From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CDD84377577; Tue, 17 Feb 2026 20:11:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771359061; cv=none; b=JaQzPJWhQo1EIBEWTgevXaVelOCtzDHwHftrMJeSqsTwgw3ZvVhirAfg8aCfzPcKJPIAGcAgI7CPBz9aK8JNY6lQnRzIW0pN6PYlEfD5khOk8dOtSm4gkMUFDzrXk7udBuX0gvusN5kKTBx8/pj1V1ixp3bnGQQNhRIDS5NMtDs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771359061; c=relaxed/simple; bh=ONjWETjeIq0uvNNrNs6VZfuywvsVa18zXJLtFUJ/lX4=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=MxY9DiaCpoTLFOG4eanCPv4wQQz+a25tOaNVW3U7IdG0cpy38pp3Km4Va1OYrswqsoZfdjcA+W6AGTz2RVtheRixQr94ZMUlwXvbqweGrFJlqdwP8NcWQqkNWL6XckBzGUgV8SMfarOV9ycgZ5G6ymvtRov/pX9UStE0hHuelVE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vOEC81JN; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="vOEC81JN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 99611C4CEF7; Tue, 17 Feb 2026 20:11:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771359061; bh=ONjWETjeIq0uvNNrNs6VZfuywvsVa18zXJLtFUJ/lX4=; h=Date:From:To:Cc:Subject:From; b=vOEC81JNzZN35/gTX96e3pupgvf/2Aw4xk4X/DcYQO9Igd8qv3zFQ8kVD0vRkU2bB 33O0F45EvhQ2PrZUvfqItKaP/f/2XIRC6t9OYSpuGfekWcJTkTpWIEolCltHdigWPr 5ep9WEe35v+zGX5t5Nv40lVoMAGGW67frt2mC+P3vTzqquhSmIXldEMVviOVGYWiOX 50OWrCPN/0aLf9WkpLaS1OucgcRINEvbB8wrXtJNg6kxRDr7yYW35DvzFLjTcXuUBz YXBVRu9Cg6X9YJPB9UuchFIHebcp8+RWS0BfS1U2Mr0tCmkERVkQ8L2PhUxEdvZiRD q4lPlJgRxKYEw== Date: Tue, 17 Feb 2026 14:10:28 +0900 From: "Gustavo A. R. Silva" To: Jeff Johnson , Kalle Valo Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org Subject: [PATCH v2][next] wifi: ath6kl: wmi: Avoid -Wflex-array-member-not-at-end warning Message-ID: Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. struct bss_bias_info is a flexible structure, this is a structure that contains a flexible-array member (struct bss_bias bss_bias[]). Since struct roam_ctrl_cmd is defined by hardware, we create the new struct bss_bias_info_hdr type, and use it to replace the object type causing trouble in struct roam_ctrl_cmd, namely struct bss_bias_info. Also, once -fms-extensions is enabled, we can use transparent struct members in struct bss_bias_info. Notice that the newly created type does not contain the flex-array member `bss_bias`, which is the object causing the -Wfamnae warning. After these changes, the size of struct roam_ctrl_cmd, along with its member's offsets remain the same, hence the memory layout doesn't change: Before changes: struct roam_ctrl_cmd { union { u8 bssid[6]; /* 0 6 */ u8 roam_mode; /* 0 1 */ struct bss_bias_info bss; /* 0 1 */ struct low_rssi_scan_params params; /* 0 8 */ } info; /* 0 8 */ u8 roam_ctrl; /* 8 1 */ /* size: 9, cachelines: 1, members: 2 */ /* last cacheline: 9 bytes */ } __attribute__((__packed__)); After changes: struct roam_ctrl_cmd { union { u8 bssid[6]; /* 0 6 */ u8 roam_mode; /* 0 1 */ struct bss_bias_info_hdr bss; /* 0 1 */ struct low_rssi_scan_params params; /* 0 8 */ } info; /* 0 8 */ u8 roam_ctrl; /* 8 1 */ /* size: 9, cachelines: 1, members: 2 */ /* last cacheline: 9 bytes */ } __attribute__((__packed__)); With these changes fix the following warning: drivers/net/wireless/ath/ath6kl/wmi.h:1658:20: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Signed-off-by: Gustavo A. R. Silva --- Changes in v2: - Create new separate struct bss_bias_info_hdr, and use transparent struct members (in struct bss_bias_info) instead of rearranging members in struct roam_ctrl_cmd. - Update subject line - Add 'wifi:' prefix. v1: - Link: https://lore.kernel.org/linux-hardening/aR153k4ExCD-QTMq@kspp/ drivers/net/wireless/ath/ath6kl/wmi.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/ath6kl/wmi.h b/drivers/net/wireless/ath/ath6kl/wmi.h index 3080d82e25cc..d2a5c96fc878 100644 --- a/drivers/net/wireless/ath/ath6kl/wmi.h +++ b/drivers/net/wireless/ath/ath6kl/wmi.h @@ -1635,8 +1635,12 @@ struct bss_bias { s8 bias; } __packed; -struct bss_bias_info { +struct bss_bias_info_hdr { u8 num_bss; +} __packed; + +struct bss_bias_info { + struct bss_bias_info_hdr; struct bss_bias bss_bias[]; } __packed; @@ -1652,7 +1656,7 @@ struct roam_ctrl_cmd { union { u8 bssid[ETH_ALEN]; /* WMI_FORCE_ROAM */ u8 roam_mode; /* WMI_SET_ROAM_MODE */ - struct bss_bias_info bss; /* WMI_SET_HOST_BIAS */ + struct bss_bias_info_hdr bss; /* WMI_SET_HOST_BIAS */ struct low_rssi_scan_params params; /* WMI_SET_LRSSI_SCAN_PARAMS */ } __packed info; -- 2.43.0