x86/ftrace: Exclude functions in head64.c from function-tracing
authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tue, 27 Jun 2017 11:59:48 +0000 (14:59 +0300)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 29 Jun 2017 20:33:27 +0000 (22:33 +0200)
commitbb43dbc5e09d52c6085dfee65f4f923b3fbcd1d4
treebaec04e7292e9bca897ad52922d77d39ad31305e
parent4a06370bcb674af88679a4f2c5c87c3e40688935
x86/ftrace: Exclude functions in head64.c from function-tracing

A recent commit moved most logic of early boot up from startup_64() written
in assembly to __startup_64() written in C.

Fengguang reported breakage due to the change. It was tracked down to
CONFIG_FUNCTION_TRACER being enabled.

Tracing this function is not possible because it's invoked from the
earliest boot stage before the relocation fixups have been done. It is the
function doing the relocation.

Exclude it from being built with tracer stubs.

Fixes: c88d71508e36 ("x86/boot/64: Rewrite startup_64() in C")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: lkp@01.org
Link: http://lkml.kernel.org/r/20170627115948.17938-1-kirill.shutemov@linux.intel.com
arch/x86/kernel/Makefile