Hi Masami,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.19.y
head:   5a3ba2f90f8789162a03e07a37224bab4c643d1d
commit: d3380de483d55d904fb94a241406b34ed2fada7d [1864/4040] ia64: kprobes: Use generic kretprobe trampoline handler
config: ia64-allmodconfig (attached as .config)
compiler: ia64-linux-gcc (GCC) 10.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git/commit/?id=d3380de483d55d904fb94a241406b34ed2fada7d
        git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git
        git fetch --no-tags linux-stable-rc linux-4.19.y
        git checkout d3380de483d55d904fb94a241406b34ed2fada7d
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross ARCH=ia64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   arch/ia64/kernel/kprobes.c: In function 'get_kprobe_inst':
   arch/ia64/kernel/kprobes.c:338:15: warning: variable 'template' set but not used [-Wunused-but-set-variable]
     338 |  unsigned int template;
         |               ^~~~~~~~
   arch/ia64/kernel/kprobes.c: At top level:
   arch/ia64/kernel/kprobes.c:412:15: warning: no previous prototype for 'trampoline_probe_handler' [-Wmissing-prototypes]
     412 | int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
         |               ^~~~~~~~~~~~~~~~~~~~~~~~
   arch/ia64/kernel/kprobes.c: In function 'trampoline_probe_handler':
>> arch/ia64/kernel/kprobes.c:414:17: error: implicit declaration of function '__kretprobe_trampoline_handler'; did you mean 'kretprobe_trampoline'? [-Werror=implicit-function-declaration]
     414 |  regs->cr_iip = __kretprobe_trampoline_handler(regs, kretprobe_trampoline, NULL);
         |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
         |                 kretprobe_trampoline
   At top level:
   arch/ia64/kernel/kprobes.c:928:13: warning: 'ia64_get_bsp_cfm' defined but not used [-Wunused-function]
     928 | static void ia64_get_bsp_cfm(struct unw_frame_info *info, void *arg)
         |             ^~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for FRAME_POINTER
   Depends on DEBUG_KERNEL && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS
   Selected by
   - FAULT_INJECTION_STACKTRACE_FILTER && FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT && !X86_64 && !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC && !X86


vim +414 arch/ia64/kernel/kprobes.c

   411	
   412	int __kprobes trampoline_probe_handler(struct kprobe *p, struct pt_regs *regs)
   413	{
 > 414		regs->cr_iip = __kretprobe_trampoline_handler(regs, kretprobe_trampoline, NULL);
   415		/*
   416		 * By returning a non-zero value, we are telling
   417		 * kprobe_handler() that we don't want the post_handler
   418		 * to run (and have re-enabled preemption)
   419		 */
   420		return 1;
   421	}
   422	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org