From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BCE78606A328 for ; Mon, 26 Oct 2026 21:30:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=scgVYo+n; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Tv6/cPLh DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=wnInlAoM7eCnwc4pQzCJ3JjKUOaq29EJiA2dB7FE3lc=; b=scgVYo+nZVNhc6xguPywEPqw8d hMd2Ra0ze4o2Wn0nny8FYNdMfP9WCqyLSFz9EiDPWOIU82AayHcP0vS66LifwUUAjCJr860toKyr6 8qepNDk0JkpUQkYrtmDP37JpTP7c/10oc0MO1nHf7UtAm2jdjsBt2dpWymXfgnLlRGxkVpzHpWeVA b1mI9I/8WObzf5+kWGqddpD5XaMXhAqj1wg18wS6kGDdejQ7uECDPYiQx9qFFoFirlQgHkKgECUdY +5LEFHPBLHSjcTDbKTA841ZM8oiI3vSr+lht1tCh/tyMpKBy/XHGVsmnEIkxPNGtnkj9vq1EmX1t7 9qGoZxPg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLSGl-00000003I5I-3T4w; Mon, 26 Oct 2026 21:30:15 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLSGj-00000003I5A-3LWm for linux-arm-kernel@lists.infradead.org; Mon, 26 Oct 2026 21:30:13 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id D7F86601F0; Mon, 26 Oct 2026 21:30:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 58B081F01829; Mon, 26 Oct 2026 21:30:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793050211; bh=wnInlAoM7eCnwc4pQzCJ3JjKUOaq29EJiA2dB7FE3lc=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=Tv6/cPLh4sVaKXCK89oJRyF7wE8NcPivUztYh15k6VmzCpjEp2C5Fzg2+rfb/Hcbb xTJWKm66k1H4p5qcWHcV9aF+DPo0UJNegdI439bi3n3PeXtlKUIV87EkAQLZeqgH1P GWCDtb+BEg0x/d5SU7bB+uAPMyh+wxK2/20v/alpOXo+GNNUoDpr614XE8MzjldNO3 Y1Rdm/bJqjDAymCb1ai5mV+DldMj6FiZjQJdaK7lnZ/3xkIFmAiT4ClF7cdzgqPXd5 11mx2fsBPP+ZhjtQlBuAQ9i4uj4GTRCmcmnLelhhdsorLoH0P7DAW/zk4bdgvjGXXP I3ENK1ifhMJXQ== Date: Mon, 26 Oct 2026 14:30:09 -0700 From: Oliver Upton To: Marc Zyngier Cc: Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Raghavendra Rao Ananta , Eric Auger , Will Deacon , Fuad Tabba , kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] KVM: arm64: vgic-v4: Don't allocate vPEs for a GICv2 VM Message-ID: References: <20261026152639.3926498-1-fuad.tabba@linux.dev> <20261026152639.3926498-2-fuad.tabba@linux.dev> <87qzhc8ce6.wl-maz@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87qzhc8ce6.wl-maz@kernel.org> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-6.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On Mon, Oct 26, 2026 at 07:55:45PM +0000, Marc Zyngier wrote: > On Mon, 26 Oct 2026 19:12:23 +0000, > Oliver Upton wrote: > > > > On Mon, Oct 26, 2026 at 03:26:38PM +0000, Fuad Tabba wrote: > > > KVM can run a GICv2 VM on a GICv4.0 host whose CPU interface supports > > > legacy operation. > > > > I'm pretty sure there's no IP out there that has GICv4.0 and legacy > > mode... > > My favourite space heater, HiSi D05, says otherwise: 64 A72, > GICv4.0. Remember that it is the *CPU* that provides compat mode, and > not the GIC. Well I forgot that one got glued together. Good thing you're on the hook for fixes this round then ;) Thanks, Olier