[PATCH v2] crypto: caam: use dma_alloc_coherent instead of dma_alloc

[Lucas Stach]

Am Mittwoch, den 12.07.2017, 06:40 +0200 schrieb Oleksij Rempel:
> It is a fixup for following patch:
> | commit ef4144b4ab6301d7417af3eb4d79cfc66bf0e731
> | Date:   Wed Mar 22 10:14:37 2017 +0100
> |
> |    crypto: caam - fix RNG buffer cache alignment
> 
> Signed-off-by: Oleksij Rempel <o.rempel at pengutronix.de>

Thanks. I've applied this patch with the commit message changed to the
following, to add a bit more information about the failure this is
fixing:

crypto: caam: use dma_alloc_coherent instead of dma_alloc

dma_alloc return non-coherent memory, but the driver does no cache
maintenance on the buffer, causing memory corruption. Fix this by
requesting coherent memory for the DMA transfer.

Fixes: ef4144b4ab63 (crypto: caam - fix RNG buffer cache alignment)

> ---
>  drivers/crypto/caam/caamrng.c | 4 +---
>  1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/crypto/caam/caamrng.c b/drivers/crypto/caam/caamrng.c
> index 31a92731d2..51c267e3d3 100644
> --- a/drivers/crypto/caam/caamrng.c
> +++ b/drivers/crypto/caam/caamrng.c
> @@ -203,8 +203,6 @@ static inline int rng_create_job_desc(struct caam_rng_ctx *ctx, int buf_id)
>  	init_job_desc_shared(desc, ctx->sh_desc_dma, sh_len, HDR_SHARE_DEFER |
>  			     HDR_REVERSE);
>  
> -	bd->addr = (dma_addr_t)bd->buf;
> -
>  	append_seq_out_ptr_intlen(desc, bd->addr, RN_BUF_SIZE, 0);
>  #ifdef DEBUG
>  	print_hex_dump(KERN_ERR, "rng job desc@: ", DUMP_PREFIX_OFFSET, 16, 4,
> @@ -218,7 +216,7 @@ static int caam_init_buf(struct caam_rng_ctx *ctx, int buf_id)
>  	struct buf_data *bd = &ctx->bufs[buf_id];
>  	int err;
>  
> -	bd->buf = dma_alloc(RN_BUF_SIZE);
> +	bd->buf = dma_alloc_coherent(RN_BUF_SIZE, &bd->addr);
>  
>  	err = rng_create_job_desc(ctx, buf_id);
>  	if (err)