Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754264AbdDNSXL (ORCPT ); Fri, 14 Apr 2017 14:23:11 -0400 Received: from mail-yb0-f175.google.com ([209.85.213.175]:32897 "EHLO mail-yb0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752862AbdDNSXJ (ORCPT ); Fri, 14 Apr 2017 14:23:09 -0400 From: Martin Brandenburg To: torvalds@linux-foundation.org, hubcap@omnibond.com, viro@zeniv.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Martin Brandenburg , stable@vger.kernel.org Subject: [PATCH] orangefs: free superblock when mount fails Date: Fri, 14 Apr 2017 14:22:41 -0400 Message-Id: <20170414182241.14659-1-martin@omnibond.com> X-Mailer: git-send-email 2.11.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4060 Lines: 116 Otherwise lockdep says: [ 1337.483798] ================================================ [ 1337.483999] [ BUG: lock held when returning to user space! ] [ 1337.484252] 4.11.0-rc6 #19 Not tainted [ 1337.484423] ------------------------------------------------ [ 1337.484626] mount/14766 is leaving the kernel with locks still held! [ 1337.484841] 1 lock held by mount/14766: [ 1337.485017] #0: (&type->s_umount_key#33/1){+.+.+.}, at: [] sget_userns+0x2af/0x520 Caught by xfstests generic/413 which tried to mount with the unsupported mount option dax. Then xfstests generic/422 ran sync which deadlocks. Signed-off-by: Martin Brandenburg Cc: stable@vger.kernel.org --- fs/orangefs/devorangefs-req.c | 9 +++++++-- fs/orangefs/orangefs-kernel.h | 1 + fs/orangefs/super.c | 23 ++++++++++++++++------- 3 files changed, 24 insertions(+), 9 deletions(-) diff --git a/fs/orangefs/devorangefs-req.c b/fs/orangefs/devorangefs-req.c index c4ab6fdf17a0..e1534c9bab16 100644 --- a/fs/orangefs/devorangefs-req.c +++ b/fs/orangefs/devorangefs-req.c @@ -208,14 +208,19 @@ static ssize_t orangefs_devreq_read(struct file *file, continue; /* * Skip ops whose filesystem we don't know about unless - * it is being mounted. + * it is being mounted or unmounted. It is possible for + * a filesystem we don't know about to be unmounted if + * it fails to mount in the kernel after userspace has + * been sent the mount request. */ /* XXX: is there a better way to detect this? */ } else if (ret == -1 && !(op->upcall.type == ORANGEFS_VFS_OP_FS_MOUNT || op->upcall.type == - ORANGEFS_VFS_OP_GETATTR)) { + ORANGEFS_VFS_OP_GETATTR || + op->upcall.type == + ORANGEFS_VFS_OP_FS_UMOUNT)) { gossip_debug(GOSSIP_DEV_DEBUG, "orangefs: skipping op tag %llu %s\n", llu(op->tag), get_opname_string(op)); diff --git a/fs/orangefs/orangefs-kernel.h b/fs/orangefs/orangefs-kernel.h index 5e48a0be9761..8afac46fcc87 100644 --- a/fs/orangefs/orangefs-kernel.h +++ b/fs/orangefs/orangefs-kernel.h @@ -249,6 +249,7 @@ struct orangefs_sb_info_s { char devname[ORANGEFS_MAX_SERVER_ADDR_LEN]; struct super_block *sb; int mount_pending; + int no_list; struct list_head list; }; diff --git a/fs/orangefs/super.c b/fs/orangefs/super.c index cd261c8de53a..629d8c917fa6 100644 --- a/fs/orangefs/super.c +++ b/fs/orangefs/super.c @@ -493,7 +493,7 @@ struct dentry *orangefs_mount(struct file_system_type *fst, if (ret) { d = ERR_PTR(ret); - goto free_op; + goto free_sb_and_op; } /* @@ -519,6 +519,9 @@ struct dentry *orangefs_mount(struct file_system_type *fst, spin_unlock(&orangefs_superblocks_lock); op_release(new_op); + /* Must be removed from the list now. */ + ORANGEFS_SB(sb)->no_list = 0; + if (orangefs_userspace_version >= 20906) { new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES); if (!new_op) @@ -533,6 +536,10 @@ struct dentry *orangefs_mount(struct file_system_type *fst, return dget(sb->s_root); +free_sb_and_op: + /* Will call orangefs_kill_sb with sb not in list. */ + ORANGEFS_SB(sb)->no_list = 1; + deactivate_locked_super(sb); free_op: gossip_err("orangefs_mount: mount request failed with %d\n", ret); if (ret == -EINVAL) { @@ -558,12 +565,14 @@ void orangefs_kill_sb(struct super_block *sb) */ orangefs_unmount_sb(sb); - /* remove the sb from our list of orangefs specific sb's */ - - spin_lock(&orangefs_superblocks_lock); - __list_del_entry(&ORANGEFS_SB(sb)->list); /* not list_del_init */ - ORANGEFS_SB(sb)->list.prev = NULL; - spin_unlock(&orangefs_superblocks_lock); + if (!ORANGEFS_SB(sb)->no_list) { + /* remove the sb from our list of orangefs specific sb's */ + spin_lock(&orangefs_superblocks_lock); + /* not list_del_init */ + __list_del_entry(&ORANGEFS_SB(sb)->list); + ORANGEFS_SB(sb)->list.prev = NULL; + spin_unlock(&orangefs_superblocks_lock); + } /* * make sure that ORANGEFS_DEV_REMOUNT_ALL loop that might've seen us -- 2.11.0