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Re: [RFC PATCH kernel 10/17] x86, dma: Allow accepted devices to map private memory
- To: Alexey Kardashevskiy <aik@xxxxxxx>
- From: Jason Gunthorpe <jgg@xxxxxxxx>
- Date: Wed, 16 Sep 2026 09:48:49 -0300
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- Delivery-date: Wed, 16 Sep 2026 12:48:59 +0000
- List-id: Xen developer discussion <xen-devel.lists.xenproject.org>
On Wed, Sep 16, 2026 at 09:51:50PM +1000, Alexey Kardashevskiy wrote:
> bool force_dma_unencrypted(struct device *dev)
> {
> /*
> - * For SEV, all DMA must be to unencrypted addresses.
> + * Require unencrypted DMA unless the device has been "accepted",
> + * enabled by a TSM driver to DMA to private encrypted memory.
> */
> if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT))
> - return true;
> + return !__device_cc_accepted(dev);
I want this out of arch code, after Aneesh's recent rework Nicolin is trying
this approach:
https://lore.kernel.org/all/abddd433493324a6bfdf8ba9710e96d90f0d1ccc.1789010941.git.nicolinc@xxxxxxxxxx/
Jason
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