From cfee9eddcd61e28b73468647fc4aa7ff2d706254 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Thu, 6 Oct 2016 00:28:40 -0500 Subject: 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: Karl Beldan Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: Frederic Weisbecker Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: ec2ad9ccf12d ("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: Ingo Molnar --- arch/x86/kernel/unwind_guess.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/x86/kernel/unwind_guess.c') diff --git a/arch/x86/kernel/unwind_guess.c b/arch/x86/kernel/unwind_guess.c index b5a834c93065..9298993dc8b7 100644 --- a/arch/x86/kernel/unwind_guess.c +++ b/arch/x86/kernel/unwind_guess.c @@ -5,6 +5,16 @@ #include #include +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; -- cgit v1.2.3-59-g8ed1b