2021-02-04 16:31:22

by Arnd Bergmann

Subject: [PATCH] cwmwl8k: fix alignment constraints

From: Arnd Bergmann <[email protected]>

sturct mwl8k_dma_data contains a ieee80211_hdr structure, which is required to
have at least two byte alignment, and this conflicts with the __packed
attribute:

vers/net/wireless/marvell/mwl8k.c:811:1: warning: alignment 1 of 'struct mwl8k_dma_data' is less than 2 [-Wpacked-not-aligned]

Mark mwl8k_dma_data itself as having two-byte alignment to ensure the
inner structure is properly aligned.

Signed-off-by: Arnd Bergmann <[email protected]>
---
drivers/net/wireless/marvell/mwl8k.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/marvell/mwl8k.c b/drivers/net/wireless/marvell/mwl8k.c
index abf3b0233ccc..38eeab6369f7 100644
--- a/drivers/net/wireless/marvell/mwl8k.c
+++ b/drivers/net/wireless/marvell/mwl8k.c
@@ -808,7 +808,7 @@ struct mwl8k_dma_data {
__le16 fwlen;
struct ieee80211_hdr wh;
char data[];
-} __packed;
+} __packed __aligned(2);

/* Routines to add/remove DMA header from skb. */
static inline void mwl8k_remove_dma_header(struct sk_buff *skb, __le16 qos)
--
2.29.2

2021-02-08 11:29:56

by Kalle Valo

Subject: Re: mwl8k: fix alignment constraints

Arnd Bergmann <[email protected]> wrote:

> From: Arnd Bergmann <[email protected]>
>
> sturct mwl8k_dma_data contains a ieee80211_hdr structure, which is required to
> have at least two byte alignment, and this conflicts with the __packed
> attribute:
>
> vers/net/wireless/marvell/mwl8k.c:811:1: warning: alignment 1 of 'struct mwl8k_dma_data' is less than 2 [-Wpacked-not-aligned]
>
> Mark mwl8k_dma_data itself as having two-byte alignment to ensure the
> inner structure is properly aligned.
>
> Signed-off-by: Arnd Bergmann <[email protected]>

Patch applied to wireless-drivers-next.git, thanks.

bfdc4d7cbe57 mwl8k: fix alignment constraints

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches