Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757863AbYH1U4k (ORCPT ); Thu, 28 Aug 2008 16:56:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756170AbYH1U4R (ORCPT ); Thu, 28 Aug 2008 16:56:17 -0400 Received: from fxip-0047f.externet.hu ([88.209.222.127]:36914 "EHLO pomaz-ex.szeredi.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755823AbYH1U4Q (ORCPT ); Thu, 28 Aug 2008 16:56:16 -0400 To: hpa@kernel.org CC: miklos@szeredi.hu, tj@kernel.org, fuse-devel@lists.sourceforge.net, greg@kroah.com, linux-kernel@vger.kernel.org In-reply-to: <48B708C4.4000405@kernel.org> (hpa@kernel.org) Subject: Re: [PATCH 5/7] FUSE: implement ioctl support References: <1219945263-21074-1-git-send-email-tj@kernel.org> <1219945263-21074-6-git-send-email-tj@kernel.org> <48B6EC83.1070207@kernel.org> <48B6EE36.5070209@kernel.org> <48B6F7C5.3020204@kernel.org> <48B708C4.4000405@kernel.org> Message-Id: From: Miklos Szeredi Date: Thu, 28 Aug 2008 22:55:59 +0200 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 752 Lines: 19 On Thu, 28 Aug 2008, H. Peter Anvin wrote: > This is *hard* to get right, and we screw this up in the kernel with > painful regularity. The throught of having user-space processes, which > don't have access to the kernel locking primitives and functions like > copy_from_user() dealing with this stuff scares me crazy. What issues exactly are you thinking of? > That is why I'm suggesting using an in-kernel linearizer. Lots of complexity, ugh... Even Tejun's current scheme is better IMO. Miklos -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/