From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E60ADC43458 for ; Wed, 1 Jul 2026 23:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=hiKmqO0wNrjJu7zzb5rGyi5QeG0KP1hAbxpV1oyAAlE=; b=CW10nEDa1Y2CBJk/i8+AWKm7l9 +zLt7VzMpPOEZxJohmTY3bs/aStQyVv8W7tNfmY4FCiQv14/UajB5fsHB817r0P63ukCVnhXgmKcP 8iT/9Ehcq2Kb0JKszgNUTSV2X7zPMnfbxm64JDJHByATPZnI2tGQbZgzbmkMur+TPnfSMDypiuJWw fjYL3ajEiGsVc9AFVhLYVjNIuRQ3sopnDJfo8quATRiZsoLCJa2Tgiy3Sk4gDCPfVJJy9wJL3dpXi QokpANqstwqBdYPJY0EBqVnFm9gFKKljf2FP5i36jnu0IRXLkEGA23ZFvVu3mRtdaf2MO6EJBP2zD lle5NI2g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wf4H7-000000038xE-14Fl; Wed, 01 Jul 2026 23:23:25 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wf4H5-000000038x5-3gB1 for linux-arm-kernel@lists.infradead.org; Wed, 01 Jul 2026 23:23:23 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 4BE1343241; Wed, 1 Jul 2026 23:23:23 +0000 (UTC) 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260701204342.2654385-1-coltonlewis@google.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 >