Re: [PATCH] uprobes: Use better bitmap_zalloc()

[kernel test robot]

Hi Kefeng,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tip/perf/core]
[also build test WARNING on linux/master linus/master v5.13-rc3 next-20210528]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Kefeng-Wang/uprobes-Use-better-bitmap_zalloc/20210529-190812
base:   https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 875dd7bf548104bc1d2c5784a6af6cf38215a216
config: x86_64-randconfig-a006-20210529 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project bc6799f2f79f0ae87e9f1ebf9d25ba799fbd25a9)
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 x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/346b85395aa484f7b3b64a53e197bc7f56a4e719
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Kefeng-Wang/uprobes-Use-better-bitmap_zalloc/20210529-190812
        git checkout 346b85395aa484f7b3b64a53e197bc7f56a4e719
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

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

All warnings (new ones prefixed by >>):

   kernel/events/uprobes.c:1490:17: error: implicit declaration of function 'bitmap_kzalloc' [-Werror,-Wimplicit-function-declaration]
           area->bitmap = bitmap_kzalloc(UINSNS_PER_PAGE, GFP_KERNEL);
                          ^
   kernel/events/uprobes.c:1490:17: note: did you mean 'bitmap_zalloc'?
   include/linux/bitmap.h:125:16: note: 'bitmap_zalloc' declared here
   unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
                  ^
>> kernel/events/uprobes.c:1490:15: warning: incompatible integer to pointer conversion assigning to 'unsigned long *' from 'int' [-Wint-conversion]
           area->bitmap = bitmap_kzalloc(UINSNS_PER_PAGE, GFP_KERNEL);
                        ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   kernel/events/uprobes.c:1514:2: error: implicit declaration of function 'bitmap_kfree' [-Werror,-Wimplicit-function-declaration]
           bitmap_kfree(area->bitmap);
           ^
   kernel/events/uprobes.c:1514:2: note: did you mean 'bitmap_free'?
   include/linux/bitmap.h:126:6: note: 'bitmap_free' declared here
   void bitmap_free(const unsigned long *bitmap);
        ^
   kernel/events/uprobes.c:1555:2: error: implicit declaration of function 'bitmap_kfree' [-Werror,-Wimplicit-function-declaration]
           bitmap_kfree(area->bitmap);
           ^
   1 warning and 3 errors generated.


vim +1490 kernel/events/uprobes.c

  1479	
  1480	static struct xol_area *__create_xol_area(unsigned long vaddr)
  1481	{
  1482		struct mm_struct *mm = current->mm;
  1483		uprobe_opcode_t insn = UPROBE_SWBP_INSN;
  1484		struct xol_area *area;
  1485	
  1486		area = kmalloc(sizeof(*area), GFP_KERNEL);
  1487		if (unlikely(!area))
  1488			goto out;
  1489	
> 1490		area->bitmap = bitmap_kzalloc(UINSNS_PER_PAGE, GFP_KERNEL);
  1491		if (!area->bitmap)
  1492			goto free_area;
  1493	
  1494		area->xol_mapping.name = "[uprobes]";
  1495		area->xol_mapping.fault = NULL;
  1496		area->xol_mapping.pages = area->pages;
  1497		area->pages[0] = alloc_page(GFP_HIGHUSER);
  1498		if (!area->pages[0])
  1499			goto free_bitmap;
  1500		area->pages[1] = NULL;
  1501	
  1502		area->vaddr = vaddr;
  1503		init_waitqueue_head(&area->wq);
  1504		/* Reserve the 1st slot for get_trampoline_vaddr() */
  1505		set_bit(0, area->bitmap);
  1506		atomic_set(&area->slot_count, 1);
  1507		arch_uprobe_copy_ixol(area->pages[0], 0, &insn, UPROBE_SWBP_INSN_SIZE);
  1508	
  1509		if (!xol_add_vma(mm, area))
  1510			return area;
  1511	
  1512		__free_page(area->pages[0]);
  1513	 free_bitmap:
  1514		bitmap_kfree(area->bitmap);
  1515	 free_area:
  1516		kfree(area);
  1517	 out:
  1518		return NULL;
  1519	}
  1520	

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

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