Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751917AbbGMQpe (ORCPT ); Mon, 13 Jul 2015 12:45:34 -0400 Received: from mail-ob0-f173.google.com ([209.85.214.173]:35053 "EHLO mail-ob0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751327AbbGMQpd (ORCPT ); Mon, 13 Jul 2015 12:45:33 -0400 MIME-Version: 1.0 In-Reply-To: References: <1436591360-16210-1-git-send-email-brgerst@gmail.com> <1436591360-16210-2-git-send-email-brgerst@gmail.com> Date: Mon, 13 Jul 2015 12:45:32 -0400 Message-ID: Subject: Re: [PATCH 1/5] x86/vm86: Move userspace accesses to do_sys_vm86() From: Brian Gerst To: Andy Lutomirski Cc: X86 ML , "linux-kernel@vger.kernel.org" , Ingo Molnar , "H. Peter Anvin" , Denys Vlasenko , Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1482 Lines: 36 On Sat, Jul 11, 2015 at 12:37 PM, Andy Lutomirski wrote: > On Fri, Jul 10, 2015 at 10:09 PM, Brian Gerst wrote: >> Move the userspace accesses down into the common function in >> preparation for the next set of patches. >> > > One thing I don't like about the current code that makes these patches > harder to review is the bizarre approach to copying. If you changed > this: > >> - tmp = copy_vm86_regs_from_user(&info.regs, &v86->regs, >> - offsetof(struct kernel_vm86_struct, vm86plus) - >> - sizeof(info.regs)); > > into a normal field-by-field get_user / copy_from_user (the latter for > the big regs struct) then it would be clear what the ABI is and it > would be much easier to read the patches and confirm that you aren't > accidentally changing the ABI. > > You could also get rid of the constraint that certain fields in > apparently kernel-internal structs had to be in a certain order. > > Other than that, patches 1-4 look good on cursory inspection. I'll > look more carefully later. I need to think about patch 5 more. > > --Andy Any other comments before I start working on v2? -- Brian Gerst -- 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/