From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78E1130D3E7; Sat, 25 Jul 2026 17:11:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784999471; cv=none; b=tZrIzJACSzVdBjRBz0ZKJFBWRiJs9RqHMrkJ+r5bgKSyOskVzmJFjBwDQVBZf+ZStXl6Pvos9yCkvWQUG1cEDGfLxneq0Bj0iujHzXzYqCjHa4LKiwcJokuXvWYcBqPxO57RVbAqbvwe1LZYw3EaHhMk46nFhqxAnd/c0jJzkGU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784999471; c=relaxed/simple; bh=lZpwIbBqLQCXfAzIy7Uj+PgklczwULQKP+kt74QNgvE=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=p6eQdh85E1Of2dYKKg4+Ngnvt16Y3+1LVuIXRf/ELcu+mSYXWRpkNgDuIXPmmqXSTfv4VtRNxPYP0RxT3ibCcr8JQbwbT1KXQc1WSo/Hg18rTzMag1PdXpX0PVIxdLGHcmO/CRWOQRkOedhHr7wVHDyTYqG0zdpCWTnkaCJlPtM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=naU1+Wy7; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="naU1+Wy7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 012C61F000E9; Sat, 25 Jul 2026 17:11:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784999470; bh=qCTMtTlGf8TX43MgfeK58BQDi0wVFj04WmzNNjZ51iQ=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=naU1+Wy7eleqJSfuA4Rog6PKICrFmxIas+IssKpPIQrkuBQpt2jxrLJDHX8gdGtrJ pjTPQyWk4hkvpVFNd0Z6SPusN596kaIckWxU3tZJFPlVZ0Zlmoc7OnCY1AjyAkZvBY e7nQp0vvNnSqNea9AKdb+LHSjaj0H4/ClWUmHS2gvco/f2EG3KIntTHNyRGKh9CPM6 wd8gkbUigOvA/fYWwxcSaa5YDl6anzNU8bwmo4nyxU/Rm4A2UqeJvwl+JaxfgPYCx7 ZILAzmX+3Bf7rnDb+ufosyuppRygiPxKNGrS7qoEhngKLPbUiXf3/Ja8BuOGMmeHrj qz9+2HGSydH8Q== Received: from sofa.misterjones.org ([185.219.108.64] helo=lobster-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1wnfu0-00000008nz7-0LzH; Sat, 25 Jul 2026 17:11:08 +0000 Date: Sat, 25 Jul 2026 18:12:31 +0100 Message-ID: <87wlujouww.wl-maz@kernel.org> From: Marc Zyngier To: Karl Mehltretter Cc: Oliver Upton , Fuad Tabba , Joey Gouly , Steffen Eiden , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] KVM: arm64: GICv2: Bound the INTID in vgic_v2_deactivate() In-Reply-To: <20260725154020.37305-1-kmehltretter@gmail.com> References: <20260725154020.37305-1-kmehltretter@gmail.com> 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/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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: kmehltretter@gmail.com, oupton@kernel.org, fuad.tabba@linux.dev, joey.gouly@arm.com, seiden@linux.ibm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Sat, 25 Jul 2026 16:40:20 +0100, Karl Mehltretter wrote: > > vgic_v2_deactivate() passes the INTID from a trapped GICV_DIR write to > vgic_get_vcpu_irq() without checking it against the number of > implemented interrupts. An out-of-range INTID makes the lookup return > NULL and triggers WARN_ON_ONCE(!irq). > > A guest using EOImode=1 can therefore raise a host warning, or panic a > host with panic_on_warn=1. > > The GICv3 counterpart rejects INTIDs outside the configured SGI, PPI and > SPI range before performing the lookup. Add the same check to the GICv2 > path. > > Fixes: 255de897e7fb ("KVM: arm64: GICv2: Handle deactivation via GICV_DIR traps") > Cc: stable@vger.kernel.org > Assisted-by: Claude:claude-opus-5 > Signed-off-by: Karl Mehltretter > --- > arch/arm64/kvm/vgic/vgic-v2.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/kvm/vgic/vgic-v2.c b/arch/arm64/kvm/vgic/vgic-v2.c > index cafa3cb32bda..42430c0fee07 100644 > --- a/arch/arm64/kvm/vgic/vgic-v2.c > +++ b/arch/arm64/kvm/vgic/vgic-v2.c > @@ -163,8 +163,12 @@ void vgic_v2_deactivate(struct kvm_vcpu *vcpu, u32 val) > cpuid = FIELD_GET(GENMASK_ULL(12, 10), val); > val &= ~GENMASK_ULL(12, 10); > > - /* We only deal with DIR when EOIMode==1 */ > - if (!(cpuif->vgic_vmcr & GICH_VMCR_EOI_MODE_MASK)) > + /* > + * We only deal with DIR when EOIMode==1, and only for SGI, > + * PPI or SPI. > + */ > + if (!(cpuif->vgic_vmcr & GICH_VMCR_EOI_MODE_MASK) || > + val >= vcpu->kvm->arch.vgic.nr_spis + VGIC_NR_PRIVATE_IRQS) > return; This duplicates the existing check, as GICv2 has no LPIs. I'd rather drop the WARN_ON() altogether. Thanks, M. -- Jazz isn't dead. It just smells funny.