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Date: Thu, 2 Jul 2026 08:16:05 +0200
From: Greg KH <gregkh@linuxfoundation.org>
To: Colton Lewis <coltonlewis@google.com>
Cc: stable@vger.kernel.org, Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>, Marc Zyngier <maz@kernel.org>,
	Oliver Upton <oliver.upton@linux.dev>,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Zenghui Yu <yuzenghui@huawei.com>,
	Mingwei Zhang <mizhang@google.com>,
	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: <2026070224-small-apprehend-b71b@gregkh>
References: <20260701204342.2654385-1-coltonlewis@google.com>
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In-Reply-To: <20260701204342.2654385-1-coltonlewis@google.com>

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).
> 
> 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.

Why is this needed for 6.6.y?  Why not just use 6.12.y and newer for
systems that require this new feature?  What is preventing that from
happening?

thanks,

greg k-h