All of lore.kernel.org
 help / color / mirror / Atom feed
From: Rong Chen <rong.a.chen@intel.com>
To: Andy Shevchenko <andy.shevchenko@gmail.com>,
	kernel test robot <lkp@intel.com>
Cc: Syed Nayyar Waris <syednwaris@gmail.com>,
	kbuild-all@lists.01.org,
	"open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [kbuild-all] Re: [gpio:ib-for-each-clump 4/4] include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
Date: Fri, 17 Jul 2020 15:14:46 +0800	[thread overview]
Message-ID: <4cd8eb7e-f21f-29a7-08ab-c691c1260c55@intel.com> (raw)
In-Reply-To: <CAHp75VezG1ZnC-1UWea2Q-q-=c_32HOcBTXrd7cy4HzB-uW8JA@mail.gmail.com>



On 7/17/20 5:25 AM, Andy Shevchenko wrote:
> On Thu, Jul 16, 2020 at 11:13 PM kernel test robot <lkp@intel.com> wrote:
>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git ib-for-each-clump
>> head:   3358c938236d6a1be51124fbbb2698e50689d382
>> commit: 3358c938236d6a1be51124fbbb2698e50689d382 [4/4] gpio: xilinx: Utilize generic bitmap_get_value and _set_value.
>> config: alpha-randconfig-s031-20200716 (attached as .config)
>> compiler: alpha-linux-gcc (GCC) 9.3.0
>> reproduce:
>>          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>>          chmod +x ~/bin/make.cross
>>          # apt-get install sparse
>>          # sparse version: v0.6.2-49-g707c5017-dirty
>>          git checkout 3358c938236d6a1be51124fbbb2698e50689d382
>>          # save the attached .config to linux build tree
>>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=alpha
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>>
>> sparse warnings: (new ones prefixed by >>)
>>
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>     include/linux/bitmap.h:594:63: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:638:17: sparse: sparse: invalid access past the end of 'old' (8 8)
>> vim +639 include/linux/bitmap.h
>>
>> 169c474fb22d8a5 William Breathitt Gray 2019-12-04  613
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  614  /**
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  615   * bitmap_set_value - set n-bit value within a memory region
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  616   * @map: address to the bitmap memory region
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  617   * @value: value of nbits
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  618   * @start: bit offset of the n-bit value
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  619   * @nbits: size of value in bits
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  620   */
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  621  static inline void bitmap_set_value(unsigned long *map,
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  622                                      unsigned long value,
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  623                                      unsigned long start, unsigned long nbits)
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  624  {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  625          const size_t index = BIT_WORD(start);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  626          const unsigned long offset = start % BITS_PER_LONG;
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  627          const unsigned long ceiling = roundup(start + 1, BITS_PER_LONG);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  628          const unsigned long space = ceiling - start;
> If start == 0:
>    index = 0, offset = 0, ceiling = 64, space = 64
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  629
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  630          value &= GENMASK(nbits - 1, 0);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  631
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  632          if (space >= nbits) {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  633                  map[index] &= ~(GENMASK(nbits + offset - 1, offset));
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  634                  map[index] |= value << offset;
> if nbits > space...
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  635          } else {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  636                  map[index] &= ~BITMAP_FIRST_WORD_MASK(start);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  637                  map[index] |= value << offset;
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @638                  map[index + 1] &= ~BITMAP_LAST_WORD_MASK(start + nbits);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @639                  map[index + 1] |= (value >> space);
> space = 64...
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  640          }
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  641  }
> I don't see the test case for this. Can you provide one?
>
>

Hi Andy,

Sparse doesn't check the if condition, it found the issues related to 
the below two lines
when bitmap_set_value was first time used in this commit.

e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @638                  map[index + 1] &= ~BITMAP_LAST_WORD_MASK(start + nbits);
e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @639                  map[index + 1] |= (value >> space);

Best Regards,
Rong Chen


WARNING: multiple messages have this Message-ID (diff)
From: Rong Chen <rong.a.chen@intel.com>
To: kbuild-all@lists.01.org
Subject: Re: [gpio:ib-for-each-clump 4/4] include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
Date: Fri, 17 Jul 2020 15:14:46 +0800	[thread overview]
Message-ID: <4cd8eb7e-f21f-29a7-08ab-c691c1260c55@intel.com> (raw)
In-Reply-To: <CAHp75VezG1ZnC-1UWea2Q-q-=c_32HOcBTXrd7cy4HzB-uW8JA@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 5176 bytes --]



On 7/17/20 5:25 AM, Andy Shevchenko wrote:
> On Thu, Jul 16, 2020 at 11:13 PM kernel test robot <lkp@intel.com> wrote:
>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio.git ib-for-each-clump
>> head:   3358c938236d6a1be51124fbbb2698e50689d382
>> commit: 3358c938236d6a1be51124fbbb2698e50689d382 [4/4] gpio: xilinx: Utilize generic bitmap_get_value and _set_value.
>> config: alpha-randconfig-s031-20200716 (attached as .config)
>> compiler: alpha-linux-gcc (GCC) 9.3.0
>> reproduce:
>>          wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>>          chmod +x ~/bin/make.cross
>>          # apt-get install sparse
>>          # sparse version: v0.6.2-49-g707c5017-dirty
>>          git checkout 3358c938236d6a1be51124fbbb2698e50689d382
>>          # save the attached .config to linux build tree
>>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=alpha
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>>
>> sparse warnings: (new ones prefixed by >>)
>>
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>     include/linux/bitmap.h:594:63: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long
>>>> include/linux/bitmap.h:638:17: sparse: sparse: invalid access past the end of 'old' (8 8)
>> vim +639 include/linux/bitmap.h
>>
>> 169c474fb22d8a5 William Breathitt Gray 2019-12-04  613
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  614  /**
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  615   * bitmap_set_value - set n-bit value within a memory region
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  616   * @map: address to the bitmap memory region
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  617   * @value: value of nbits
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  618   * @start: bit offset of the n-bit value
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  619   * @nbits: size of value in bits
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  620   */
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  621  static inline void bitmap_set_value(unsigned long *map,
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  622                                      unsigned long value,
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  623                                      unsigned long start, unsigned long nbits)
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  624  {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  625          const size_t index = BIT_WORD(start);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  626          const unsigned long offset = start % BITS_PER_LONG;
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  627          const unsigned long ceiling = roundup(start + 1, BITS_PER_LONG);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  628          const unsigned long space = ceiling - start;
> If start == 0:
>    index = 0, offset = 0, ceiling = 64, space = 64
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  629
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  630          value &= GENMASK(nbits - 1, 0);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  631
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  632          if (space >= nbits) {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  633                  map[index] &= ~(GENMASK(nbits + offset - 1, offset));
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  634                  map[index] |= value << offset;
> if nbits > space...
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  635          } else {
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  636                  map[index] &= ~BITMAP_FIRST_WORD_MASK(start);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  637                  map[index] |= value << offset;
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @638                  map[index + 1] &= ~BITMAP_LAST_WORD_MASK(start + nbits);
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @639                  map[index + 1] |= (value >> space);
> space = 64...
>
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  640          }
>> e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27  641  }
> I don't see the test case for this. Can you provide one?
>
>

Hi Andy,

Sparse doesn't check the if condition, it found the issues related to 
the below two lines
when bitmap_set_value was first time used in this commit.

e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @638                  map[index + 1] &= ~BITMAP_LAST_WORD_MASK(start + nbits);
e77c9b6f35c4bdf Syed Nayyar Waris      2020-06-27 @639                  map[index + 1] |= (value >> space);

Best Regards,
Rong Chen

  parent reply	other threads:[~2020-07-17  7:15 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-16 19:48 [gpio:ib-for-each-clump 4/4] include/linux/bitmap.h:639:45: sparse: sparse: shift too big (64) for type unsigned long kernel test robot
2020-07-16 19:48 ` kernel test robot
2020-07-16 21:25 ` Andy Shevchenko
2020-07-16 21:25   ` Andy Shevchenko
2020-07-17  4:49   ` Syed Nayyar Waris
2020-07-17  7:14   ` Rong Chen [this message]
2020-07-17  7:14     ` Rong Chen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4cd8eb7e-f21f-29a7-08ab-c691c1260c55@intel.com \
    --to=rong.a.chen@intel.com \
    --cc=andy.shevchenko@gmail.com \
    --cc=kbuild-all@lists.01.org \
    --cc=linus.walleij@linaro.org \
    --cc=linux-gpio@vger.kernel.org \
    --cc=lkp@intel.com \
    --cc=syednwaris@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.