From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([65.50.211.133]:38572 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750997AbdBFOgy (ORCPT ); Mon, 6 Feb 2017 09:36:54 -0500 Date: Mon, 6 Feb 2017 06:36:48 -0800 From: Christoph Hellwig Subject: Re: [PATCH] mm: replace FAULT_FLAG_SIZE with parameter to huge_fault Message-ID: <20170206143648.GA461@infradead.org> References: <148615748258.43180.1690152053774975329.stgit@djiang5-desk3.ch.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <148615748258.43180.1690152053774975329.stgit@djiang5-desk3.ch.intel.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Dave Jiang Cc: akpm@linux-foundation.org, mawilcox@microsoft.com, linux-nvdimm@lists.01.org, dave.hansen@linux.intel.com, linux-xfs@vger.kernel.org, linux-mm@kvack.org, vbabka@suse.cz, jack@suse.com, linux-ext4@vger.kernel.org, kirill.shutemov@linux.intel.com On Fri, Feb 03, 2017 at 02:31:22PM -0700, Dave Jiang wrote: > Since the introduction of FAULT_FLAG_SIZE to the vm_fault flag, it has > been somewhat painful with getting the flags set and removed at the > correct locations. More than one kernel oops was introduced due to > difficulties of getting the placement correctly. Removing the flag > values and introducing an input parameter to huge_fault that indicates > the size of the page entry. This makes the code easier to trace and > should avoid the issues we see with the fault flags where removal of the > flag was necessary in the fallback paths. Why is this not in struct vm_fault? Also can be use this opportunity to fold ->huge_fault into ->fault?