Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livep...

Pull livepatching updates from Jiri Kosina:

 - removal of dead code (Kamalesh Babulal)

 - documentation update (Miroslav Benes)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: doc: remove the limitation for schedule() patching
  powerpc/livepatch: Remove klp_write_module_reloc() stub

diff --git a/Documentation/livepatch/livepatch.txt b/Documentation/livepatch/livepatch.txt
index f5967316deb9fd38462c3de20620e23bb4fb1860..7f04e13ec53d80189553fefd90dcfca135c6d205 100644 (file)
--- a/Documentation/livepatch/livepatch.txt
+++ b/Documentation/livepatch/livepatch.txt
@@ -329,25 +329,6 @@ The current Livepatch implementation has several limitations:
     by "notrace".
 
 
-  + Anything inlined into __schedule() can not be patched.
-
-    The switch_to macro is inlined into __schedule(). It switches the
-    context between two processes in the middle of the macro. It does
-    not save RIP in x86_64 version (contrary to 32-bit version). Instead,
-    the currently used __schedule()/switch_to() handles both processes.
-
-    Now, let's have two different tasks. One calls the original
-    __schedule(), its registers are stored in a defined order and it
-    goes to sleep in the switch_to macro and some other task is restored
-    using the original __schedule(). Then there is the second task which
-    calls patched__schedule(), it goes to sleep there and the first task
-    is picked by the patched__schedule(). Its RSP is restored and now
-    the registers should be restored as well. But the order is different
-    in the new patched__schedule(), so...
-
-    There is work in progress to remove this limitation.
-
-
   + Livepatch modules can not be removed.
 
     The current implementation just redirects the functions at the very

diff --git a/arch/powerpc/include/asm/livepatch.h b/arch/powerpc/include/asm/livepatch.h
index a402f7f948965f1f28d4c3f2385001c1ecdef2b6..47a03b9b528b46672ece81b641ebecc13247c817 100644 (file)
--- a/arch/powerpc/include/asm/livepatch.h
+++ b/arch/powerpc/include/asm/livepatch.h
@@ -28,13 +28,6 @@ static inline int klp_check_compiler_support(void)
        return 0;
 }
 
-static inline int klp_write_module_reloc(struct module *mod, unsigned long
-               type, unsigned long loc, unsigned long value)
-{
-       /* This requires infrastructure changes; we need the loadinfos. */
-       return -ENOSYS;
-}
-
 static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip)
 {
        regs->nip = ip;