Hi Slava,

kernel test robot noticed the following build errors:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/intel-lab-lkp/linux/commits/Slava-Imameev/bpf-Support-multi-level-pointer-params-via-PTR_TO_MEM-for-trampolines/20260218-062417
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20260217221357.18215-3-slava.imameev%40crowdstrike.com
patch subject: [PATCH bpf-next v2 2/2] selftests/bpf: Add trampolines multi-level pointer params test coverage
config: loongarch-defconfig (https://download.01.org/0day-ci/archive/20260218/202602181710.tEK6nOl6-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260218/202602181710.tEK6nOl6-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot [off-list ref]
| Closes: https://lore.kernel.org/oe-kbuild-all/202602181710.tEK6nOl6-lkp@intel.com/ (local)

All errors (new ones prefixed by >>):

quoted

net/bpf/test_run.c:737:2: error: call to undeclared function 'flush_tlb_kernel_range'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]

     737 |         flush_tlb_kernel_range((unsigned long)page_address(page),
         |         ^
   net/bpf/test_run.c:760:2: error: call to undeclared function 'flush_tlb_kernel_range'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     760 |         flush_tlb_kernel_range((unsigned long)addr,
         |         ^
   2 errors generated.


vim +/flush_tlb_kernel_range +737 net/bpf/test_run.c

   709	
   710	static void *create_bad_kaddr(void)
   711	{
   712		/*
   713		 * Try to get an address that passes kernel range checks but causes
   714		 * a page fault handler invocation if accessed from a BPF program.
   715		 */
   716	#if defined(CONFIG_ARCH_HAS_SET_MEMORY) && defined(CONFIG_X86)
   717		void *addr = vmalloc(PAGE_SIZE);
   718	
   719		if (!addr)
   720			return NULL;
   721		/* Make it non-present - any access will fault */
   722		if (set_memory_np((unsigned long)addr, 1)) {
   723			vfree(addr);
   724			return NULL;
   725		}
   726		return addr;
   727	#elif defined(CONFIG_ARCH_HAS_SET_DIRECT_MAP)
   728		struct page *page = alloc_page(GFP_KERNEL);
   729	
   730		if (!page)
   731			return NULL;
   732		/* Remove from direct map - any access will fault */
   733		if (set_direct_map_invalid_noflush(page)) {
   734			__free_page(page);
   735			return NULL;
   736		}
 > 737		flush_tlb_kernel_range((unsigned long)page_address(page),
   738				       (unsigned long)page_address(page) + PAGE_SIZE);
   739		return page_address(page);
   740	#endif
   741		return NULL;
   742	}
   743	

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