[PATCH 5/6] crypto: eip93: order result descriptor reads after PE_READY
From: Jihong Min
Date: Sun May 24 2026 - 15:50:38 EST
The result handler polls ownership bits until the packet engine reports the
descriptor as ready. Ensure later descriptor reads observe the DMA writes
that completed before PE_READY became visible.
Use the value already read from the descriptor for error parsing.
Fixes: 9739f5f93b78 ("crypto: eip93 - Add Inside Secure SafeXcel EIP-93 crypto engine support")
Reported-by: Benjamin Larsson <benjamin.larsson@xxxxxxxxxx>
Suggested-by: Benjamin Larsson <benjamin.larsson@xxxxxxxxxx>
Assisted-by: Codex:gpt-5.5
Signed-off-by: Jihong Min <hurryman2212@xxxxxxxxx>
---
drivers/crypto/inside-secure/eip93/eip93-main.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/crypto/inside-secure/eip93/eip93-main.c b/drivers/crypto/inside-secure/eip93/eip93-main.c
index 276839e1a515..e3bd28cc0c67 100644
--- a/drivers/crypto/inside-secure/eip93/eip93-main.c
+++ b/drivers/crypto/inside-secure/eip93/eip93-main.c
@@ -224,11 +224,14 @@ static void eip93_handle_result_descriptor(struct eip93_device *eip93)
FIELD_GET(EIP93_PE_LENGTH_HOST_PE_READY, pe_length) !=
EIP93_PE_LENGTH_PE_READY);
- err = rdesc->pe_ctrl_stat_word & (EIP93_PE_CTRL_PE_EXT_ERR_CODE |
- EIP93_PE_CTRL_PE_EXT_ERR |
- EIP93_PE_CTRL_PE_SEQNUM_ERR |
- EIP93_PE_CTRL_PE_PAD_ERR |
- EIP93_PE_CTRL_PE_AUTH_ERR);
+ /* Order descriptor reads after device ownership is returned. */
+ dma_rmb();
+
+ err = pe_ctrl_stat & (EIP93_PE_CTRL_PE_EXT_ERR_CODE |
+ EIP93_PE_CTRL_PE_EXT_ERR |
+ EIP93_PE_CTRL_PE_SEQNUM_ERR |
+ EIP93_PE_CTRL_PE_PAD_ERR |
+ EIP93_PE_CTRL_PE_AUTH_ERR);
desc_flags = FIELD_GET(EIP93_PE_USER_ID_DESC_FLAGS, rdesc->user_id);
crypto_idr = FIELD_GET(EIP93_PE_USER_ID_CRYPTO_IDR, rdesc->user_id);
--
2.53.0