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 A0E9452189B; Wed, 30 Sep 2026 21:49:20 +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=1790804961; cv=none; b=lWXa82QvSiMO/JdKUgF415dUuLLOkV7zx1hoIu3DxMsCFSONuhuTzHTy8X4HKjF24aXB9ouzHfBI323wpxWpnEiRsHuokmZw0UoKLucQizdPZaU9syab0XW7DdcqdYGllfCK34MwgJCbyfv4HT+ATvlXU9powXIg/rzmSMrGA8Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790804961; c=relaxed/simple; bh=kVbReCZrKoi+cVaC6OJWcE+twh1TXQHikn7eWoOdtvk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=AHILXvAdJEQhWiBMGL/zRyIF9buklTOi4PcFa+E2cT0TdSM0E2+ZcxY67I6SU1T7oMGeHC69uDM1FrQrgXWSKnCwQv3H/q2a/MsJggP2Zk4RrTY3CViyCiSXt1+gy4aqymm6EaetMcgwB3lCYBsikygQEL/uW6Sh8BefEzMrGfI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ts8bHGm2; 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="Ts8bHGm2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C94C1F000FF; Wed, 30 Sep 2026 21:49:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790804960; bh=ETO//ZHEIrAWcvZFpQcrmAKGm+pliNn3pzbd4bW/wbA=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=Ts8bHGm29D1eMA1ta/GX1aqLyyVAi8ruqECban51kmGbRcRgDMsWBcCDAl0t2f3Jh Q/jLdqjBnV+OEHiSbInjqDYJW3odZYvT11P1QpbunBu4HFg50GGd3PsnO/OJfHwjv1 cyr+X5i7pYq83Sj6UiV09wpQGnCKVhSv/jpvOH2KXXxkPqugXlyJtbHWmiA1YUapYd C2EPaZNy7XsHTcCZ3Oox0e1+FjyzInMk0f1opkKPGNIiXuqHaBK2Tqu1IibKtTBVaX 9XAlCbwpAzGbtk85ULfPQlGSBOguDVYMq/Be6o9croqMZ800dQpGmf9w//yIU3XOy9 3b9kjxhA7fITg== From: Mark Brown Date: Wed, 30 Sep 2026 22:48:17 +0100 Subject: [PATCH v21 07/15] KVM: arm64: Forward GCS exceptions to nested guests Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260930-arm64-gcs-v21-7-3556644cd927@kernel.org> References: <20260930-arm64-gcs-v21-0-3556644cd927@kernel.org> In-Reply-To: <20260930-arm64-gcs-v21-0-3556644cd927@kernel.org> To: Catalin Marinas , Will Deacon , Marc Zyngier , Joey Gouly , Suzuki K Poulose , Shuah Khan , Oliver Upton , Fuad Tabba Cc: Peter Maydell , Leonardo Bras , Wei-Lin Chang , Yao Yuan , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Mark Brown X-Mailer: b4 0.17-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=1333; i=broonie@kernel.org; h=from:subject:message-id; bh=kVbReCZrKoi+cVaC6OJWcE+twh1TXQHikn7eWoOdtvk=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBqvYO4QbfvLeVqTJpjsPJjc0EbJR8LurVnuvWMa bAxPXZiG5WJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCar2DuAAKCRAk1otyXVSH 0EzLB/0X4o5J+Ob3x2kpC8lQ8ERNBXCpJ05jLcfpiazZPwXlKoGWfNoYBN6W1t/+QdQX/pWmMvF 4/9rpQcNiHT8J3tHlFJ0/BsGvEmP3SdsYdVt12wgekEypSAgwPZ72VrzfW/nJlE+yhMTP2xP0o8 oXzZxyDkTKHz7fihVqNfygtcv1cRcJvyq8c68xHosJaj+3rBUjswzk1DzJ4NHXa6MxNq8PhySPa UAJx7D4ehMg6Rbwgp723DbbbjdIBKGqwnkv6JtNYCGl5oyDvLaBUEWRM83zap9K9hxNsmoTc48p 0/+lkUNYaRVU7dj9yWoo1LGKSQPHFWoTouPxFugwWMtXMgZm X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB For nested guests where HFGITR_EL2.nGCSSTR_EL1 is clear or when there are L2 GCS data check exceptions we need to forward the exception to the guest. Add handling to do so. Reviewed-by: Leonardo Bras Signed-off-by: Mark Brown --- arch/arm64/kvm/handle_exit.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c index db37678dcb05..a8198e96fcb4 100644 --- a/arch/arm64/kvm/handle_exit.c +++ b/arch/arm64/kvm/handle_exit.c @@ -304,12 +304,24 @@ static int handle_svc(struct kvm_vcpu *vcpu) return 1; } +/* + * We might get GCS exceptions that need to be forwarded to the + * hypervisor when a nested guest has HFGITR_EL2.nGCSSTR_EL1 clear, or + * for a GCS data check exception for a L2 guest. + */ static int kvm_handle_gcs(struct kvm_vcpu *vcpu) { - /* We don't expect GCS, so treat it with contempt */ - if (kvm_has_feat(vcpu->kvm, ID_AA64PFR1_EL1, GCS, IMP)) - WARN_ON_ONCE(1); + if (!kvm_has_gcs(vcpu->kvm)) { + kvm_inject_undefined(vcpu); + return 1; + } + if (vcpu_has_nv(vcpu)) { + kvm_inject_nested_sync(vcpu, kvm_vcpu_get_esr(vcpu)); + return 1; + } + + WARN_ON_ONCE(1); kvm_inject_undefined(vcpu); return 1; } -- 2.47.3