From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4865C07542 for ; Sat, 25 May 2019 23:16:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 901CF2075E for ; Sat, 25 May 2019 23:16:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727456AbfEYXQi (ORCPT ); Sat, 25 May 2019 19:16:38 -0400 Received: from mga03.intel.com ([134.134.136.65]:31911 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727455AbfEYXQh (ORCPT ); Sat, 25 May 2019 19:16:37 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 May 2019 16:16:36 -0700 X-ExtLoop1: 1 Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.16]) by fmsmga005.fm.intel.com with ESMTP; 25 May 2019 16:16:36 -0700 Subject: [for-4.9.y PATCH] libnvdimm/namespace: Fix label tracking error From: Dan Williams To: stable@vger.kernel.org Cc: Jane Chu , Jeff Moyer , Erwin Tsaur , Johannes Thumshirn , linux-nvdimm@lists.01.org Date: Sat, 25 May 2019 16:02:49 -0700 Message-ID: <155882536896.2470998.15501697202623097741.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-2-gc94f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org commit c4703ce11c23423d4b46e3d59aef7979814fd608 upstream. Users have reported intermittent occurrences of DIMM initialization failures due to duplicate allocations of address capacity detected in the labels, or errors of the form below, both have the same root cause. nd namespace1.4: failed to track label: 0 WARNING: CPU: 17 PID: 1381 at drivers/nvdimm/label.c:863 RIP: 0010:__pmem_label_update+0x56c/0x590 [libnvdimm] Call Trace: ? nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm] nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm] uuid_store+0x17e/0x190 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x57/0xd0 do_syscall_64+0x60/0x210 Unfortunately those reports were typically with a busy parallel namespace creation / destruction loop making it difficult to see the components of the bug. However, Jane provided a simple reproducer using the work-in-progress sub-section implementation. When ndctl is reconfiguring a namespace it may take an existing defunct / disabled namespace and reconfigure it with a new uuid and other parameters. Critically namespace_update_uuid() takes existing address resources and renames them for the new namespace to use / reconfigure as it sees fit. The bug is that this rename only happens in the resource tracking tree. Existing labels with the old uuid are not reaped leading to a scenario where multiple active labels reference the same span of address range. Teach namespace_update_uuid() to flag any references to the old uuid for reaping at the next label update attempt. Cc: Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Link: https://github.com/pmem/ndctl/issues/91 Reported-by: Jane Chu Reported-by: Jeff Moyer Reported-by: Erwin Tsaur Cc: Johannes Thumshirn Signed-off-by: Dan Williams --- drivers/nvdimm/label.c | 29 ++++++++++++++++------------- drivers/nvdimm/namespace_devs.c | 15 +++++++++++++++ drivers/nvdimm/nd.h | 4 ++++ 3 files changed, 35 insertions(+), 13 deletions(-) diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c index 66a089d561cf..9108004a0d9b 100644 --- a/drivers/nvdimm/label.c +++ b/drivers/nvdimm/label.c @@ -490,15 +490,26 @@ static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd, - (unsigned long) to_namespace_index(ndd, 0); } +static void reap_victim(struct nd_mapping *nd_mapping, + struct nd_label_ent *victim) +{ + struct nvdimm_drvdata *ndd = to_ndd(nd_mapping); + u32 slot = to_slot(ndd, victim->label); + + dev_dbg(ndd->dev, "free: %d\n", slot); + nd_label_free_slot(ndd, slot); + victim->label = NULL; +} + static int __pmem_label_update(struct nd_region *nd_region, struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm, int pos, unsigned long flags) { u64 cookie = nd_region_interleave_set_cookie(nd_region); struct nvdimm_drvdata *ndd = to_ndd(nd_mapping); - struct nd_label_ent *label_ent, *victim = NULL; struct nd_namespace_label *nd_label; struct nd_namespace_index *nsindex; + struct nd_label_ent *label_ent; struct nd_label_id label_id; struct resource *res; unsigned long *free; @@ -551,18 +562,10 @@ static int __pmem_label_update(struct nd_region *nd_region, list_for_each_entry(label_ent, &nd_mapping->labels, list) { if (!label_ent->label) continue; - if (memcmp(nspm->uuid, label_ent->label->uuid, - NSLABEL_UUID_LEN) != 0) - continue; - victim = label_ent; - list_move_tail(&victim->list, &nd_mapping->labels); - break; - } - if (victim) { - dev_dbg(ndd->dev, "%s: free: %d\n", __func__, slot); - slot = to_slot(ndd, victim->label); - nd_label_free_slot(ndd, slot); - victim->label = NULL; + if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags) + || memcmp(nspm->uuid, label_ent->label->uuid, + NSLABEL_UUID_LEN) == 0) + reap_victim(nd_mapping, label_ent); } /* update index */ diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c index cf4a90b50f8b..e83453e1b308 100644 --- a/drivers/nvdimm/namespace_devs.c +++ b/drivers/nvdimm/namespace_devs.c @@ -1210,12 +1210,27 @@ static int namespace_update_uuid(struct nd_region *nd_region, for (i = 0; i < nd_region->ndr_mappings; i++) { struct nd_mapping *nd_mapping = &nd_region->mapping[i]; struct nvdimm_drvdata *ndd = to_ndd(nd_mapping); + struct nd_label_ent *label_ent; struct resource *res; for_each_dpa_resource(ndd, res) if (strcmp(res->name, old_label_id.id) == 0) sprintf((void *) res->name, "%s", new_label_id.id); + + mutex_lock(&nd_mapping->lock); + list_for_each_entry(label_ent, &nd_mapping->labels, list) { + struct nd_namespace_label *nd_label = label_ent->label; + struct nd_label_id label_id; + + if (!nd_label) + continue; + nd_label_gen_id(&label_id, nd_label->uuid, + __le32_to_cpu(nd_label->flags)); + if (strcmp(old_label_id.id, label_id.id) == 0) + set_bit(ND_LABEL_REAP, &label_ent->flags); + } + mutex_unlock(&nd_mapping->lock); } kfree(*old_uuid); out: diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index d869236b474f..bd29e598bac1 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -113,8 +113,12 @@ struct nd_percpu_lane { spinlock_t lock; }; +enum nd_label_flags { + ND_LABEL_REAP, +}; struct nd_label_ent { struct list_head list; + unsigned long flags; struct nd_namespace_label *label; };