On 01/17, Daniel Hokka Zakrisson wrote: > > >> Call Trace: > >> [<c03be6f0>] _spin_lock_irqsave+0x20/0x90 > >> [<c01f6115>] lockd_down+0x125/0x190 > >> [<c01d26bd>] nfs_free_server+0x6d/0xd0 > >> [<c01d8e9c>] nfs_kill_super+0xc/0x20 > >> [<c0161c5d>] deactivate_super+0x7d/0xa0 > >> [<c0175e0e>] release_mounts+0x6e/0x80 > >> [<c0175e86>] __put_mnt_ns+0x66/0x80 > >> [<c0132b3e>] free_nsproxy+0x5e/0x60 > >> [<c011f021>] do_exit+0x791/0x810 > >> [<c011f0c6>] do_group_exit+0x26/0x70 > >> [<c0103142>] sysenter_past_esp+0x5f/0x85 > >> [<c03b0033>] rpc_wake_up+0x3/0x70 > > It was the only semi-plausible explanation I could come up with. I added a > printk in do_exit right before exit_task_namespaces, where sighand was > still set, and one right before the spin_lock_irq in lockd_down, where it > had suddenly been set to NULL. I can't reproduce the problem, but do_exit: exit_notify(tsk); exit_task_namespaces(tsk); the task could be reaped by its parent in between. We should not use ->signal/->sighand after exit_notify(). Can we move exit_task_namespaces() up? Oleg.
