Re: powerpc ftrace broken due to "manual merge of the ftrace tree with the arm64 tree"

[Steven Rostedt]

On Fri, 15 Nov 2019 16:06:34 -0500
Qian Cai <c...@lca.pw> wrote:

> > Test this commit please: b83b43ffc6e4b514ca034a0fbdee01322e2f7022  
> 
> # git reset --hard b83b43ffc6e4b514ca034a0fbdee01322e2f7022
> 
> Yes, that one is bad.

Can you see if this patch fixes the issue for you?

Thanks!

-- Steve

diff --git a/include/asm-generic/vmlinux.lds.h 
b/include/asm-generic/vmlinux.lds.h
index 0f358be551cd..fd8f4dc661dc 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -109,6 +109,13 @@
 #define MEM_DISCARD(sec) *(.mem##sec)
 #endif
 
+/* PowerPC defines ftrace_graph_stub in the code */
+#ifndef CONFIG_PPC
+# define DEFINE_FTRACE_GRAPH_STUB      ftrace_graph_stub = ftrace_stub;
+#else
+# define DEFINE_FTRACE_GRAPH_STUB
+#endif
+
 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 #ifdef CC_USING_PATCHABLE_FUNCTION_ENTRY
 /*
@@ -120,17 +127,17 @@
                        __start_mcount_loc = .;                 \
                        KEEP(*(__patchable_function_entries))   \
                        __stop_mcount_loc = .;                  \
-                       ftrace_graph_stub = ftrace_stub;
+                       DEFINE_FTRACE_GRAPH_STUB
 #else
 #define MCOUNT_REC()   . = ALIGN(8);                           \
                        __start_mcount_loc = .;                 \
                        KEEP(*(__mcount_loc))                   \
                        __stop_mcount_loc = .;                  \
-                       ftrace_graph_stub = ftrace_stub;
+                       DEFINE_FTRACE_GRAPH_STUB
 #endif
 #else
 # ifdef CONFIG_FUNCTION_TRACER
-#  define MCOUNT_REC() ftrace_graph_stub = ftrace_stub;
+#  define MCOUNT_REC() DEFINE_FTRACE_GRAPH_STUB
 # else
 #  define MCOUNT_REC()
 # endif