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 04D7C37DAD5; Mon, 3 Aug 2026 23:14:08 +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=1785798852; cv=none; b=SfWY+DX0gE4g0XVBgxIAqs0diPpBkVfLQR9SHgDIRi4Pprx+Hs4HTdurC/iGCZo6i511KbeNc4u6qbu6Ja34GWYiWfygEDAHOf5mDh7/4Fa19jg9waAehJKuNxt/X9/yVERgEU5zzIq7EUl5cgx+JhvpXEW13TMWkwucQzHtdIU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785798852; c=relaxed/simple; bh=fG68MfhkwRfSg1W6YX0cbN8/yZcNS3S2f4yLKb+2+CU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=hFSq7VMm4/VyUKAOwX8jIODRQA3vizpSg+ee2/uFtWKDaVfGrdXRD+twakjyz0FE4df9KktEAPdaAxeik3rkdRmeMknTTJgtuaGxQixZFB4GWvUa1MxwcYH5uxmO7V2NcAwA3ZmZfeO54faDfBZrSTqgN2n4PmncJj+CExap2iw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AfNuvcWS; 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="AfNuvcWS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78DBD1F00A3E; Mon, 3 Aug 2026 23:14:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785798847; bh=fiugukty1Mn9VBap85XV+9U6g61CkNYwrAZccCYiZGU=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=AfNuvcWSdk4R6apsQH2JnDApmuBXbQg6asNwcqTyVS7BqpbXagvh7NbqDS307MA7x saoi64x4R1NGCFNK/bZbbIRg4oGJ9RCFMq5i1TCSGa2y6jmiPL1y90Lelj06uca1JX 0XkbsIRH7OR6Dj/sTcxBOCYPw5qsW2kOQ3X1VnxelCsxwEsdrxW/pSwUHMmByExxuz kmcNvs3TYj7nHn/0lxvaPGzOAD8vVbAb7vJfOk0QlNkXHzmbZ8lM4AW6mmRbSsqaLO 6zX7R1A2RjDc5vUvT9Rrf1I00Xn5bn6JaxfuQu02c0V+CBvcRk3xswBJULmi5MvFD3 5Pk2dKFtwEqvA== From: Mark Brown Date: Mon, 03 Aug 2026 23:56:52 +0100 Subject: [PATCH v18 07/14] KVM: arm64: Forward GCS exceptions to nested guests Precedence: bulk X-Mailing-List: linux-doc@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: <20260803-arm64-gcs-v18-7-fd8c40f5ad88@kernel.org> References: <20260803-arm64-gcs-v18-0-fd8c40f5ad88@kernel.org> In-Reply-To: <20260803-arm64-gcs-v18-0-fd8c40f5ad88@kernel.org> To: Catalin Marinas , Will Deacon , Marc Zyngier , Joey Gouly , Suzuki K Poulose , Shuah Khan , Fuad Tabba , Oliver Upton Cc: Peter Maydell , 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 0.16-dev X-Developer-Signature: v=1; a=openpgp-sha256; l=1286; i=broonie@kernel.org; h=from:subject:message-id; bh=fG68MfhkwRfSg1W6YX0cbN8/yZcNS3S2f4yLKb+2+CU=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBqcSCfDFrrJu6EBWatsQlkDL5fLdxzD6q+uZ194 xEX8/bZYV+JATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCanEgnwAKCRAk1otyXVSH 0P4eB/9zHfXUwqA3slkhU8zpWiO6oeFu2MR+OB2dN1p5kY4ZG138rVq10mYyWQU8QNQ6v1G0jpW In9wLKEM2acaBUUiCKckWBNkOJOlCGrneiptUyFmVfn5pmNv6S+KztRxd3gnCJODMFvftwMTFh6 FJ3CsmvV5hPa1G1Z5/KttX1zHQ/qsbBPkeNgmfmt1iAzurlgrSIKreSMTByopRgvu56croTYSik FBMaDy/0JcX9R9KdFmT+fV99wDcVF8BDhzFO5Zmz9I9bOuIxMQfmfEh2+0xULOvImlxQb/oPIw0 r05PfCDqy41xH/3wlnenzd6JxGRRauMN+CmPtGqR5toa2jxc 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. 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 54aedf93c78b..63dcc4a0e69a 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