From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752408AbeENVAq (ORCPT ); Mon, 14 May 2018 17:00:46 -0400 Received: from isilmar-4.linta.de ([136.243.71.142]:33950 "EHLO isilmar-4.linta.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752087AbeENVAp (ORCPT ); Mon, 14 May 2018 17:00:45 -0400 Date: Mon, 14 May 2018 22:24:45 +0200 From: Dominik Brodowski To: Mark Rutland , Dave Martin Cc: linux-arm-kernel@lists.infradead.org, marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, james.morse@arm.com, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 08/18] arm64: convert raw syscall invocation to C Message-ID: <20180514202445.GA26773@light.dominikbrodowski.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180514125351.GK7753@e103592.cambridge.arm.com> <20180514114104.oubxdf526hf2m6t5@lakrids.cambridge.arm.com> User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 14, 2018 at 12:41:10PM +0100, Mark Rutland wrote: > I agree it would be nicer if it had a wrapper that took a pt_regs, even > if it does nothing with it. > > We can't use SYSCALL_DEFINE0() due to the fault injection muck, we'd > need a ksys_ni_syscall() for our traps.c logic, and adding this > uniformly would involve some arch-specific rework for x86, too, so I > decided it was not worth the effort. Couldn't you just open-code the "return -ENOSYS;" in traps.c? Error injection has no reasonable stable ABI/API expectations, so that's not a show-stopper either. Thanks, Dominik From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@dominikbrodowski.net (Dominik Brodowski) Date: Mon, 14 May 2018 22:24:45 +0200 Subject: [PATCH 08/18] arm64: convert raw syscall invocation to C In-Reply-To: <20180514125351.GK7753@e103592.cambridge.arm.com> <20180514114104.oubxdf526hf2m6t5@lakrids.cambridge.arm.com> Message-ID: <20180514202445.GA26773@light.dominikbrodowski.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Mon, May 14, 2018 at 12:41:10PM +0100, Mark Rutland wrote: > I agree it would be nicer if it had a wrapper that took a pt_regs, even > if it does nothing with it. > > We can't use SYSCALL_DEFINE0() due to the fault injection muck, we'd > need a ksys_ni_syscall() for our traps.c logic, and adding this > uniformly would involve some arch-specific rework for x86, too, so I > decided it was not worth the effort. Couldn't you just open-code the "return -ENOSYS;" in traps.c? Error injection has no reasonable stable ABI/API expectations, so that's not a show-stopper either. Thanks, Dominik