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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, 19 Nov 2020 at 15:39, Steven Price wrote: > This series adds support for Arm's Memory Tagging Extension (MTE) to > KVM, allowing KVM guests to make use of it. This builds on the existing > user space support already in v5.10-rc1, see [1] for an overview. > The change to require the VMM to map all guest memory PROT_MTE is > significant as it means that the VMM has to deal with the MTE tags even > if it doesn't care about them (e.g. for virtual devices or if the VMM > doesn't support migration). Also unfortunately because the VMM can > change the memory layout at any time the check for PROT_MTE/VM_MTE has > to be done very late (at the point of faulting pages into stage 2). I'm a bit dubious about requring the VMM to map the guest memory PROT_MTE unless somebody's done at least a sketch of the design for how this would work on the QEMU side. Currently QEMU just assumes the guest memory is guest memory and it can access it without special precautions... thanks -- PMM _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel