From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id F1C606B0038 for ; Tue, 3 Oct 2017 11:37:01 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id y192so23714521pgd.0 for ; Tue, 03 Oct 2017 08:37:01 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [65.50.211.133]) by mx.google.com with ESMTPS id 7si200102pgd.489.2017.10.03.08.37.01 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 03 Oct 2017 08:37:01 -0700 (PDT) Date: Tue, 3 Oct 2017 08:37:00 -0700 From: Christoph Hellwig Subject: Re: [PATCH v4 4/5] cramfs: add mmap support Message-ID: <20171003153659.GA31600@infradead.org> References: <20170927233224.31676-1-nicolas.pitre@linaro.org> <20170927233224.31676-5-nicolas.pitre@linaro.org> <20171001083052.GB17116@infradead.org> <20171003145732.GA8890@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Nicolas Pitre Cc: Christoph Hellwig , Richard Weinberger , Alexander Viro , "linux-mm@kvack.org" , linux-fsdevel , "linux-embedded@vger.kernel.org" , LKML , Chris Brandt On Tue, Oct 03, 2017 at 11:30:50AM -0400, Nicolas Pitre wrote: > Unless you have a better scheme altogether to suggest of course, given > the existing constraints. I still can't understand why this convoluted fault path that finds vma, attempts with all kinds of races and then tries to update things like vm_ops is even nessecary. We have direct mappings of physical address perfectly working in the DAX code (even with write support!) or in drivers using remap_pfn_range so a really good explanation why neither scheme can be used is needed first. -- 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