[PATCH v8 0/8] livepatch: Atomic replace feature

[Petr Mladek <pmladek@suse.com>]

The atomic replace allows to create cumulative patches. They
are useful when you maintain many livepatches and want to remove
one that is lower on the stack. In addition it is very useful when
more patches touch the same function and there are dependencies
between them.

I have found one bug in v7. We were not able to initialize NOP
struct klp_func when the patches module is not loaded. It was
because func->new_func was NULL. I have fixed it in separate patch
for an easier review.

Note that the original Jason's patch did not have this problem
because func->new_func was always NULL there. But this required
NOP-specific handling also on other locations, namely
klp_ftrace_handler() and klp_check_stack_func().

Changes against v7:

  + Fixed handling of NOPs for not-yet-loaded modules
  + Made klp_replaced_patches list static [Mirek]
  + Made klp_free_object() public later [Mirek]
  + Fixed several reported typos [Mirek, Joe]
  + Updated documentation according to the feedback [Joe]
  + Added some Acks [Mirek]

Changes against v6:

  + used list_move when disabling replaced patches [Jason]
  + renamed KLP_FUNC_ORIGINAL -> KLP_FUNC_STATIC [Mirek]
  + used klp_is_func_type() in klp_unpatch_object() [Mirek]
  + moved static definition of klp_get_or_add_object() [Mirek]
  + updated comment about synchronization in forced mode [Mirek]
  + added user documentation
  + fixed several typos

Jason Baron (5):
  livepatch: Use lists to manage patches, objects and functions
  livepatch: Initial support for dynamic structures
  livepatch: Allow to unpatch only functions of the given type
  livepatch: Support separate list for replaced patches.
  livepatch: Add atomic replace

Petr Mladek (3):
  livepatch: Free only structures with initialized kobject
  livepatch: Correctly handle atomic replace for not yet loaded modules
  livepatch: Atomic replace and cumulative patches documentation

 Documentation/livepatch/cumulative-patches.txt |  83 ++++++
 include/linux/livepatch.h                      |  59 +++-
 kernel/livepatch/core.c                        | 394 ++++++++++++++++++++++---
 kernel/livepatch/core.h                        |   4 +
 kernel/livepatch/patch.c                       |  31 +-
 kernel/livepatch/patch.h                       |   4 +-
 kernel/livepatch/transition.c                  |  41 ++-
 7 files changed, 566 insertions(+), 50 deletions(-)
 create mode 100644 Documentation/livepatch/cumulative-patches.txt

-- 
2.13.6