Messages in this thread | | | Date | Wed, 31 Aug 2022 08:57:05 +0800 | Subject | Re: [PATCH 2/2] iommu: Use the user PGD for SVA if PTI is enabled | From | Baolu Lu <> |
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On 8/23/22 4:12 AM, Jacob Pan wrote: > With page table isolation, the kernel manages two sets of page tables > for each process: one for user one for kernel. When enabling SVA, the > current x86 IOMMU drivers bind device and PASID with the kernel copy > of the process page table. > > While there is no known "Meltdown" type of DMA attack, exposing > kernel mapping to DMA intended for userspace makes the system vulnerable > unnecessarily. It also breaks the intention of PTI. > > This patch replaces kernel page table PGD with the user counterpart, > thus fulfill the promise of PTI on the DMA side. > > Signed-off-by: Jacob Pan<jacob.jun.pan@linux.intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Best regards, baolu
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