From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 3F1132E6CA8 for ; Tue, 23 Dec 2025 04:42:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766464942; cv=none; b=TdFsEtBlw5UEdmkHBL/hoI80Px5HM2O9z0OJXDJkz7QRESj41/12FE1n5WNYDeTFfuTK8oVelqx0kVs0trswGT/0w6JKsmFxLaBteOSisM/LNO1n9mHm7SIWHHwURlfDuFnH/KkpXMTuJznNTFtk9R9oY74w9EIaMiQ5gLDJmmk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1766464942; c=relaxed/simple; bh=5OrutWyQ4GJ47KYUidPFQG7Tk44Gkgw9O+NSI2QmWuA=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=ZHJqeU6fL00HxbD/3A7rN0R6kJTzRbFpiJlJFGd5vqOWRirtS8iFlQToO3IAb+SruqE4yyXLVujrB7Jhfd2mfaMdRInTLazSlEJvuNHD20cQsYKR8UMOL54C3YUMpPig4dK3Bk3v+aX0YvQVQagxjilrN1CiIuDXO8HaoMNCYyw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=OhTKFi8t; arc=none smtp.client-ip=91.218.175.185 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="OhTKFi8t" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1766464938; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=nFthc9CHrZ5Y0LBu95uJirfebLtW2A/ghS+MKel5wj8=; b=OhTKFi8tKHW5AC0s7ePwfmTzQ7GBU7Kpipxr3b71lRofQ9Pe6uKUFMyaEBcwxU6amreNbq htvs1sOv7zj+233G2DHEbyytrMhUg/dwjkOowbJlfJEZn3hZuisH0iptiOzLqiybi3TyYC LRZDx1fzPSTpNyZe4HYBM5Kwq+Qreh8= From: Zhu Yanjun To: zyjzyj2000@gmail.com, jgg@ziepe.ca, leon@kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Gustavo A. R. Silva" , Zhu Yanjun Subject: [PATCH v3 1/1] RDMA/rxe: Avoid -Wflex-array-member-not-at-end warnings Date: Mon, 22 Dec 2025 23:41:29 -0500 Message-Id: <20251223044129.6232-1-yanjun.zhu@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: "Gustavo A. R. Silva" -Wflex-array-member-not-at-end was introduced in GCC-14, and we are getting ready to enable it, globally. Use the new TRAILING_OVERLAP() helper to fix the following warning: 21 drivers/infiniband/sw/rxe/rxe_verbs.h:271:33: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] This helper creates a union between a flexible-array member (FAM) and a set of MEMBERS that would otherwise follow it. This overlays the trailing MEMBER struct ib_sge sge[RXE_MAX_SGE]; onto the FAM struct rxe_recv_wqe::dma.sge, while keeping the FAM and the start of MEMBER aligned. The static_assert() ensures this alignment remains, and it's intentionally placed inmediately after the related structure --no blank line in between. Lastly, move the conflicting declaration struct rxe_resp_info resp; to the end of the corresponding structure. Reviewed-by: Zhu Yanjun Signed-off-by: Gustavo A. R. Silva --- V2->V3: Replace struct ib_sge with struct rxe_sge --- drivers/infiniband/sw/rxe/rxe_verbs.h | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h index fd48075810dd..3ffd7be8e7b1 100644 --- a/drivers/infiniband/sw/rxe/rxe_verbs.h +++ b/drivers/infiniband/sw/rxe/rxe_verbs.h @@ -219,12 +219,6 @@ struct rxe_resp_info { u32 rkey; u32 length; - /* SRQ only */ - struct { - struct rxe_recv_wqe wqe; - struct ib_sge sge[RXE_MAX_SGE]; - } srq_wqe; - /* Responder resources. It's a circular list where the oldest * resource is dropped first. */ @@ -232,7 +226,15 @@ struct rxe_resp_info { unsigned int res_head; unsigned int res_tail; struct resp_res *res; + + /* SRQ only */ + /* Must be last as it ends in a flexible-array member. */ + TRAILING_OVERLAP(struct rxe_recv_wqe, wqe, dma.sge, + struct rxe_sge sge[RXE_MAX_SGE]; + ) srq_wqe; }; +static_assert(offsetof(struct rxe_resp_info, srq_wqe.wqe.dma.sge) == + offsetof(struct rxe_resp_info, srq_wqe.sge)); struct rxe_qp { struct ib_qp ibqp; @@ -269,7 +271,6 @@ struct rxe_qp { struct rxe_req_info req; struct rxe_comp_info comp; - struct rxe_resp_info resp; atomic_t ssn; atomic_t skb_out; @@ -289,6 +290,9 @@ struct rxe_qp { spinlock_t state_lock; /* guard requester and completer */ struct execute_work cleanup_work; + + /* Must be last as it ends in a flexible-array member. */ + struct rxe_resp_info resp; }; enum { -- 2.39.5