From 8c2a029c7eff14510fed04cef2848c6d21ed92dd Mon Sep 17 00:00:00 2001 From: Jacob Keller Date: Mon, 9 Nov 2015 14:04:08 -0800 Subject: [PATCH] fm10k: correctly pack TLV structures and explain reasoning The TLV format for little endian structures is actually 4 byte aligned copy. To this end, we need to add an additional __aligned(4) marker along with __packed to ensure that these structures are actually 4 byte aligned and packed correctly. Use of just __packed will not work as this will result in 1byte alignment which is incorrect. Add a comment explaining the reasoning behind why these structures need the special treatment. Signed-off-by: Jacob Keller Tested-by: Krishneil Singh Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/fm10k/fm10k_pf.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/intel/fm10k/fm10k_pf.h b/drivers/net/ethernet/intel/fm10k/fm10k_pf.h index a8fc512..3378592 100644 --- a/drivers/net/ethernet/intel/fm10k/fm10k_pf.h +++ b/drivers/net/ethernet/intel/fm10k/fm10k_pf.h @@ -74,6 +74,11 @@ enum fm10k_pf_tlv_attr_id_v1 { #define FM10K_MSG_UPDATE_PVID_PVID_SHIFT 16 #define FM10K_MSG_UPDATE_PVID_PVID_SIZE 16 +/* The following data structures are overlayed directly onto TLV mailbox + * messages, and must not break 4 byte alignment. Ensure the structures line + * up correctly as per their TLV definition. + */ + struct fm10k_mac_update { __le32 mac_lower; __le16 mac_upper; @@ -81,26 +86,26 @@ struct fm10k_mac_update { __le16 glort; u8 flags; u8 action; -} __packed; +} __aligned(4) __packed; struct fm10k_global_table_data { __le32 used; __le32 avail; -} __packed; +} __aligned(4) __packed; struct fm10k_swapi_error { __le32 status; struct fm10k_global_table_data mac; struct fm10k_global_table_data nexthop; struct fm10k_global_table_data ffu; -} __packed; +} __aligned(4) __packed; struct fm10k_swapi_1588_timestamp { __le64 egress; __le64 ingress; __le16 dglort; __le16 sglort; -} __packed; +} __aligned(4) __packed; s32 fm10k_msg_lport_map_pf(struct fm10k_hw *, u32 **, struct fm10k_mbx_info *); extern const struct fm10k_tlv_attr fm10k_lport_map_msg_attr[]; -- 2.7.4