From nobody Mon Sep 28 06:38:16 2026 Received: from mx0b-00364e01.pphosted.com (mx0b-00364e01.pphosted.com [148.163.139.74]) (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 B66E7488DAD for ; Tue, 25 Aug 2026 15:41:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.139.74 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787672513; cv=none; b=djCRgaR5MVjop8UCyzjS93PMom3LSREj9qAPFs1en14cndUz1sCxN8ZPCcUvTNSZBUdUr+p7ygPvZvYYoGq0ImD9q5INvvxsZDFddUdetAFDTOu/K7ep68vSFNWE19tHT/r4CrqD8rpzBoY+LxOBzsW0fqvne40Bzd3ZgmRw11c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787672513; c=relaxed/simple; bh=4U6b4lMIo9YhLUUS4w31/FBKnGIHgEqeIFYMnxkJ3x4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=kXyHw9f3Ja6uylP49zN+/Cxt+6b2OAbpXtYolsxuQi69xqNd+U6VL1XCQBF3DgwvryIHv838aONdo7Iq6HSUZGNryHIMt0SrYrv/dmlmvPZHUE3tdcKCXQHxk/5qiqXjnToPpkFoQiDZE0ODy8ldrcx9dFaPQT9qeJvNYqIIkRI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=columbia.edu; spf=pass smtp.mailfrom=columbia.edu; dkim=pass (2048-bit key) header.d=columbia.edu header.i=@columbia.edu header.b=E/vpUPHM; dkim=pass (2048-bit key) header.d=columbia.edu header.i=@columbia.edu header.b=TtRvxFpx; arc=none smtp.client-ip=148.163.139.74 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=columbia.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=columbia.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=columbia.edu header.i=@columbia.edu header.b="E/vpUPHM"; dkim=pass (2048-bit key) header.d=columbia.edu header.i=@columbia.edu header.b="TtRvxFpx" Received: from pps.filterd (m0167076.ppops.net [127.0.0.1]) by mx0b-00364e01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 67PFSi5W1798048 for ; Tue, 25 Aug 2026 11:41:49 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=columbia.edu; h= cc:content-transfer-encoding:content-type:date:from:message-id :mime-version:subject:to; s=pps01; bh=QwLCRXh5uHyDOTTjOuOoMoQZ5E jBHO2U2Wq2PbXccnM=; b=E/vpUPHMGDX4mzoaM1ksetBjwuidUdTfmE3t1/RoT0 MM5VKa2cOXBsOejTwhESCjxJk5tOZRY8VuIpkApfAuNB0tr8uXiXzHZavjaYZLJ3 HxeNkk9ggJttaVYJp4kpAZ+6Xjtals8Hmgzu94NbT9e6wd7XgUB/Dg/dpGIwJ7Oe xv9HJczLcyIzbZNReM/n0JY+w2P0PhYQqfwPzuWuJIOyeVTdXucl78xva10/RANN FXK5b0DiFijYYfUHPyMSaOXBhAdt1fImtKfIcL7Z3e3z6WkmD8s7l3h5fg9uO7ah cBesYgosn3JEZ2NGQNvS2vkSrz/BKDQLuCYBvRS+IUTg== Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by mx0b-00364e01.pphosted.com (PPS) with ESMTPS id 4g9d6t8dts-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Tue, 25 Aug 2026 11:41:49 -0400 (EDT) Received: by mail-qt1-f199.google.com with SMTP id d75a77b69052e-5283df62d68so65998191cf.0 for ; Tue, 25 Aug 2026 08:41:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=columbia.edu; s=lionmail; t=1787672508; x=1788277308; darn=vger.kernel.org; h=cc:to:message-id:content-transfer-encoding:content-type :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to:content-type; bh=QwLCRXh5uHyDOTTjOuOoMoQZ5EjBHO2U2Wq2PbXccnM=; b=TtRvxFpxs0EPUKYoYgrORrXoDuCooDEtmPRyL3YiC+nn5rUVGwn0ol0xwSPo0DL4V6 aGvA+b+tpN5c4AzssDKMcLHMF4MXVzPSWDfLyIvywSl2/Xt23wZlsaX5RUoIZhFjpXOM LCvidm7kwv1GSoKlUxa/xQCPruQXmiO4Oo++mkh4hlzaUlbLpw/0zuP3DkTKJEwcx90X qXUD1qOHn3bgotX/XCFyoIfdLAIoZw3i2XH9gava7ZTNBU76bUIYKJ4AaoZ1U23vVLW+ tIHU2jNdJpSL5pkvYlOX1q0J9eYjfYS8iXbYnMD1ekCsIA278ijU1zRnh+xKYQUIJ/H0 ROcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1787672508; x=1788277308; h=cc:to:message-id:content-transfer-encoding:content-type :mime-version:subject:date:from:x-gm-gg:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to:content-type; bh=QwLCRXh5uHyDOTTjOuOoMoQZ5EjBHO2U2Wq2PbXccnM=; b=KACe31Cllfs3Ga41FKRzbioE4CXShyuv6S+dfnKK4+d8ugUMNbO8db9i4/xvlVaDgv d701PAFqLaHq1IbEjQHpsrqjhtt78ynxrip5KCupNSspxkmqVANMry6SAsVd1PZhLKxN oD5gKPiwHacqPncposdekkXvu0uACO+7Af8AVEIPNNFko+D4ME40Bu4hJTmkXNh4Lure CdngjfMB3CqgxznppyJ+ep/djAhBu4ptoqFHTQ/q07zGJ2ExAK4F00j2b0RhJ+P37ZUl 5NmJmAZvrXkfQ1SpVCnqn7b/LszR2JhHjgTBxdiJDVxoBjcLDENWWfLbn9YHx1kdnpUF hcCQ== X-Forwarded-Encrypted: i=1; AHgh+Ro+K/jkQuEiJKA6eRxDLFynFk4xiwiPmAN3MfbUmi+g5Fg+h/U1c8OWB3YDboJBTppKQ5AlePiLz/yIK3s=@vger.kernel.org X-Gm-Message-State: AFuF++lSTLd2U3yMZ0WRoABKyTwP5Z6++RjY4XrMR7J/dLb4clJUty4b JYe8EQE6FGqRG9756H3FauAhbbWbcQoG7itVpkb2dwWDqHHArqKg44jCKE9MoL3pE1GQbSePELr ZqoGiX048RCrSOF8LFpVLWQPfUwSxbm+lK+QBJaG8BJcUDifIPSdpIK4Ixfw3Mw== X-Gm-Gg: AR+sD10eDyEK/IHdvpShGAr3/JJg/8p/gQ0D1KZcgYsW4FfYUduMEa9lFm05Y5Vs9Rg tH76FpCzm9SRWaZGq9hs+iF84DoSZny1CceOG7OXytBaj4RZR3BT3GYr80guHMQsgQg53A/aQKE gADYytlDOvMYc3PbkZBjku0WK4oEkxiStdunAzDxsFQfQ09jCxz4qcNESCAInGOiINLcwEUtatr /5biEz1iwxS1/i5lwWYbiK345JXP51Qmh6FHH9zU7kWuUMSERO5q5SP+gWb4sfQ8IkNG8qWPMNK e5bglWRF4sUkCq2baBye6zytRRYe28WwC4Z2/lfNq5ExxgSGkEDNZwvq4nhfq0ET0VfHRKeBFY9 gqdJMVcGroA== X-Received: by 2002:a05:622a:2304:b0:52d:825f:e53b with SMTP id d75a77b69052e-52df5be1347mr364493791cf.39.1787672508652; Tue, 25 Aug 2026 08:41:48 -0700 (PDT) X-Received: by 2002:a05:622a:2304:b0:52d:825f:e53b with SMTP id d75a77b69052e-52df5be1347mr364492811cf.39.1787672507964; Tue, 25 Aug 2026 08:41:47 -0700 (PDT) Received: from [127.0.1.1] ([37.142.157.200]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c250a5d62f7sm13523166b.2.2026.08.25.08.41.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Aug 2026 08:41:46 -0700 (PDT) From: Tal Zussman Date: Tue, 25 Aug 2026 11:41:38 -0400 Subject: [PATCH v2] libceph: remove pinning assertion in ceph_msg_data_iter_next() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260825-ceph-msgr-writeback-v2-1-840ef541b0c2@columbia.edu> X-B4-Tracking: v=1; b=H4sIALG3jWoC/22Nyw6CMBBFf4XM2pq2vKor/8OwaMsAo0JJC6gh/ LuALl2e5N5zZgjoCQOcoxk8ThTIdSvIQwS20V2NjMqVQXKZccUVs9g3rA21Z09PAxpt70xneSl TlKoSCOuz91jRa7deiy+H0dzQDptqWzQUBuffe3YS2+5XEPnfwiSYYLGq4jxNeJyY08W6x9ga0 kcsRyiWZfkAzVQMR8sAAAA= X-Change-ID: 20260808-ceph-msgr-writeback-a67d25e28f1e To: Ilya Dryomov , Alex Markuze , Viacheslav Dubeyko Cc: David Howells , "Matthew Wilcox (Oracle)" , Christoph Hellwig , ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org, Tal Zussman X-Mailer: b4 0.14.3-dev-d7477 X-Developer-Signature: v=1; a=ed25519-sha256; t=1787672505; l=1910; i=tz2294@columbia.edu; s=20250528; h=from:subject:message-id; bh=4U6b4lMIo9YhLUUS4w31/FBKnGIHgEqeIFYMnxkJ3x4=; b=J8rUOJi+qDcSqLzDz1UgDBe9qfIvhiQLPgUoj7vXWevZemD4rWIc6A7rKsIcnDnZGatFdbGzs r8cg6xe6BDsDj1kJmzGQyRmtEd+h9esjcsSJYLW8D1wGxP6vjvEkUkc X-Developer-Key: i=tz2294@columbia.edu; a=ed25519; pk=BIj5KdACscEOyAC0oIkeZqLB3L94fzBnDccEooxeM5Y= X-Proofpoint-GUID: Ltnc7Y3XWE7BIWc-ODQiZr-qflbeUEZY X-Proofpoint-ORIG-GUID: Ltnc7Y3XWE7BIWc-ODQiZr-qflbeUEZY X-Authority-Analysis: v=2.4 cv=T528ifKQ c=1 sm=1 tr=0 ts=6a8db7bd cx=c_pps a=WeENfcodrlLV9YRTxbY/uA==:117 a=VsYqNs1x6zyujO4rtox2PQ==:17 a=IkcTkHD0fZMA:10 a=Sv0fKeRqtYgA:10 a=x7bEGLp0ZPQA:10 a=A0y_DWxS2BwA:10 a=VkNPw1HP01LnGYTKEx00:22 a=Da8U98TiO7q1upZEImrf:22 a=Qm0qsxP7aFY2tkT6R2MF:22 a=VwQbUJbxAAAA:8 a=oCklooxHT9tjbPDfpeQA:9 a=QEXdDO2ut3YA:10 a=kacYvNCVWA4VmyqE58fU:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODI1MDEzMyBTYWx0ZWRfXye9xhqBWBPuk Z/HKGUo6f+Gg2GBt+D8yvHMdggHdUKx/kU4d5txq+873ADOd7tbweq4YvLJWATBmyLpIMjYHYHQ jHEypzeLqrgsg1PoOGZLhvlXJpdDHbdIEa7cEnv2F/KB7a6uuXVh4GkIPElmWOy8bzpNZhZqJ0M rcwY8gqnZjq/G0YYyglhG1T79q3427feZfJdRInhSX3afapaEdk9DaoBc2nu3WfiAX8rYGm9RRH a7lE0132+V/3LEAHunEU+OxQ+xnyCYKs2+BjuzmJb9XE1Pxy98LCjIM5xU2IX6sy7QTBxN7h9dK FwbqaV1jtgJpwDZKdaHzpcbxeTZCssHHVh/n/Xv0XEHu/XnKgjeSL82AwVcUuWuFP08VOrLXIEq k6KCrY0EoOQ5KiuitNpomojMgBsmnMizllMLWXhfb4cHMXp0hqSEiwS8QMnclVJmZhuDViiuKdj MDNJve77SWpM5ADsdDg== X-Proofpoint-Spam-Info: AW1haW4tMjYwODI1MDEzMyBTYWx0ZWRfXxed+I+NAP2Ug K+DEOv4Fscv5CbiXmukK4gtk4CwF45m0EZo4dtcrOukpQMCryhIMlDcQe3myNGxRYfhg4clgwlr x2QVZP7DnVdd743cGozEkPx6/odzFd+oH+G4mlMWBL7SFKp2tFHu X-Proofpoint-Virus-Version: vendor=nai engine=6900 definitions=11886 signatures=596817 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 spamscore=0 suspectscore=0 impostorscore=10 priorityscore=1501 lowpriorityscore=10 phishscore=0 malwarescore=0 adultscore=0 bulkscore=10 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608250133 ceph_msg_data_iter_next() gets a page reference from iov_iter_get_pages2() only to immediately drop it, asserting that the page is pinned some other way. The assertion is the last caller of PageWriteback() in the tree, blocking removal of the PG_writeback page flag accessors. Remove the assertion, as it is a CONFIG_DEBUG_VM-only check of an assumption the FIXME comment already documents. Converting to iov_iter_extract_pages() instead was considered, but the messenger never releases what it extracts, so it would still rely entirely on the caller holding the pages. That would be just as much of an abuse of the API, so leave it as-is for now. Signed-off-by: Tal Zussman Reviewed-by: Christoph Hellwig --- The assertion is the last caller of PageWriteback() in the tree. The removal of the PG_writeback page flag accessors will be sent separately. Changes in v2: - Only delete the assertion and leave the rest as-is, per Christoph. - Rebase onto latest ceph for-linus branch, as v1 was applied to the testing branch. - Link to v1: https://lore.kernel.org/r/20260817-ceph-msgr-writeback-v1-1-3= 8f3754034b9@columbia.edu --- net/ceph/messenger.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c index 34b3097b4c7b..95929eeb1f85 100644 --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -1003,7 +1003,6 @@ static struct page *ceph_msg_data_iter_next(struct ce= ph_msg_data_cursor *cursor, * we'll get an iov_iter_get_pages2 variant that doesn't take * page refs. Until then, just put the page ref. */ - VM_BUG_ON_PAGE(!PageWriteback(page) && page_count(page) < 2, page); put_page(page); =20 *length =3D min_t(size_t, len, cursor->resid); --- base-commit: 91880e4a7fac45bc407771bc57bbaf4f37e9b4c3 change-id: 20260808-ceph-msgr-writeback-a67d25e28f1e Best regards, --=20 Tal Zussman