drivers/media/pci/intel/ipu3/ipu3-cio2.c:163:56: warning: implicit conversion from 'unsigned long' to 'u16' (aka 'unsigned short') changes value from 131072 to 0
8:23 a.m.
tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 27bba9c532a8d21050b94224ffd310ad0058c353
commit: 7b285f41f7376dc37e7fad1e803995fd39f42848 media: ipu3-cio2: Introduce
CIO2_LOP_ENTRIES constant
date: 2 months ago
config: arm64-randconfig-r031-20201121 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project
bec968cbb367dd03439c89c1d4ef968ef662d7c0)
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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit...
git remote add linus
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 7b285f41f7376dc37e7fad1e803995fd39f42848
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All warnings (new ones prefixed by >>):
> drivers/media/pci/intel/ipu3/ipu3-cio2.c:163:56: warning:
implicit conversion from 'unsigned long' to 'u16' (aka 'unsigned
short') changes value from 131072 to 0 [-Wconstant-conversion]
entry[1].second_entry.num_of_pages = CIO2_LOP_ENTRIES * CIO2_MAX_LOPS;
~ ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
1 warning generated.
vim +163 drivers/media/pci/intel/ipu3/ipu3-cio2.c
154
155 /* Initialize fpbt entries to point to dummy frame */
156 static void cio2_fbpt_entry_init_dummy(struct cio2_device *cio2,
157 struct cio2_fbpt_entry
158 entry[CIO2_MAX_LOPS])
159 {
160 unsigned int i;
161
162 entry[0].first_entry.first_page_offset = 0;
163 entry[1].second_entry.num_of_pages = CIO2_LOP_ENTRIES *
CIO2_MAX_LOPS;
164 entry[1].second_entry.last_page_available_bytes =
CIO2_PAGE_SIZE - 1;
165
166 for (i = 0; i < CIO2_MAX_LOPS; i++)
167 entry[i].lop_page_addr = cio2->dummy_lop_bus_addr >> PAGE_SHIFT;
168
169 cio2_fbpt_entry_enable(cio2, entry);
170 }
171
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
10:40 a.m.
On Sat, Nov 21, 2020 at 04:23:05PM +0800, kernel test robot wrote:
tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 27bba9c532a8d21050b94224ffd310ad0058c353
commit: 7b285f41f7376dc37e7fad1e803995fd39f42848 media: ipu3-cio2: Introduce
CIO2_LOP_ENTRIES constant
date: 2 months ago
config: arm64-randconfig-r031-20201121 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project
bec968cbb367dd03439c89c1d4ef968ef662d7c0)
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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit...
git remote add linus
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
git fetch --no-tags linus master
git checkout 7b285f41f7376dc37e7fad1e803995fd39f42848
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All warnings (new ones prefixed by >>):
>> drivers/media/pci/intel/ipu3/ipu3-cio2.c:163:56: warning: implicit conversion
from 'unsigned long' to 'u16' (aka 'unsigned short') changes value
from 131072 to 0 [-Wconstant-conversion]
entry[1].second_entry.num_of_pages = CIO2_LOP_ENTRIES * CIO2_MAX_LOPS;
~ ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
1 warning generated.
Okay, now we have an interesting case. The IP is quite unlikely be used on
ARM64, but my patches made the clear picture about use of PAGE_SIZE here.
So, I see at least the following options to mitigate the above, i.e.:
1/ reduce driver scope to X86
2/ fix the variables to be wider type to be able to hold PAGE_SIZE > 4k
3/ switch to custom PAGE_SIZE / _SHIFT / _MASK and accompanying macros
And I still consider 3/ is silly move because as we see the driver was
never assumed to work with big page sizes (besides unsigned short type
here, PAGE_SHIFT and PAGE_MASK in the original code was as is and on ARM64
they compiled to 0 values w/o warnings, effectively make the driver
improperly functioning anyway).
--
With Best Regards,
Andy Shevchenko
4:56 p.m.
Hi Andy,
On Mon, Nov 23, 2020 at 12:40:18PM +0200, Andy Shevchenko wrote:
On Sat, Nov 21, 2020 at 04:23:05PM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 27bba9c532a8d21050b94224ffd310ad0058c353
> commit: 7b285f41f7376dc37e7fad1e803995fd39f42848 media: ipu3-cio2: Introduce
CIO2_LOP_ENTRIES constant
> date: 2 months ago
> config: arm64-randconfig-r031-20201121 (attached as .config)
> compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project
bec968cbb367dd03439c89c1d4ef968ef662d7c0)
> 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://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit...
> git remote add linus
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout 7b285f41f7376dc37e7fad1e803995fd39f42848
> # save the attached .config to linux build tree
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp(a)intel.com>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/media/pci/intel/ipu3/ipu3-cio2.c:163:56: warning: implicit
conversion from 'unsigned long' to 'u16' (aka 'unsigned short')
changes value from 131072 to 0 [-Wconstant-conversion]
> entry[1].second_entry.num_of_pages = CIO2_LOP_ENTRIES * CIO2_MAX_LOPS;
> ~ ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
> 1 warning generated.
Okay, now we have an interesting case. The IP is quite unlikely be used on
ARM64, but my patches made the clear picture about use of PAGE_SIZE here.
So, I see at least the following options to mitigate the above, i.e.:
1/ reduce driver scope to X86
2/ fix the variables to be wider type to be able to hold PAGE_SIZE > 4k
3/ switch to custom PAGE_SIZE / _SHIFT / _MASK and accompanying macros
And I still consider 3/ is silly move because as we see the driver was
never assumed to work with big page sizes (besides unsigned short type
here, PAGE_SHIFT and PAGE_MASK in the original code was as is and on ARM64
they compiled to 0 values w/o warnings, effectively make the driver
improperly functioning anyway).
Apologies for the late answer.
I think I'd favour the first option. It's not really useful to be able to
compile this elsewhere; as such the driver doesn't do anything special that
would make it prone to breakage through changes elsewhere.
Would you like to send a patch? :-)
--
Kind regards,
Sakari Ailus
3:29 p.m.
On Fri, Dec 11, 2020 at 06:56:14PM +0200, Sakari Ailus wrote:
On Mon, Nov 23, 2020 at 12:40:18PM +0200, Andy Shevchenko wrote:
> On Sat, Nov 21, 2020 at 04:23:05PM +0800, kernel test robot wrote:
...
> > All warnings (new ones prefixed by >>):
> >
> > >> drivers/media/pci/intel/ipu3/ipu3-cio2.c:163:56: warning: implicit
conversion from 'unsigned long' to 'u16' (aka 'unsigned short')
changes value from 131072 to 0 [-Wconstant-conversion]
> > entry[1].second_entry.num_of_pages = CIO2_LOP_ENTRIES *
CIO2_MAX_LOPS;
> > ~
~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~
> > 1 warning generated.
>
> Okay, now we have an interesting case. The IP is quite unlikely be used on
> ARM64, but my patches made the clear picture about use of PAGE_SIZE here.
>
> So, I see at least the following options to mitigate the above, i.e.:
> 1/ reduce driver scope to X86
> 2/ fix the variables to be wider type to be able to hold PAGE_SIZE > 4k
> 3/ switch to custom PAGE_SIZE / _SHIFT / _MASK and accompanying macros
>
> And I still consider 3/ is silly move because as we see the driver was
> never assumed to work with big page sizes (besides unsigned short type
> here, PAGE_SHIFT and PAGE_MASK in the original code was as is and on ARM64
> they compiled to 0 values w/o warnings, effectively make the driver
> improperly functioning anyway).
Apologies for the late answer.
I think I'd favour the first option. It's not really useful to be able to
compile this elsewhere; as such the driver doesn't do anything special that
would make it prone to breakage through changes elsewhere.
Would you like to send a patch? :-)
Done.
--
With Best Regards,
Andy Shevchenko
76
days inactive
99
days old
3 comments
3 participants
participants (3)
-
Andy Shevchenko -
kernel test robot -
Sakari Ailus