4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Martin Brandenburg <martin@xxxxxxxxxxxx> commit 1ec1688c5360e14dde4094d6acbf7516bf6db37e upstream. 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: [<ffffffff8124171f>] 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 <martin@xxxxxxxxxxxx> Acked-by: Mike Marshall <hubcap@xxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/orangefs/devorangefs-req.c | 9 +++++++-- fs/orangefs/orangefs-kernel.h | 1 + fs/orangefs/super.c | 23 ++++++++++++++++------- 3 files changed, 24 insertions(+), 9 deletions(-) --- a/fs/orangefs/devorangefs-req.c +++ b/fs/orangefs/devorangefs-req.c @@ -208,14 +208,19 @@ restart: 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)); --- 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; }; --- a/fs/orangefs/super.c +++ b/fs/orangefs/super.c @@ -493,7 +493,7 @@ struct dentry *orangefs_mount(struct fil if (ret) { d = ERR_PTR(ret); - goto free_op; + goto free_sb_and_op; } /* @@ -519,6 +519,9 @@ struct dentry *orangefs_mount(struct fil 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 fil 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 */ 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