[PATCH 1/6] wifi: ath10k: use flexible array in struct wmi_host_mem_chunks

From: Jeff Johnson
Date: Wed Dec 13 2023 - 12:07:35 EST


Currently struct wmi_host_mem_chunks defines:
struct host_memory_chunk items[1];

Per the guidance in [1] this should be a flexible array. However there
is a documented requirement:
some fw revisions require at least 1 chunk regardless of count

To satisfy this requirement, follow the guidance from [2] and wrap the
array in a union which contains both the flexible array and a single
instance of the underlying struct. Since the footprint of the struct
is unchanged, no additional driver changes are required.

No functional changes, compile tested only.

[1] https://docs.kernel.org/process/deprecated.html#zero-length-and-one-element-arrays
[2] https://lore.kernel.org/linux-wireless/202308301529.AC90A9EF98@keescook/

Signed-off-by: Jeff Johnson <quic_jjohnson@xxxxxxxxxxx>
---
drivers/net/wireless/ath/ath10k/wmi.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath10k/wmi.h b/drivers/net/wireless/ath/ath10k/wmi.h
index 9146df98fcee..833ce0251a2c 100644
--- a/drivers/net/wireless/ath/ath10k/wmi.h
+++ b/drivers/net/wireless/ath/ath10k/wmi.h
@@ -3069,7 +3069,10 @@ struct host_memory_chunk {
struct wmi_host_mem_chunks {
__le32 count;
/* some fw revisions require at least 1 chunk regardless of count */
- struct host_memory_chunk items[1];
+ union {
+ struct host_memory_chunk item;
+ DECLARE_FLEX_ARRAY(struct host_memory_chunk, items);
+ };
} __packed;

struct wmi_init_cmd {

--
2.42.0