Merge tag 'for-linus-2019-11-08' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Two NVMe device removal crash fixes, and a compat fixup for for an
   ioctl that was introduced in this release (Anton, Charles, Max - via
   Keith)

 - Missing error path mutex unlock for drbd (Dan)

 - cgroup writeback fixup on dead memcg (Tejun)

 - blkcg online stats print fix (Tejun)

* tag 'for-linus-2019-11-08' of git://git.kernel.dk/linux-block:
  cgroup,writeback: don't switch wbs immediately on dead wbs if the memcg is dead
  block: drbd: remove a stray unlock in __drbd_send_protocol()
  blkcg: make blkcg_print_stat() print stats only for online blkgs
  nvme: change nvme_passthru_cmd64 to explicitly mark rsvd
  nvme-multipath: fix crash in nvme_mpath_clear_ctrl_paths
  nvme-rdma: fix a segmentation fault during module unload

6 files changed, 25 insertions, 9 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 5d21027b1faf..1eb8895be4c6 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -934,9 +934,14 @@ static int blkcg_print_stat(struct seq_file *sf, void *v)
                 int i;
                 bool has_stats = false;
 
+                spin_lock_irq(&blkg->q->queue_lock);
+
+                if (!blkg->online)
+                        goto skip;
+
                 dname = blkg_dev_name(blkg);
                 if (!dname)
-                        continue;
+                        goto skip;
 
                 /*
                  * Hooray string manipulation, count is the size written NOT
@@ -946,8 +951,6 @@ static int blkcg_print_stat(struct seq_file *sf, void *v)
                  */
                 off += scnprintf(buf+off, size-off, "%s ", dname);
 
-                spin_lock_irq(&blkg->q->queue_lock);
-
                 blkg_rwstat_recursive_sum(blkg, NULL,
                                 offsetof(struct blkcg_gq, stat_bytes), &rwstat);
                 rbytes = rwstat.cnt[BLKG_RWSTAT_READ];
@@ -960,8 +963,6 @@ static int blkcg_print_stat(struct seq_file *sf, void *v)
                 wios = rwstat.cnt[BLKG_RWSTAT_WRITE];
                 dios = rwstat.cnt[BLKG_RWSTAT_DISCARD];
 
-                spin_unlock_irq(&blkg->q->queue_lock);
-
                 if (rbytes || wbytes || rios || wios) {
                         has_stats = true;
                         off += scnprintf(buf+off, size-off,
@@ -999,6 +1000,8 @@ static int blkcg_print_stat(struct seq_file *sf, void *v)
                                 seq_commit(sf, -1);
                         }
                 }
+        skip:
+                spin_unlock_irq(&blkg->q->queue_lock);
         }
 
         rcu_read_unlock();
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 5b248763a672..a18155cdce41 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -786,7 +786,6 @@ int __drbd_send_protocol(struct drbd_connection *connection, enum drbd_packet cm
 
         if (nc->tentative && connection->agreed_pro_version < 92) {
                 rcu_read_unlock();
-                mutex_unlock(&sock->mutex);
                 drbd_err(connection, "--dry-run is not supported by peer");
                 return -EOPNOTSUPP;
         }
diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c
index fc99a40c1ec4..e0f064dcbd02 100644
--- a/drivers/nvme/host/multipath.c
+++ b/drivers/nvme/host/multipath.c
@@ -158,9 +158,11 @@ void nvme_mpath_clear_ctrl_paths(struct nvme_ctrl *ctrl)
         struct nvme_ns *ns;
 
         mutex_lock(&ctrl->scan_lock);
+        down_read(&ctrl->namespaces_rwsem);
         list_for_each_entry(ns, &ctrl->namespaces, list)
                 if (nvme_mpath_clear_current_path(ns))
                         kblockd_schedule_work(&ns->head->requeue_work);
+        up_read(&ctrl->namespaces_rwsem);
         mutex_unlock(&ctrl->scan_lock);
 }
 
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index f19a28b4e997..cb4c3000a57e 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -2133,8 +2133,16 @@ err_unreg_client:
 
 static void __exit nvme_rdma_cleanup_module(void)
 {
+        struct nvme_rdma_ctrl *ctrl;
+
         nvmf_unregister_transport(&nvme_rdma_transport);
         ib_unregister_client(&nvme_rdma_ib_client);
+
+        mutex_lock(&nvme_rdma_ctrl_mutex);
+        list_for_each_entry(ctrl, &nvme_rdma_ctrl_list, list)
+                nvme_delete_ctrl(&ctrl->ctrl);
+        mutex_unlock(&nvme_rdma_ctrl_mutex);
+        flush_workqueue(nvme_delete_wq);
 }
 
 module_init(nvme_rdma_init_module);
diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 8461a6322039..335607b8c5c0 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -576,10 +576,13 @@ void wbc_attach_and_unlock_inode(struct writeback_control *wbc,
         spin_unlock(&inode->i_lock);
 
         /*
-         * A dying wb indicates that the memcg-blkcg mapping has changed
-         * and a new wb is already serving the memcg.  Switch immediately.
+         * A dying wb indicates that either the blkcg associated with the
+         * memcg changed or the associated memcg is dying.  In the first
+         * case, a replacement wb should already be available and we should
+         * refresh the wb immediately.  In the second case, trying to
+         * refresh will keep failing.
          */
-        if (unlikely(wb_dying(wbc->wb)))
+        if (unlikely(wb_dying(wbc->wb) && !css_is_dying(wbc->wb->memcg_css)))
                 inode_switch_wbs(inode, wbc->wb_id);
 }
 EXPORT_SYMBOL_GPL(wbc_attach_and_unlock_inode);
diff --git a/include/uapi/linux/nvme_ioctl.h b/include/uapi/linux/nvme_ioctl.h
index e168dc59e9a0..d99b5a772698 100644
--- a/include/uapi/linux/nvme_ioctl.h
+++ b/include/uapi/linux/nvme_ioctl.h
@@ -63,6 +63,7 @@ struct nvme_passthru_cmd64 {
         __u32   cdw14;
         __u32   cdw15;
         __u32   timeout_ms;
+        __u32   rsvd2;
         __u64   result;
 };