RE: [PATCH v5 2/3] mmc: block: register RPMB partition with the RPMB subsystem

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Is it possible that idata->buf is not DMA capable? Any other ideas?

Thanks for testing. I don't know, the idata->buf is allocated using alloc_pages_exact(nr_pages * PAGE_SIZE, GFP_KERNEL | __GFP_ZERO); in optee_pool_op_alloc_helper().

Is this really true for idata->buf or isnt the complete RPMB frame memory allocated like this and therefore idata->buf not page aligned?

You're right.

Maybe add an assert of PAGE_ALIGNED(idata->buf)?

Thanks, Avri

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For RPMB via tee-supplicant the idata->buf is allocated within memdup_user and therefore page aligned.

Yes, that's a difference. Have you tested with page-aligned buffers to see if it helps?