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 5B13542C506; Fri, 31 Jul 2026 12:37:54 +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=1785501476; cv=none; b=gi41xnaKOblPr4b3YLPBoetExwhZiBtcvXVHuJsXEK+IQQfKTOtVVWUOqQsiSS07dTLb1xj5BRfMadVQHUBHJ02rDCUPl/qWUuw6p720iafayjQhf1uQnJ59UluG2ab1qwr+rGgItXq/9JJ2slPYrl22GBg96680nyyFd+bOsEE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785501476; c=relaxed/simple; bh=rDHWQQxEJuusHon3I+fAxB9MIrb5YJQCMI7dak6KWEg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=cN6qbHjJI+JYRDWrFGK3jdnFSaE6sgRZg1kim5Q3cOdzZeTEDZJUb6P0NfBxfchqa5eZVofpvg8HtJxiK55DWMwuNMO7IHSslKtBflAxKSJ61dk1nCEYHo691T4koFsJB/PUQWWFl4iFdrKNRkWgnvqbqMwCNueqJFjm/W69zKI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iJqGMowA; 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="iJqGMowA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5579B1F00A3A; Fri, 31 Jul 2026 12:37:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785501473; bh=zCJHK0SeIvlWzxabLhFPeGESfHTjKksGVicGWZCTv30=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=iJqGMowAboxmy1P5IlGaEE38NkRkPK7mKjio3DeTheegYBbVYE32ZnIE4mZHqkZVo 1UAGyNaLpWiqYKNmHeZN0msfw4MM53eZbvOlew1MC2Kd/KKq6g23MhFArAc+U59MwN YtHg/S0UwnP6Mah6Jelm6TvE9XKyfS+Fzy5AAunq9bzSdp4Q7bYN0gwbBKMMwfsWMn Ka1alk8dxyUhg1c4y+BJ5RiXzEqUHdlidLBZqOyJEDZzYprmPEeJXEajRIatG4FRsX +NYMhuuGDKO+NFKWAbccYFy20Y26lk6jgJKbnqKKW639MdDlb2eJL3WZR/ZGepRx/a 97WQ5YcOiLQ3g== From: Mark Brown Date: Fri, 31 Jul 2026 13:25:45 +0100 Subject: [PATCH v17 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: <20260731-arm64-gcs-v17-7-5e39ca01b14e@kernel.org> References: <20260731-arm64-gcs-v17-0-5e39ca01b14e@kernel.org> In-Reply-To: <20260731-arm64-gcs-v17-0-5e39ca01b14e@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=1289; i=broonie@kernel.org; h=from:subject:message-id; bh=rDHWQQxEJuusHon3I+fAxB9MIrb5YJQCMI7dak6KWEg=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBqbJcB2ZA4mYrU3T/oePkXT6loWodvKV1DXz/et D9sDVptYMmJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCamyXAQAKCRAk1otyXVSH 0NAtB/9rnnOR9pvvQytmU3HdeTpEdsReccrj1uWh0UJsc6rW9zLJOLGb2VNHYuNUslndlYG4Dxj sWhuSHo97JuPjxX/XFC4+uI1RRshl4SjGMlqGiI2s9nR6fTXw6IlWPsMxZ6Cyc334lyv3GHI1uH 5Mk7hxCTN3cqE8jvR+UPz50Ps5tBpFY0BtmdOjDZErI4UtwciU7k28j9NZHZVlNQawo2yOi5k+K xkvTAbjc6vGsyvfp4b8ovc68w+je2bX9WmCC6rv/x0iAhpz3x4uGjH8U8si5dbV6RXVAjv8pHPY L5paL5Yu5Grga6aziC8Gt77jvMaN98BaNIxr1kHZMY06ny7J 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..9db350891793 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 (is_nested_ctxt(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