From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=148.163.156.1 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792511423; b=Jf+8mBnNFlbxWhcjvbsZmB4Ywnty17UpR4ItQuQsaLlZaQG52Qxcy/4c/sr73RouztYh YOKTWpgaG/8WizhM2OWQaAl/sBRyFhSbiGzmhCfWnk6veQ4A0TETybonxhWZCLkw17vbA IsvwHQTC0xKVY5JUbuH8MCOHXeiXNmlbHHwmxqviDo1qa6uvq/02YUumUyC2wySWgSWij 9Y8bXY9/GFQhVNfYG6+9A588jvc89gYCb2znJdrcBJo+uAtIndU5zizGYTcyHsLtFZWWw vHlDkpQu6HtYxDiVHkOamOq00AI1B2rZMqVJPAOLhtIKzINwdvnyuMYnCd40rCYqq+A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792511423; h=DMARC-Filter:Received:DKIM-Signature:Received:Received:Received: Received:Received:Received:Received:From:To:Cc:Subject:In-Reply-To: References:Date:Message-ID:User-Agent:MIME-Version:Content-Type: X-TM-AS-GCONF:X-Proofpoint-GUID:X-Proofpoint-Spam-Info: X-Proofpoint-Spam-Details-Enc:X-Proofpoint-ORIG-GUID: X-Authority-Analysis:X-Proofpoint-Virus-Version: X-Proofpoint-Spam-Details; bh=AbcauNFsMvIFMj9DrGI69mbjEH96tjnPD90nswn6J9o=; b=Y2OCRrij+U6XgHN/UzXqkfy/rs5LO8Un8JB6o+tzWEYXvephDk+5DlHHEqQPnz84bP1P nY1rrDASPf46OABT5xtkW49xBdkYHBIU0l0MW5KefLb1koSCPg99SyVF4k5cLgpRGELYi WgO6pmvuyEbqw33hF7MPXHdULLYz8Eo0SaHHq+jTy8wofo4Ma4SjkosbtvjGiZCaVEW6M PQ2UlKJOlvk7AsIjmHzIFfqixgJoCtU2ecx9YD6BoaZRCD2rEjtUWbIASgZoqqw475LrA T/HL0sk12UVJh4SoQBbuqRwNhmLEtKsU3ajoPw2ZvK8mZq69dYF3kdsikNBQqZAvx6g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=Nj+bCtg5; arc=none smtp.remote-ip=148.163.156.1 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5FC82606A31F; Tue, 20 Oct 2026 15:50:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 5FC82606A31F Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=Nj+bCtg5 Received: from pps.filterd (m0360083.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 69KDE9cj2677984; Tue, 20 Oct 2026 15:49:51 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=pp1; bh=AbcauNFsMvIFMj9DrGI69mbjEH96tj nPD90nswn6J9o=; b=Nj+bCtg5LQtv5b9kOdBRgD+y+3jtCnNDgftuKCmsvm2Xp/ EuHIeEXU2rRwXtkuULpCgU9FpZNFO7ouYmZjOICoFdMrnCbbeLWzvS/jPy/woMTI nKK2wyrEz9+lDj2NSoL7Krh5BFidTZQ0UH84xYjM8NYOVILB9la/2i4870L4lUdz qviAbsOOoER0obe6/kUW4my16h/eX9p1xW0LLRjdLHuI4kR1oxn5SEbGht/3Z7lw Jd+NoFg3KcuTPrHW2vCqwIwtyjQZKHa5Qbq0l9J8d+P7u3kTxTmNvqvHuNgcDjBS vjMPerM5Qbf64EvXGVzF1latqnxT7UeMyTVYnbdA== Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4hdw58kscx-1 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 20 Oct 2026 15:49:51 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.11/8.18.1.11) with ESMTP id 69KDJv5W1543022; Tue, 20 Oct 2026 15:49:50 GMT Received: from smtprelay06.wdc07v.mail.ibm.com ([172.16.1.73]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 4he6gq92ha-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 20 Oct 2026 15:49:50 +0000 (GMT) Received: from smtpav02.dal12v.mail.ibm.com (smtpav02.dal12v.mail.ibm.com [10.241.53.101]) by smtprelay06.wdc07v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 69KFnnsS18875010 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 20 Oct 2026 15:49:49 GMT Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7BB8B5805C; Tue, 20 Oct 2026 15:49:49 +0000 (GMT) Received: from smtpav02.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5E6725805A; Tue, 20 Oct 2026 15:49:49 +0000 (GMT) Received: from e (unknown [9.61.26.156]) by smtpav02.dal12v.mail.ibm.com (Postfix) with ESMTPS; Tue, 20 Oct 2026 15:49:49 +0000 (GMT) From: Dave Marquardt To: sashiko-bot@kernel.org Cc: sashiko-reviews@lists.linux.dev, linux-scsi@vger.kernel.org Subject: Re: [PATCH v15 04/11] scsi: ibmvfc: add basic FPIN support In-Reply-To: (sashiko-bot@kernel.org's message of "Mon, 19 Oct 2026 22:35:19 +0000") References: <20261019-ibmvfc-fpin-support-v15-0-a858726e178a@linux.ibm.com> <20261019-ibmvfc-fpin-support-v15-4-a858726e178a@linux.ibm.com> Date: Tue, 20 Oct 2026 10:49:49 -0500 Message-ID: <87bj8ol6ci.fsf@linux.ibm.com> User-Agent: Gnus/5.13 (Gnus v5.13) X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-GUID: vjIIQMieu-JBcIXx0Xsi0NSqVLdqQGYp X-Proofpoint-Spam-Info: AW1haW4tMjYxMDIwMDA2MiBTYWx0ZWRfX6SpOG8KH04c9 3NQEXei1bNkFQNUSIPoyHiSNzAQWy1Sdpx24U4O/SaRPIW8VjJt36rHHZdfQFt2gv1mT8qiMBEG WL0iCBH5tSDXNPKsIHb3N2urFbwOw7I= X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYxMDIwMDA2MiBTYWx0ZWRfXxONzXhU3f/rY zf3xjQXjoY6+P/1tAJfVb+klS3f+vsly7yT6rfWttpWIoHuQ9JCfycrvAu6KIBXM52RPy5e4kcd +1WBRcNX+rgRwsryE2WuK6nUAGXUcFsrFT0s/ZfzZRInTX8HcMRJk+G4icIOQdpxBZclez/Lrvx lYtGzRFTlKAlsAEby77xMT7IGyzWpgmxFpIA+zlbV7F1eap1wzqcvOTlwsBPB1qcQ61tTt5E4it WX89knNM4dwxoZBNRfEnoCZntXZYYLzUNV6F1KaQREAhSZiy/deAkBL7y1mxUU2W+lvbNqsW5XY NP4sZKeEa2LSGn3A1LqesvbkUOCWS6yZ8k0nsxXsO9rqnLPluAigncUwlbZgDAKN4KWrlBnQdZG hv4jLR8ixKTOlolaTI+QBwIIgCZ698Cwq7mSSxP71iquunKxwysXjeJfxbL78FabWmqenqacUju l8MxkcJc4ML+los22TA== X-Proofpoint-ORIG-GUID: vjIIQMieu-JBcIXx0Xsi0NSqVLdqQGYp X-Authority-Analysis: v=2.4 cv=Ob4NnRTY c=1 sm=1 tr=0 ts=6ad78d9f cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=660iZSQnnn4A:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=iQ6ETzBq9ecOQQE5vZCe:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=v9ftGglcpUR1sx4fu-4A:9 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-10-20_02,2026-10-19_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 adultscore=0 phishscore=0 spamscore=0 suspectscore=0 lowpriorityscore=0 clxscore=1015 impostorscore=0 priorityscore=1501 malwarescore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2610190000 definitions=main-2610200062 sashiko-bot@kernel.org writes: > Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: > - [High] scsi: ibmvfc: wrong fpin_workq teardown order in ibmvfc_probe() error path > -- > > commit f3dce48358b69cb9e305579053b02a88579e0f88 > Author: Dave Marquardt > > scsi: ibmvfc: add basic FPIN support > > This commit adds basic Fabric Performance Impact Notification (FPIN) > support to the ibmvfc driver by offloading IBMVFC_AE_FPIN async events to > a per-adapter ordered workqueue, converting VIOS FPIN messages into > fc_els_fpin structures for fc_host_fpin_rcv(), and adding KUnit test > coverage. > >> diff --git a/drivers/scsi/ibmvscsi/ibmvfc-core.c b/drivers/scsi/ibmvscsi/ibmvfc-core.c >> index 0fe6b6f4260ba..0750e722c46c5 100644 >> --- a/drivers/scsi/ibmvscsi/ibmvfc-core.c >> +++ b/drivers/scsi/ibmvscsi/ibmvfc-core.c > > [ ... ] > >> @@ -6898,9 +7169,15 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id) >> INIT_WORK(&vhost->rport_add_work_q, ibmvfc_rport_add_thread); >> mutex_init(&vhost->passthru_mutex); >> >> - if ((rc = ibmvfc_alloc_mem(vhost))) >> + vhost->fpin_workq = alloc_ordered_workqueue("%s-fpin-workq-%u", 0, >> + IBMVFC_NAME, shost->host_no); >> + if (!vhost->fpin_workq) >> goto free_scsi_host; >> >> + rc = ibmvfc_alloc_mem(vhost); >> + if (rc) >> + goto free_workq; >> + >> vhost->work_thread = kthread_run(ibmvfc_work, vhost, "%s_%d", IBMVFC_NAME, >> shost->host_no); >> >> @@ -6946,6 +7223,8 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id) >> kthread_stop(vhost->work_thread); >> free_host_mem: >> ibmvfc_free_mem(vhost); >> +free_workq: >> + destroy_workqueue(vhost->fpin_workq); >> free_scsi_host: >> scsi_host_put(shost); >> out: > > [Severity: High] > Can the error unwind order in ibmvfc_probe() cause a use-after-free of > vhost->tgt_pool? > > In ibmvfc_remove(), destroy_workqueue(vhost->fpin_workq) is called after > ibmvfc_release_crq_queue(vhost) and before ibmvfc_free_mem(vhost): > > ibmvfc_release_crq_queue(vhost); > destroy_workqueue(vhost->fpin_workq); > > ibmvfc_free_mem(vhost); > > As described in the commit message, this ordering ensures that queued FPIN > work items are drained before ibmvfc_free_mem() destroys vhost->tgt_pool. > > In ibmvfc_probe(), however, vhost->fpin_workq is allocated before > ibmvfc_alloc_mem(vhost), so the error unwind path runs ibmvfc_free_mem() > before destroy_workqueue(vhost->fpin_workq): > > release_crq: > ibmvfc_release_crq_queue(vhost); > kill_kthread: > kthread_stop(vhost->work_thread); > free_host_mem: > ibmvfc_free_mem(vhost); > free_workq: > destroy_workqueue(vhost->fpin_workq); > > Because vhost->work_thread is started and ibmvfc_init_crq() registers the > CRQ and enables interrupts before scsi_add_host() and > ibmvfc_create_trace_file() are called, a partner-initiated CRQ handshake > and subsequent IBMVFC_AE_FPIN event can queue ibmvfc_process_async_work() > on vhost->fpin_workq before scsi_add_host() or ibmvfc_create_trace_file() > fails. > > If that happens, ibmvfc_free_mem() will call > mempool_destroy(vhost->tgt_pool) while ibmvfc_process_async_work() is > still running or pending, and ibmvfc_process_async_work() -> > kref_put(&tgt->kref, ibmvfc_release_tgt) -> > mempool_free(tgt, tgt->vhost->tgt_pool) will access the destroyed > tgt_pool. > > Should vhost->fpin_workq be allocated after ibmvfc_alloc_mem(vhost) (or > destroyed before ibmvfc_free_mem(vhost) on the error path) to match the > teardown order in ibmvfc_remove()? Yes. I'll change the teardown order to match the teardown order in ibmvfc_remove(). -Dave