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 50D023806AD; Tue, 1 Sep 2026 21:51:02 +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=1788299463; cv=none; b=twAQdhV+r7JeG9UvK6FzNji5j2BQ1M/uTfZ2EiDl9iE9biqQ42/lzjL/yMKLy1cnov0rh2lnkBBCe5lunPUNrgf8IefSLrnVCc2P7NgHYCwu+ub+5EXRPT83Gd2CjJ1IunWA381dnf1as8J8eI5jtMMmonpb/ldpTRIKo+vx/40= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788299463; c=relaxed/simple; bh=ybZ3Kdn/7X6FtbChfk8rW3p585sYuKBjGuFuBHbmNzA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=H28721i7HP+S6UHnw6trj91eclY1njmvBijeVtSZ6eV4muD8fmxeA+WMkJ48pt6RBU1JaGbMKjvHDl/B1isvhVGeVvMUzn+asRlVjV4QE5BZckTd4sKbzigr25zannSPc+DUVramj9+oxRTvURtfmhC7K/5NS/YGAM+uLG3ZZuk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AQHj1ZT2; 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="AQHj1ZT2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AF4FB1F00A3D; Tue, 1 Sep 2026 21:50:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788299461; bh=fRndjmqR/pDKaAT5YJWoMzUu6Phwwq9DvX5GRxKta6o=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=AQHj1ZT2mBNjscrSoVJTdOUjme+Hwc1l7GuTPF/1IPpm8ESshRDsUVq+lnWn+6RRe /4Asky7NXAGXyh9Np9ke1b7ckqGzxcpdy8a0gvGK8hUVZfO/rWz0ON/b83Pv9OghCA D4xEX2lbDsV/505DqX0qTJ0oU3hEAg8hisS4Bq3y3m/zmAHbMMjBEYZUItgHjJcwXv 4v82zRU99OaGK/vpHzARBDPTSxr0cyreid8gVVsolZYxhy2PPwW5fDWehCiWe6bCd8 6iOqjuNkVTLI+Gt1/pAgrpUrjUeJ9gUpUeWHoUKXxZlyTjdCmdLktZEgEvSrOVXfO/ 93hgqF0i64PoQ== From: Mark Brown Date: Tue, 01 Sep 2026 22:47:05 +0100 Subject: [PATCH v20 07/14] 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: <20260901-arm64-gcs-v20-7-f31750bdfadb@kernel.org> References: <20260901-arm64-gcs-v20-0-f31750bdfadb@kernel.org> In-Reply-To: <20260901-arm64-gcs-v20-0-f31750bdfadb@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=1286; i=broonie@kernel.org; h=from:subject:message-id; bh=ybZ3Kdn/7X6FtbChfk8rW3p585sYuKBjGuFuBHbmNzA=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBql0ih715I7fTQ8ImR5pPuXiL5bjJV6Yt6xQaij m17Hr7PAbCJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCapdIoQAKCRAk1otyXVSH 0DAfB/9WzE5SnoA6xrOiQ6faxAotAUN5O1BpWGY3P1Q3uA8gLLr83/moWCnFRRb9cYMAaiKck+T jZUpsFk1gtgdF7SiIrcCbRgPv5l144hBm/Fc8KKEpuS7p2WmNg3O6YN7+x1PXZULD1vxkKAyLS+ L3iDSWXv4Ytu8SLiczzTC81ioPGMyqLMblIJQ/YBpzZMxN8+4lqAf4nkqxWwBLe+L6LExTl+Oj8 +ZmmzqRYFl9iruvA4K+jpOWzhh2gmbgo9V/ERWPSeU5HoZxqY5dcR7o696C3IX1PENQwejk9tJa VYzH1wzs1ALlnoUrGMldITlNim0Ml+jCZFc0rUE0vhWCNBwl 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 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