From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 31 Oct 2006 12:48:13 +0000 (GMT) From: Hugh Dickins Subject: Re: [RFC] reduce hugetlb_instantiation_mutex usage In-Reply-To: <20061031110540.GA14172@localhost.localdomain> Message-ID: References: <20061031031703.GA7220@localhost.localdomain> <000001c6fcab$8fe56320$5181030a@amr.corp.intel.com> <20061031110540.GA14172@localhost.localdomain> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: 'David Gibson' Cc: "Chen, Kenneth W" , g@ozlabs.org, Andrew Morton , 'Christoph Lameter' , bill.irwin@oracle.com, Adam Litke , linux-mm@kvack.org List-ID: On Tue, 31 Oct 2006, 'David Gibson' wrote: > On Mon, Oct 30, 2006 at 09:15:20PM -0800, Chen, Kenneth W wrote: > > > > Instead, I'm asking how private mapping protect race between file truncation > > and fault? For shared mapping, it is clear to me that we are using lock_page > > to protect file truncate with fault. But I don't see that protection with > > private mapping in current upstream kernel. > > Oh, ok. I can't see how it matters in the PRIVATE case, given that > truncate() won't, and shouldn't, truncate privately mapped pages. Bzzt, it does and should (unless we decide to make hugetlbfs pages diverge from the standard for ordinary pages in this respect - could do, but that would require thought of its own). If you've been thinking otherwise, that may explain why some of the accounting goes wrong. Hugh -- 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