov" , Will Deacon , hpa@zytor.com, luto@amacapital.net, dave.hansen@linux.intel.com, mingo@elte.hu, minchan@kernel.org, tglx@linutronix.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org On Mon, Sep 14, 2015 at 07:05:47PM +0200, Oleg Nesterov wrote: > On 09/14, Kirill A. Shutemov wrote: > > > > Fix is below. I don't really like it, but I cannot find any better > > solution. > > Me too... > > But this change "documents" the nasty special "vm_file && !vm_ops" case, and > I am not sure how we can remove it later... > > So perhaps we should change vma_is_anonymous() back to check ->fault too, > > static inline bool vma_is_anonymous(struct vm_area_struct *vma) > { > - return !vma->vm_ops; > + return !vma->vm_ops || !vma->vm_ops->fault; No. This would give a lot false positives from drives which setup page tables upfront and don't use ->fault at all. > } > > and remove the "vma->vm_file && !vma->vm_ops" checks in mmap_region() paths. > > I dunno. > > Oleg. > > -- > 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 -- Kirill A. Shutemov -- 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