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From: Aneesh Kumar K.V <aneesh.kumar@kernel.org>
To: Jason Gunthorpe <jgg@ziepe.ca>,
	Catalin Marinas <catalin.marinas@arm.com>
Cc: linux-coco@lists.linux.dev, kvmarm@lists.linux.dev,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, iommu@lists.linux.dev,
	Marc Zyngier <maz@kernel.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>,
	Steven Price <steven.price@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Thomas Gleixner <tglx@kernel.org>,
	Will Deacon <will@kernel.org>
Subject: Re: [PATCH v6 0/9] coco: guest: Enforce host page-size alignment
 for shared buffers
In-Reply-To: <20260918165754.GG11599@ziepe.ca>
References: <20260904103452.1197239-1-aneesh.kumar@kernel.org>
 <aq1sT2EDsGaomqST@arm.com> <20260918165754.GG11599@ziepe.ca>
Date: Wed, 23 Sep 2026 10:31:19 +0530
Message-ID: <yq5ao6do36jk.fsf@kernel.org>
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Jason Gunthorpe <jgg@ziepe.ca> writes:

> On Fri, Sep 18, 2026 at 05:52:31PM +0100, Catalin Marinas wrote:
>
>> TBH, I'm tempted not to support this configuration at all, just fail
>> gracefully if the realm page size doesn't match the host's. However, if
>> that's a real world configuration, 
>
> realm != host is going to be fairly common.
>
> host > realm is probably not that common, I would guess.
>

Wouldn't it be more common to run a distro with a 4K page size as the
guest on a custom hypervisor with a 4K or larger page size?

-aneesh