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 908AB35C1BC; Wed, 1 Jul 2026 23:23:23 +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=1782948204; cv=none; b=c4Qp0153C8tmD6LBlAduMQaDMucuBKAv3n/5VBhy0KuO5twL7+l4R/OUe5ImM/pocLTv54ouXCqzzqzCu6CBzYT4LqlGgNjeFyXohzGrnOEfHvGsjnDjkicxxoseb8zT/HIgoUl5M6ubCuovp5zcVtPbS5zWRX8Xc/g2RhTFfT8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782948204; c=relaxed/simple; bh=csNuts0IzkGAc0W7bjedWikPnGB16Sv5nPR4GQNaV5o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=i4dfAl9B9kpcX1CunpDfkfs8EUEzFArTSzS85aC0sDKpIYpw/zD2tgbFaEMgDFwlOsaidfEJIZ0V0JWIhg4+aWrZuyl6MPxWmCwhM1anBeWiVWBd2Dw5ymSEYTqe4fn+Jy7HKuXoWhHeXkuee9nt2SAC0DZ5eCsxntMDrhZjJ+w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aYWMuWjT; 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="aYWMuWjT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 076651F000E9; Wed, 1 Jul 2026 23:23:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782948203; bh=hiKmqO0wNrjJu7zzb5rGyi5QeG0KP1hAbxpV1oyAAlE=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=aYWMuWjTlBwaME+x1eFSgn+qz2xUyBupMvSmK+RxOlCo3VhCvVTCNWw7Pbhta2G6S vhnTm9ONyh2F7530Zd9GZFgrHkTBNbUCSJGVfe3bgnOTyXL746UtovbEKzL8cp8YBl DNp8gCYtzVL2yrbTy0lFZFUUlzncCkOK9l2wTKQvXOUaEK8Qc7bXze/znzBF/y/0Hy akIizP07KoORUuOhhkQJ6gfRSon37f7Q7oAJdHu0F7xuAFQajfGpzVXsbaxyWt0sTU v3GnLxXouW6CcrzBBZ2YUnGAWiBNO8XJYP3y/qWbFwsy1PN1U2ugbp7URnBPcGdnEv Hw9JJ4NdkGRZg== Date: Wed, 1 Jul 2026 16:23:21 -0700 From: Oliver Upton To: Colton Lewis Cc: stable@vger.kernel.org, Catalin Marinas , Will Deacon , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Zenghui Yu , Mingwei Zhang , linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/5] Backport ARM64 VHE boot fixes to 6.6.y Message-ID: References: <20260701204342.2654385-1-coltonlewis@google.com> 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=us-ascii Content-Disposition: inline In-Reply-To: <20260701204342.2654385-1-coltonlewis@google.com> The subject prefix should be "[PATCH 6.6 0/5]" so people know right up front where this is going. On Wed, Jul 01, 2026 at 08:43:37PM +0000, Colton Lewis wrote: > This series backports VHE CPU boot fixes to the 6.6.y stable branch. > > These fixes are already present in the 6.12.y stable branch (and > newer), but are missing in 6.6.y. They are required to enable booting > L1 guests with nested virtualization enabled (kvm-arm.mode=nested). It's a bit worse than this. The architecture retroactively made FEAT_E2H0 an optional feature, there are now implementations in the wild that do not support the feature. > Without these patches, a 6.6.y guest boots with HCR_EL2.E2H > incorrectly configured (because it misses VHE-only detection or early > initialization), causing early boot hangs/trap loops. > > Conflict resolutions: > - Patch 4 (KVM: arm64: Initialize HCR_EL2.E2H early) had conflicts in > arch/arm64/kvm/hyp/nvhe/hyp-init.S due to differences in state > initialization. Resolved by extracting EL2 state initialization into > __kvm_init_el2_state. > - Patch 5 (arm64: Revamp HCR_EL2.E2H RES1 detection) had conflicts in > arch/arm64/include/asm/el2_setup.h. Resolved by using raw msr hcr_el2 > instead of the missing msr_hcr_el2 macro. > > > Marc Zyngier (4): > arm64: sysreg: Add layout for ID_AA64MMFR4_EL1 > arm64: Treat HCR_EL2.E2H as RES1 when ID_AA64MMFR4_EL1.E2H0 is > negative > arm64: Fix early handling of FEAT_E2H0 not being implemented > arm64: Revamp HCR_EL2.E2H RES1 detection > > Mark Rutland (1): > KVM: arm64: Initialize HCR_EL2.E2H early > > arch/arm64/include/asm/el2_setup.h | 52 ++++++++++++++++++++++++++++++ > arch/arm64/kernel/head.S | 17 +++------- > arch/arm64/kvm/hyp/nvhe/hyp-init.S | 16 +++++++-- > arch/arm64/tools/sysreg | 37 +++++++++++++++++++++ > 4 files changed, 107 insertions(+), 15 deletions(-) > > > base-commit: d1cfde2d5d15be14123bdd1689162bd27f995a90 > -- > 2.55.0.rc2.803.g1fd1e6609c-goog >