Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cfee9edd authored by Josh Poimboeuf's avatar Josh Poimboeuf Committed by Ingo Molnar
Browse files

x86/unwind: Fix oprofile module link error 



When compiling on x86 with CONFIG_OPROFILE=m and CONFIG_FRAME_POINTER=n,
the oprofile module fails to link:

  ERROR: ftrace_graph_ret_addr" [arch/x86/oprofile/oprofile.ko] undefined!

The problem was introduced when oprofile was converted to use the new
x86 unwinder.  When frame pointers are disabled, the "guess" unwinder's
unwind_get_return_address() is an inline function which calls
ftrace_graph_ret_addr(), which is not exported.

Fix it by converting the "guess" version of unwind_get_return_address()
to an exported out-of-line function, just like its frame pointer
counterpart.

Reported-by: default avatarKarl Beldan <karl.beldan@gmail.com>
Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: ec2ad9cc ("oprofile/x86: Convert x86_backtrace() to use the new unwinder")
Link: http://lkml.kernel.org/r/be08d589f6474df78364e081c42777e382af9352.1475731632.git.jpoimboe@redhat.com


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent b91688f5

arch/x86/include/asm/unwind.h

+2 −12
Original line number Diff line number Diff line
@@ -23,6 +23,8 @@ void __unwind_start(struct unwind_state *state, struct task_struct *task, 


bool unwind_next_frame(struct unwind_state *state);



unsigned long unwind_get_return_address(struct unwind_state *state);



static inline bool unwind_done(struct unwind_state *state)

{

	return state->stack_info.type == STACK_TYPE_UNKNOWN;
@@ -48,8 +50,6 @@ unsigned long *unwind_get_return_address_ptr(struct unwind_state *state) 
	return state->bp + 1;

}



unsigned long unwind_get_return_address(struct unwind_state *state);



#else /* !CONFIG_FRAME_POINTER */



static inline
@@ -58,16 +58,6 @@ unsigned long *unwind_get_return_address_ptr(struct unwind_state *state) 
	return NULL;

}



static inline

unsigned long unwind_get_return_address(struct unwind_state *state)

{

	if (unwind_done(state))

		return 0;



	return ftrace_graph_ret_addr(state->task, &state->graph_idx,

				     *state->sp, state->sp);

}



#endif /* CONFIG_FRAME_POINTER */



#endif /* _ASM_X86_UNWIND_H */

arch/x86/kernel/unwind_guess.c

+10 −0
Original line number Diff line number Diff line
@@ -5,6 +5,16 @@ 
#include <asm/stacktrace.h>

#include <asm/unwind.h>



unsigned long unwind_get_return_address(struct unwind_state *state)

{

	if (unwind_done(state))

		return 0;



	return ftrace_graph_ret_addr(state->task, &state->graph_idx,

				     *state->sp, state->sp);

}

EXPORT_SYMBOL_GPL(unwind_get_return_address);



bool unwind_next_frame(struct unwind_state *state)

{

	struct stack_info *info = &state->stack_info;