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 758313932EA; Sun, 2 Aug 2026 15:55:22 +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=1785686123; cv=none; b=G7cMeyxDRC4po4QJK48JyMAinTON3CEYS6UgN2MTIH7dZUcOFDHMooeZitR5eSCugwgy3vlJtvhj7u/6ggArbVdfpPO60lVzEchrnT74+UKz3TUCHyfAqTX6PtwrC6ZqdiQ701zlzI3U9Rj4ZRuQXFauFDngRgj5XL1BskE/YCE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785686123; c=relaxed/simple; bh=qt2EYFITGr67nfW1GZRtTcJUhTZzABRUhuy6g6rW1ro=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=ZgOaUzVrYrodMaboRktHKjwa+dJNAWxRsf09izs+tc09IJpU8XVxW4HcYQa5TbzjDUfL6UzihQhcN4ZjogV1RglcwgEWFpPSpMO+h43vyun5Xh72zZ8HM9wKsh8yPXOW2ZLncOeykmIFhbRMhHMvqvHMFK4eVdvoEvzcd2NJawc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QTJSGIHm; 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="QTJSGIHm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CA671F000E9; Sun, 2 Aug 2026 15:55:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785686122; bh=zZ5H4eB7tZXCdSU5j4A/pThsIBip2dyKmzd/naErbyA=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=QTJSGIHmp7t1+XbvOwcW5t/LX7ZO577yRk3bxj7ro25XuEmNLeqdShjaajNmowTUB SJ/Mj3qy5G1PCtbsrw51ofWncwpwCfCqcFIxdHYQ3SXCwPo9CFuYptPQxhzcpRh64I zYjWVgFXhIPf6aR0Wwr/t+NqQUwji5YlP1gmfKCUa8uyKlKn+/qXpa+HTkXUSDG3kk e1rFZtj4Sh6oOHUqxl1RhGuy7wxH0PIhGA3IFaxLXvVpQBPZCpPhNBF7NPdXUW9xzc OP+1+iLrzaJMmo7k66kGl6knzV16Atdt2884VS3RQYSK4wQUwcGxQdNY2yuekRJeIc q6q6iSFUaEIPA== 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 1wqYX1-0000000BUNX-2Ni4; Sun, 02 Aug 2026 15:55:19 +0000 Date: Sun, 02 Aug 2026 16:55:20 +0100 Message-ID: <87jyq8plef.wl-maz@kernel.org> From: Marc Zyngier To: Fuad Tabba Cc: Oliver Upton , kvmarm@lists.linux.dev, stable@vger.kernel.org, Sascha Bischoff , Jonathan Cameron , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Steffen Eiden , Catalin Marinas , Will Deacon , Fuad Tabba , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1] KVM: arm64: vgic: Reset in_kernel on private IRQ allocation failure In-Reply-To: <20260802150845.3485757-1-fuad.tabba@linux.dev> References: <20260802150845.3485757-1-fuad.tabba@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/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: fuad.tabba@linux.dev, oupton@kernel.org, kvmarm@lists.linux.dev, stable@vger.kernel.org, Sascha.Bischoff@arm.com, jic23@kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, seiden@linux.ibm.com, catalin.marinas@arm.com, will@kernel.org, tabba@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@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 Sun, 02 Aug 2026 16:08:45 +0100, Fuad Tabba wrote: > > kvm_vgic_create() sets vgic.in_kernel before allocating the per-vCPU > private IRQs, but the allocation-failure path resets only vgic_model and > leaves in_kernel set. As irqchip_in_kernel() is !!in_kernel, the VM is > left with an in-kernel irqchip but no model, and the -EEXIST guard at the > top of kvm_vgic_create() rejects every retry, so userspace cannot recover > from a transient -ENOMEM. > > Reset in_kernel alongside vgic_model on the failure path. > > Fixes: 9435c1e1431003 ("KVM: arm64: gic: Set vgic_model before initing private IRQs") > Cc: stable@vger.kernel.org > Signed-off-by: Fuad Tabba > --- > arch/arm64/kvm/vgic/vgic-init.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c > index 907057881b26a..fdac6e24762da 100644 > --- a/arch/arm64/kvm/vgic/vgic-init.c > +++ b/arch/arm64/kvm/vgic/vgic-init.c > @@ -176,6 +176,7 @@ int kvm_vgic_create(struct kvm *kvm, u32 type) > } > > kvm->arch.vgic.vgic_model = 0; > + kvm->arch.vgic.in_kernel = false; > goto out_unlock; > } > > Acked-by: Marc Zyngier M. -- Jazz isn't dead. It just smells funny.