Re: [PATCH] xencommons: kill xenstored when stop xencommons

[Yu Zhiguo <yuzg@cn.fujitsu.com>]

Hi,

Yu Zhiguo wrote:
> xenstored should be killed when stop xencommons.
> 

>  do_stop () {
> +	if read 2>/dev/null <$XENSTORED_PIDFILE pid; then
> +		kill $pid
> +		while kill -9 $pid >/dev/null 2>&1; do sleep 0.1; done
> +		rm -f $XENSTORED_PIDFILE
> +	fi
> +


It seems that kill xenstored will get taint message about
'HARDIRQ-safe -> HARDIRQ-unsafe'.
Maybe some fix is needed here...


# service xencommons start
# cat /var/run/xenstore.pid
1446
# kill -9 1446


Jun 22 22:51:10 localhost kernel: ======================================================
Jun 22 22:51:10 localhost kernel: [ INFO: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected ]
Jun 22 22:51:10 localhost kernel: 2.6.31.13 #2
Jun 22 22:51:10 localhost kernel: ------------------------------------------------------
Jun 22 22:51:10 localhost kernel: xenstored/1446 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
Jun 22 22:51:10 localhost kernel: (proc_subdir_lock){+.+...}, at: [<ffffffff8119c60f>] xlate_proc_name+0x4c/0xde
Jun 22 22:51:10 localhost kernel:
Jun 22 22:51:10 localhost kernel: and this task is already holding:
Jun 22 22:51:10 localhost kernel: (&port_user_lock){-.....}, at: [<ffffffff8131d3fe>] evtchn_release+0x3a/0xb8
Jun 22 22:51:10 localhost kernel: which would create a new lock dependency:
Jun 22 22:51:10 localhost kernel: (&port_user_lock){-.....} -> (proc_subdir_lock){+.+...}
Jun 22 22:51:10 localhost kernel:
Jun 22 22:51:10 localhost kernel: but this new dependency connects a HARDIRQ-irq-safe lock:
Jun 22 22:51:10 localhost kernel: (&port_user_lock){-.....}
Jun 22 22:51:10 localhost kernel: ... which became HARDIRQ-irq-safe at:
Jun 22 22:51:10 localhost kernel:  [<ffffffff8109915d>] __lock_acquire+0x254/0xc0e
Jun 22 22:51:10 localhost kernel:  [<ffffffff81099c05>] lock_acquire+0xee/0x12e
Jun 22 22:51:10 localhost kernel:  [<ffffffff81521f7f>] _spin_lock+0x45/0x8e
Jun 22 22:51:10 localhost kernel:  [<ffffffff8131dbfd>] evtchn_interrupt+0x3a/0x13f
Jun 22 22:51:10 localhost kernel:  [<ffffffff810c7dd4>] handle_IRQ_event+0x62/0x148
Jun 22 22:51:10 localhost kernel:  [<ffffffff810ca367>] handle_level_irq+0x90/0xf9
Jun 22 22:51:10 localhost kernel:  [<ffffffff813151f1>] xen_evtchn_do_upcall+0x120/0x1c7
Jun 22 22:51:10 localhost kernel:  [<ffffffff8101637e>] xen_do_hypervisor_callback+0x1e/0x30
Jun 22 22:51:10 localhost kernel:  [<ffffffffffffffff>] 0xffffffffffffffff
Jun 22 22:51:10 localhost kernel:
Jun 22 22:51:10 localhost kernel: to a HARDIRQ-irq-unsafe lock:
Jun 22 22:51:10 localhost kernel: (proc_subdir_lock){+.+...}
Jun 22 22:51:10 localhost kernel: ... which became HARDIRQ-irq-unsafe at:
Jun 22 22:51:10 localhost kernel: ...  [<ffffffff810991d1>] __lock_acquire+0x2c8/0xc0e
Jun 22 22:51:10 localhost kernel:  [<ffffffff81099c05>] lock_acquire+0xee/0x12e
Jun 22 22:51:10 localhost kernel:  [<ffffffff81521f7f>] _spin_lock+0x45/0x8e
Jun 22 22:51:10 localhost kernel:  [<ffffffff8119c60f>] xlate_proc_name+0x4c/0xde
Jun 22 22:51:10 localhost kernel:  [<ffffffff8119d370>] __proc_create+0x53/0x148
Jun 22 22:51:10 localhost kernel:  [<ffffffff8119d75d>] proc_symlink+0x3e/0xc5
Jun 22 22:51:10 localhost kernel:  [<ffffffff81a49c03>] proc_root_init+0x75/0xe0
Jun 22 22:51:10 localhost kernel:  [<ffffffff81a2063b>] start_kernel+0x403/0x44c
Jun 22 22:51:10 localhost kernel:  [<ffffffff81a1f930>] x86_64_start_reservations+0xbb/0xd6
Jun 22 22:51:10 localhost kernel:  [<ffffffff81a23e98>] xen_start_kernel+0x5e3/0x5ea
Jun 22 22:51:10 localhost kernel:  [<ffffffffffffffff>] 0xffffffffffffffff
Jun 22 22:51:10 localhost kernel:
Jun 22 22:51:10 localhost kernel: other info that might help us debug this:
...