Messages in this thread | | | Date | Wed, 30 Mar 2022 21:08:43 -0700 | From | Christoph Hellwig <> | Subject | Re: "dma-mapping: remove CONFIG_DMA_REMAP" causes AMD SME boot fail |
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On Wed, Mar 30, 2022 at 03:17:20PM -0400, Alex Xu (Hello71) wrote: > Excerpts from Christoph Hellwig's message of March 30, 2022 2:01 pm: > > Can you try this patch, which is a bit of a hack? > > > > diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c > > index 50d209939c66c..61997c2ee0a17 100644 > > --- a/arch/x86/mm/mem_encrypt.c > > +++ b/arch/x86/mm/mem_encrypt.c > > @@ -28,7 +28,8 @@ bool force_dma_unencrypted(struct device *dev) > > * device does not support DMA to addresses that include the > > * encryption mask. > > */ > > - if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) { > > + if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT) && > > + !get_dma_ops(dev)) { > > u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask)); > > u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask, > > dev->bus_dma_limit); > > > > This seems to work for me.
Ok, I'll try to come up with a less hacky version and will start a discussion with the AMD folks that know memory encryption better. Thanks for the report and testing already!
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