Re: [RFC PATCH v7 02/13] mm: Add an allocator for CoCo shared memory
From: Suzuki K Poulose <suzuki.poulose@arm.com>
Date: 2026-09-23 00:33:24
Also in:
dri-devel, kvmarm, linux-coco, linux-iommu, linux-media, linux-mm, lkml
On 22/09/2026 17:51, Jason Gunthorpe wrote:
On Tue, Sep 22, 2026 at 05:25:58PM +0100, Catalin Marinas wrote:quoted
Does the memset() post sharing logic work for pKVM as well? If nothing clears it, we have a small window where guest data is leaked to the host.Same question for RMM? Or did they define that the RMM zeros on these transitions?
RMM doesn't "define" what exactly is written when a granule is transitioned to "DELEGATED" or "UNDELEGATED". But does guarantee that the contents are wiped after the transition. This may be: * RMM writing random bytes or 0s * Changing the MEC of the location. See section A2.3.8 Granule wiping DEN0137 2.0-bet3 Cheers Suzuki