Re: [PATCH 3/3] vmalloc: Add debugfs modfraginfo

[kbuild test robot]

Hi Rick,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v4.18-rc5]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Rick-Edgecombe/KASLR-feature-to-randomize-each-loadable-module/20180707-083637
config: um-allmodconfig (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=um 

All errors (new ones prefixed by >>):

   mm/vmalloc.c: In function 'modulefraginfo_debug_show':
>> mm/vmalloc.c:2964:41: error: 'MODULES_RAND_LEN' undeclared (first use in this function); did you mean 'MODULE_NAME_LEN'?
       if (obj->va_start >= MODULES_VADDR + MODULES_RAND_LEN)
                                            ^~~~~~~~~~~~~~~~
                                            MODULE_NAME_LEN
   mm/vmalloc.c:2964:41: note: each undeclared identifier is reported only once for each function it appears in

vim +2964 mm/vmalloc.c

  2933	
  2934	#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_X86_64)
  2935	#if defined(CONFIG_RANDOMIZE_BASE)
  2936	static void print_backup_area(struct seq_file *m, unsigned long backup_cnt)
  2937	{
  2938		if (kaslr_enabled())
  2939			seq_printf(m, "Allocations in backup area:\t%lu\n", backup_cnt);
  2940	}
  2941	#else
  2942	static void print_backup_area(struct seq_file *m, unsigned long backup_cnt)
  2943	{
  2944	}
  2945	#endif
  2946	static int modulefraginfo_debug_show(struct seq_file *m, void *v)
  2947	{
  2948		struct list_head *i;
  2949		unsigned long last_end = MODULES_VADDR;
  2950		unsigned long total_free = 0;
  2951		unsigned long largest_free = 0;
  2952		unsigned long backup_cnt = 0;
  2953		unsigned long gap;
  2954	
  2955		spin_lock(&vmap_area_lock);
  2956	
  2957		list_for_each(i, &vmap_area_list) {
  2958			struct vmap_area *obj = list_entry(i, struct vmap_area, list);
  2959	
  2960			if (!(obj->flags & VM_LAZY_FREE)
  2961				&& obj->va_start >= MODULES_VADDR
  2962				&& obj->va_end <= MODULES_END) {
  2963	
> 2964				if (obj->va_start >= MODULES_VADDR + MODULES_RAND_LEN)
  2965					backup_cnt++;
  2966	
  2967				gap = (obj->va_start - last_end);
  2968				if (gap > largest_free)
  2969					largest_free = gap;
  2970				total_free += gap;
  2971	
  2972				last_end = obj->va_end;
  2973			}
  2974		}
  2975	
  2976		gap = (MODULES_END - last_end);
  2977		if (gap > largest_free)
  2978			largest_free = gap;
  2979		total_free += gap;
  2980	
  2981		spin_unlock(&vmap_area_lock);
  2982	
  2983		seq_printf(m, "Largest free space:\t\t%lu\n", largest_free);
  2984		if (total_free)
  2985			seq_printf(m, "External Memory Fragmentation:\t%lu%%\n",
  2986				100-(100*largest_free/total_free));
  2987		else
  2988			seq_puts(m, "External Memory Fragmentation:\t0%%\n");
  2989	
  2990		print_backup_area(m, backup_cnt);
  2991	
  2992		return 0;
  2993	}
  2994	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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