From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793716672; b=FNdQ+tctytk7rymdttqLq2DJRIRvCsFPMk0IVU7kxgbH0w66SvXnIVxg9ih1Vd1Pt2uR Ki3LPJdutdtvPYmpJBemGj+v10N1n4yJJDzCVFB7YqeWeiMj97GMCWkttnQiJ813hX0J5 5Nd+ot0mgdrQCxU64sjuMCckZCREYkpFcQrWVRTYBdiS0LJVd/l2I0vAbm2gy9RwW3u7r BYIuGSBA4TJJt69GfzHJGf1CBcDrF8RgMF33QF0rB3b1mRWE1xQ3fQ+yEnrsbXVNxdUtv 88/y4dpPXjrQIhMZgUSbpbKHPZei3qdQqA/+SN3KabrA/1OcZr7961KVq5uPRDqLFLA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793716672; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=0II1/XloAzTRVHk+66VdnRMv+5KhxgQ23WNutsL+clc=; b=4JEhs7BUu27FdVR3T06QN9iiGodG9aFf3VmsQb/XPyo/elkfz1XHJry2D0gj9VIc7SHD 0JQv+BwwUwD5yJclqBS6NPJGnC9kSaQn25aM0LkPtpkPJJunUcr1bLmQuuP+664P28wqc kL5EmtFTcu+322kzEr54KO8pIEch03/gTj4SswO7xdYKVWBkBbyu2rHtlrg8og1fa9M3N OeFyL22uMRvz+btZivr14k5qPwfP7Zy4YauYpOKd1ycU//Itz6ue9Uxrf/1+coQGm+ITL 6CTX1DP+b1vjeTMTA/BllqJNNlhFV9FURUkynoLk+dsU2rviN2qzkSdU2EWRBNfNK1A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=i6Bz5XvT; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4A1CE606A327 for ; Tue, 3 Nov 2026 14:37:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=i6Bz5XvT Received: by smtp.kernel.org (Postfix) with ESMTPSA id B25101F000C1; Tue, 3 Nov 2026 14:37:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793716671; bh=0II1/XloAzTRVHk+66VdnRMv+5KhxgQ23WNutsL+clc=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=i6Bz5XvT3+jy3Oywmzx8YGv8qniQBhMuP+JYgECQEe1UWtUkJdV+sm5lxYCCDfCMp nMfnM1nV0KjaL5RD+OkrgHljPi/CFwpax/YarykAnK4cOWCy5RmwDaEGQUSk682vTi sFRic20cO7/tT3S5jeOrwdvQFGviWH9T+3LW5t7Tk2nwkcP9TfuPXMoA7BNqp9z7MD JJoovQ/ieqj1Fv8VASBdkmQqdpJwesGT35fOUFxz8vpc5zlxVimTn69mJ27ck/OU39 8AXpGKOmnXyMxZMnriOB4L5myK0d92VGnsaRk2srqhdvzy7QM6sV6+5i4eEHqDxQlr DGtbMI65KgiUw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH rdma-rc] RDMA/mlx5: Fix DevX umem page size truncation for pages >= 4G Reply-To: sashiko-reviews@lists.linux.dev To: 0z5a Cc: linux-rdma@vger.kernel.org In-Reply-To: <20261103142804.67210-1-dezhen.lu@student.uni-tuebingen.de> References: <20261103142804.67210-1-dezhen.lu@student.uni-tuebingen.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 03 Nov 2026 14:37:51 +0000 X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > From: Dezhen Lu >=20 > devx_umem_find_best_pgsize() computes the page size in an unsigned long > but returns it as unsigned int, and devx_umem_reg_cmd_alloc() stores it > in an unsigned int. When the DMA mapping of the umem is contiguous and > aligned to 4 GiB or more, and the umem length is a multiple of that > size, ib_umem_find_best_pgoff() selects a page size >=3D 2^32. Since the > value is a power of two, the truncation turns it into 0 and the > registration fails with -EINVAL. >=20 > The umem log_page_size field is 5 bits wide on top of > MLX5_ADAPTER_PAGE_SHIFT, so the command can encode these page sizes. >=20 > Seen on two GH200 nodes (ConnectX-7, firmware 32.38.3056 and > 32.43.1014) with a dma-buf exported from cudaMalloc memory: registering > [ ... ] > GH200 nodes described above. >=20 > Fixes: 7610ab57de56 ("RDMA/mlx5: Allow larger pages in DevX umem") > Cc: stable@vger.kernel.org > Signed-off-by: Dezhen Lu Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261103142804.6721= 0-1-dezhen.lu@student.uni-tuebingen.de?part=3D1