[hnaz-mm:master 29/122] arch/arm64/kernel/stacktrace.c:289:13: error: implicit declaration of function 'task_scs' is invalid in C99

[hnaz-mm:master 29/122] arch/arm64/kernel/stacktrace.c:289:13: error: implicit declaration of function 'task_scs' is invalid in C99

[kernel test robot]

tree:   https://github.com/hnaz/linux-mm master
head:   074b4ea9811e2c47ae1ecada177629c19fa56d59
commit: 8cdc580c5ca2ffecb0db4f84a99167ef763a21cc [29/122] arm64: implement stack_trace_save_shadow
config: arm64-randconfig-r012-20220331 (https://download.01.org/0day-ci/archive/20220331/202203312049.zLjHyetm-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 881350a92d821d4f8e4fa648443ed1d17e251188)
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
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/hnaz/linux-mm/commit/8cdc580c5ca2ffecb0db4f84a99167ef763a21cc
        git remote add hnaz-mm https://github.com/hnaz/linux-mm
        git fetch --no-tags hnaz-mm master
        git checkout 8cdc580c5ca2ffecb0db4f84a99167ef763a21cc
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash arch/arm64/kernel/

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

All error/warnings (new ones prefixed by >>):

>> arch/arm64/kernel/stacktrace.c:289:13: error: implicit declaration of function 'task_scs' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
           scs_base = task_scs(current);
                      ^
>> arch/arm64/kernel/stacktrace.c:289:11: warning: incompatible integer to pointer conversion assigning to 'unsigned long *' from 'int' [-Wint-conversion]
           scs_base = task_scs(current);
                    ^ ~~~~~~~~~~~~~~~~~
   1 warning and 1 error generated.


vim +/task_scs +289 arch/arm64/kernel/stacktrace.c

   260	
   261	noinline notrace int arch_stack_walk_shadow(unsigned long *store,
   262						    unsigned int size,
   263						    unsigned int skipnr)
   264	{
   265		unsigned long *scs_top, *scs_base, *scs_next;
   266		unsigned int len = 0, part;
   267	
   268		preempt_disable();
   269	
   270		/* Get the SCS pointer. */
   271		asm volatile("mov %0, x18" : "=&r" (scs_top));
   272	
   273		/* The top SCS slot is empty. */
   274		scs_top -= 1;
   275	
   276		/* Handle SDEI and hardirq frames. */
   277		for (part = 0; part < ARRAY_SIZE(scs_parts); part++) {
   278			scs_next = *this_cpu_ptr(scs_parts[part].saved);
   279			if (scs_next) {
   280				scs_base = *this_cpu_ptr(scs_parts[part].base);
   281				if (walk_shadow_stack_part(scs_top, scs_base, store,
   282							   size, &skipnr, &len))
   283					goto out;
   284				scs_top = scs_next;
   285			}
   286		}
   287	
   288		/* Handle task and softirq frames. */
 > 289		scs_base = task_scs(current);

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [hnaz-mm:master 29/122] arch/arm64/kernel/stacktrace.c:289:13: error: implicit declaration of function 'task_scs' is invalid in C99

[Andrew Morton]

On Thu, 31 Mar 2022 20:59:49 +0800 kernel test robot <lkp@intel.com> wrote:

> >> arch/arm64/kernel/stacktrace.c:289:13: error: implicit declaration of function 'task_scs' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
>            scs_base = task_scs(current);
>                       ^

Thanks.   Presumably this:

--- a/arch/arm64/kernel/stacktrace.c~arm64-implement-stack_trace_save_shadow-fix
+++ a/arch/arm64/kernel/stacktrace.c
@@ -213,6 +213,7 @@ noinline notrace void arch_stack_walk(st
 	walk_stackframe(task, &frame, consume_entry, cookie);
 }
 
+#ifdef CONFIG_SHADOW_CALL_STACK
 static const struct {
 	unsigned long ** __percpu saved;
 	unsigned long ** __percpu base;
@@ -293,3 +294,4 @@ out:
 	preempt_enable();
 	return len;
 }
+#endif		/* CONFIG_SHADOW_CALL_STACK */
_