Re: WARNING: lock held when returning to user space in grab_super

2019-01-02 Thread Tejun Heo
On Thu, Jan 03, 2019 at 01:49:55AM +0900, Tetsuo Handa wrote: > kernfs_node_dentry() calls lookup_one_len_unlocked() which involves > memory allocation, and memory allocation fault injection made > lookup_one_len_unlocked() fail, and thus kernfs_node_dentry() failed. > What's strange? So,

Re: WARNING: lock held when returning to user space in grab_super

2019-01-02 Thread Tetsuo Handa
On 2019/01/03 1:16, Tejun Heo wrote: > Happy new year, Tetsuo. > > On Wed, Jan 02, 2019 at 09:08:56PM +0900, Tetsuo Handa wrote: >> According to commit 633feee310de6b6c ("cgroup: refactor mount path and >> clearly distinguish v1 and v2 paths"), cgroup_do_mount() is failing to >> do full teardown

Re: WARNING: lock held when returning to user space in grab_super

2019-01-02 Thread Tejun Heo
Happy new year, Tetsuo. On Wed, Jan 02, 2019 at 09:08:56PM +0900, Tetsuo Handa wrote: > According to commit 633feee310de6b6c ("cgroup: refactor mount path and > clearly distinguish v1 and v2 paths"), cgroup_do_mount() is failing to > do full teardown steps for kernfs_mount()

Re: WARNING: lock held when returning to user space in grab_super

2019-01-02 Thread Tetsuo Handa
Hello, Tejun. [ 1100.561812] FAULT_INJECTION: forcing a failure. [ 1100.561812] name failslab, interval 1, probability 0, space 0, times 0 [ 1100.625231] CPU: 1 PID: 29677 Comm: syz-executor0 Not tainted 4.20.0+ #396 [ 1100.632289] Hardware name: Google Google Compute Engine/Google Compute

WARNING: lock held when returning to user space in grab_super

2019-01-02 Thread syzbot
Hello, syzbot found the following crash on: HEAD commit:195303136f19 Merge tag 'kconfig-v4.21-2' of git://git.kern.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=118961fd40 kernel config: https://syzkaller.appspot.com/x/.config?x=5e7dc790609552d7