On Sun, Mar 01, 2020 at 04:05:23PM -0800, David Rientjes wrote: > When AMD memory encryption is enabled, all non-blocking DMA allocations > must originate from the atomic pools depending on the device and the gfp > mask of the allocation. > > Keep all memory in these pools unencrypted. > > Signed-off-by: David Rientjes <[email protected]> > --- > arch/x86/Kconfig | 1 + > kernel/dma/direct.c | 9 ++++----- > kernel/dma/remap.c | 2 ++ > 3 files changed, 7 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -1523,6 +1523,7 @@ config X86_CPA_STATISTICS > config AMD_MEM_ENCRYPT > bool "AMD Secure Memory Encryption (SME) support" > depends on X86_64 && CPU_SUP_AMD > + select DMA_DIRECT_REMAP
I think we need to split the pool from remapping so that we don't drag in the remap code for x86. > if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && > - dma_alloc_need_uncached(dev, attrs) && We still need a check here for either uncached or memory encryption. > @@ -141,6 +142,7 @@ static int atomic_pool_expand(struct gen_pool *pool, > size_t pool_size, > if (!addr) > goto free_page; > > + set_memory_decrypted((unsigned long)page_to_virt(page), nr_pages); This probably warrants a comment. Also I think the infrastructure changes should be split from the x86 wire up. _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
