From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2FB54C433FE for ; Wed, 30 Nov 2022 16:54:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229798AbiK3Qym (ORCPT ); Wed, 30 Nov 2022 11:54:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229617AbiK3Qyk (ORCPT ); Wed, 30 Nov 2022 11:54:40 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 453AB769F1 for ; Wed, 30 Nov 2022 08:54:39 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 090E1B81BE0 for ; Wed, 30 Nov 2022 16:54:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C8EF3C433D6; Wed, 30 Nov 2022 16:54:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1669827275; bh=NPbwscevJ/Y3cUJ4lLTK4IHAQHxWH+blvVW97vUbNJs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=IopcPGzRnjPfR7tXxcAvjZVlJBzbmaMKv8vPe1GxGnAW/jKFO/2qkYgcakdorp03N /7ieculngRK2u2q3p7aZ2Ei8yOfK9MEOeqKXiHCRJF9ELGrMKxxfTh2h2wa1I3cedk aCX6tP+PImlAov9DcqNRZURGydjWCwmv3KSLQ/VCc+IqCxsucVMvKWaDlr7ByK9y1R 5m66SH/13+vl5uzgUevtTnKC9WGuYOgDwCjWZU6noFbwEJRDiSiNySd/V9hodQD6n+ RAHIcKehnvdtQkQE8dq/6UpcrZiyeDTkM/DqRUGQ7AODaO1kz7Gx31YTEi3znIMXwN aZwOJcG3MRDcw== Received: from sofa.misterjones.org ([185.219.108.64] helo=goblin-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1p0QLx-009dDQ-GT; Wed, 30 Nov 2022 16:54:33 +0000 Date: Wed, 30 Nov 2022 16:54:33 +0000 Message-ID: <86a648mlh2.wl-maz@kernel.org> From: Marc Zyngier To: Oliver Upton Cc: James Morse , Alexandru Elisei , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kvmarm@lists.linux.dev Subject: Re: [PATCH 0/4] KVM: arm64: Parallel access faults In-Reply-To: <20221129191946.1735662-1-oliver.upton@linux.dev> References: <20221129191946.1735662-1-oliver.upton@linux.dev> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: oliver.upton@linux.dev, james.morse@arm.com, alexandru.elisei@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, kvmarm@lists.linux.dev X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, 29 Nov 2022 19:19:42 +0000, Oliver Upton wrote: > > When I implemented the parallel faults series I was mostly focused on > improving the performance of 8.1+ implementations which bring us > FEAT_HAFDBS. In so doing, I failed to put access faults on the read side > of the MMU lock. > > Anyhow, this small series adds support for handling access faults in > parallel, piling on top of the infrastructure from the first parallel > faults series. As most large systems I'm aware of are 8.1+ anyway, I > don't expect this series to provide significant uplift beyond some > oddball machines Marc has lying around. Don't get me wrong, I'd love to > have a D05 to play with too... Hey, that puts the whole fruity range of machines in the oddball department too, as they don't implement any of HAFDBS! The feature being optional, I wouldn't be surprised if others would either not implement it (or disable it to hide that it is b0rk3n...). M. -- Without deviation from the norm, progress is not possible.