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

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
Linus Torvalds 8 tahun lalu
induk
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59da2a0630

+ 0 - 19
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

+ 0 - 7
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;