[PATCH 0/2] livepatch: introduce 'stack_order' sysfs interface to klp_patch

[Wardenjohn]

As previous discussion, maintainers think that patch-level sysfs interface is the
only acceptable way to maintain the information of the order that klp_patch is 
applied to the system.

However, the previous patch introduce klp_ops into klp_func is a optimization 
methods of the patch introducing 'using' feature to klp_func.

But now, we don't support 'using' feature to klp_func and make 'klp_ops' patch
not necessary.

Therefore, this new version is only introduce the sysfs feature of klp_patch 
'stack_order'.

V1 -> V2:
1. According to the suggestion from Petr, to make the meaning more clear, rename
'order' to 'stack_order'.
2. According to the suggestion from Petr and Miroslav, this patch now move the 
calculating process to stack_order_show function. Adding klp_mutex lock protection.

Regards.
Wardenjohn.