| From 412c98c1bef65fe7589f1300e93735d96130307c Mon Sep 17 00:00:00 2001 |
| From: Steve Cornelius <steve.cornelius@freescale.com> |
| Date: Mon, 15 Jun 2015 16:52:59 -0700 |
| Subject: crypto: caam - fix RNG buffer cache alignment |
| |
| From: Steve Cornelius <steve.cornelius@freescale.com> |
| |
| commit 412c98c1bef65fe7589f1300e93735d96130307c upstream. |
| |
| The hwrng output buffers (2) are cast inside of a a struct (caam_rng_ctx) |
| allocated in one DMA-tagged region. While the kernel's heap allocator |
| should place the overall struct on a cacheline aligned boundary, the 2 |
| buffers contained within may not necessarily align. Consenquently, the ends |
| of unaligned buffers may not fully flush, and if so, stale data will be left |
| behind, resulting in small repeating patterns. |
| |
| This fix aligns the buffers inside the struct. |
| |
| Note that not all of the data inside caam_rng_ctx necessarily needs to be |
| DMA-tagged, only the buffers themselves require this. However, a fix would |
| incur the expense of error-handling bloat in the case of allocation failure. |
| |
| Signed-off-by: Steve Cornelius <steve.cornelius@freescale.com> |
| Signed-off-by: Victoria Milhoan <vicki.milhoan@freescale.com> |
| Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/crypto/caam/caamrng.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/crypto/caam/caamrng.c |
| +++ b/drivers/crypto/caam/caamrng.c |
| @@ -56,7 +56,7 @@ |
| |
| /* Buffer, its dma address and lock */ |
| struct buf_data { |
| - u8 buf[RN_BUF_SIZE]; |
| + u8 buf[RN_BUF_SIZE] ____cacheline_aligned; |
| dma_addr_t addr; |
| struct completion filled; |
| u32 hw_desc[DESC_JOB_O_LEN]; |
