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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F1CCC8300A for ; Thu, 30 Apr 2020 11:39:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2AAF220775 for ; Thu, 30 Apr 2020 11:39:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588246768; bh=2rv/Th+U2tvUwoYnI9XJB61R1uEh9ov5BSgYIC5BZ7Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=cjrTatG6EPkMMv/cP9F8ghVV9xQS1mjMOY7XhwSsijY4cB8nOuiivfMoUKW3RR5sF /UPFSCCzUVvGjurf5ArcRuF8gyUohhDxQvHwRnap3Os7smZa3oIoNKTcQqYW18EWmD FMrIDeLbdI7lcKFC3n3nxLzvG5VASoQOGy09u4Iw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726789AbgD3Lj1 (ORCPT ); Thu, 30 Apr 2020 07:39:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:44020 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726636AbgD3Lj0 (ORCPT ); Thu, 30 Apr 2020 07:39:26 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BE2192076D; Thu, 30 Apr 2020 11:39:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588246765; bh=2rv/Th+U2tvUwoYnI9XJB61R1uEh9ov5BSgYIC5BZ7Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=k29nbFT/ev2JNmZkIbIni5U6RVaAGwptOaa/IDd9bcTSXbPY2vVCM9jpToRNnIHv8 r9meXIEYdgsv59NHVeo/qW74RI3hVsR0P2ropIAUdsdmYpEX/OHdGqS8CG5u8nwsY0 iflC7ZZNThZCxtLxZoJiH6z06rlyNZrLdZGiEIPg= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.92) (envelope-from ) id 1jU7XI-0080nh-3G; Thu, 30 Apr 2020 12:39:24 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 30 Apr 2020 12:39:24 +0100 From: Marc Zyngier To: Zenghui Yu Cc: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, James Morse , Julien Thierry , Suzuki K Poulose , Eric Auger Subject: Re: [PATCH] KVM: arm64: vgic-v4: Initialize GICv4.1 even in the absence of a virtual ITS In-Reply-To: <5b23b938-f71f-5523-6d7e-027bcca98dd4@huawei.com> References: <20200425094426.162962-1-maz@kernel.org> <5b23b938-f71f-5523-6d7e-027bcca98dd4@huawei.com> User-Agent: Roundcube Webmail/1.4.3 Message-ID: X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: yuzenghui@huawei.com, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, eric.auger@redhat.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Hi Zenghui, On 2020-04-30 12:24, Zenghui Yu wrote: > Hi Marc, > > On 2020/4/25 17:44, Marc Zyngier wrote: >> KVM now expects to be able to use HW-accelerated delivery of vSGIs >> as soon as the guest has enabled thm. Unfortunately, we only > them >> initialize the GICv4 context if we have a virtual ITS exposed to >> the guest. >> >> Fix it by always initializing the GICv4.1 context if it is >> available on the host. >> >> Fixes: 2291ff2f2a56 ("KVM: arm64: GICv4.1: Plumb SGI implementation >> selection in the distributor") >> Signed-off-by: Marc Zyngier >> --- >> virt/kvm/arm/vgic/vgic-init.c | 9 ++++++++- >> virt/kvm/arm/vgic/vgic-mmio-v3.c | 3 ++- >> 2 files changed, 10 insertions(+), 2 deletions(-) >> >> diff --git a/virt/kvm/arm/vgic/vgic-init.c >> b/virt/kvm/arm/vgic/vgic-init.c >> index a963b9d766b73..8e6f350c3bcd1 100644 >> --- a/virt/kvm/arm/vgic/vgic-init.c >> +++ b/virt/kvm/arm/vgic/vgic-init.c >> @@ -294,8 +294,15 @@ int vgic_init(struct kvm *kvm) >> } >> } >> - if (vgic_has_its(kvm)) { >> + if (vgic_has_its(kvm)) >> vgic_lpi_translation_cache_init(kvm); >> + >> + /* >> + * If we have GICv4.1 enabled, unconditionnaly request enable the >> + * v4 support so that we get HW-accelerated vSGIs. Otherwise, only >> + * enable it if we present a virtual ITS to the guest. >> + */ >> + if (vgic_supports_direct_msis(kvm)) { >> ret = vgic_v4_init(kvm); >> if (ret) >> goto out; >> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c >> b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> index e72dcc4542475..26b11dcd45524 100644 >> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c >> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> @@ -50,7 +50,8 @@ bool vgic_has_its(struct kvm *kvm) >> bool vgic_supports_direct_msis(struct kvm *kvm) >> { >> - return kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm); >> + return (kvm_vgic_global_state.has_gicv4_1 || >> + (kvm_vgic_global_state.has_gicv4 && vgic_has_its(kvm))); >> } > > Not related to this patch, but I think that the function name can be > improved a bit after this change. It now indicates whether the vGIC > supports direct MSIs injection *or* direct SGIs injection, not just > MSIs. And if vgic_has_its() is false, we don't even support MSIs. Yes, I noticed that too. But in the spirit of keeping the change minimal and avoid later conflicts with potential fixes, I decided against changing it right now. > The fix itself looks correct to me, > > Reviewed-by: Zenghui Yu Thanks, M. -- Jazz is not dead. It just smells funny...