Re: [PATCH 3/3] iommu: Enable compile testing for some of drivers

[Krzysztof Kozlowski]

On Tue, Dec 31, 2019 at 03:43:39PM +0800, kbuild test robot wrote:
> Hi Krzysztof,
> 
> I love your patch! Perhaps something to improve:
> 
> [auto build test WARNING on iommu/next]
> [also build test WARNING on v5.5-rc4]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
> 
> url:    https://github.com/0day-ci/linux/commits/Krzysztof-Kozlowski/iommu-omap-Fix-pointer-cast-Wpointer-to-int-cast-warnings-on-64-bit/20191231-022212
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu.git next
> config: ia64-allmodconfig (attached as .config)
> compiler: ia64-linux-gcc (GCC) 7.5.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         GCC_VERSION=7.5.0 make.cross ARCH=ia64 
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@xxxxxxxxx>

I saw it already while compile testing my patch. I must admit that I
could not find easy/fast fix for it.  Probably the
omap_iommu_translate() helper should be made 64-bit friendly but this
obfuscates the code. The driver and hardware supports only 32-bit addresses.

Best regards,
Krzysztof


> 
> All warnings (new ones prefixed by >>):
> 
>    In file included from drivers/iommu/omap-iommu.c:33:0:
>    drivers/iommu/omap-iommu.c: In function 'omap_iommu_iova_to_phys':
> >> drivers/iommu/omap-iopgtable.h:44:21: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>     #define IOPTE_MASK  (~(IOPTE_SIZE - 1))
>                         ^
> >> drivers/iommu/omap-iommu.c:1641:41: note: in expansion of macro 'IOPTE_MASK'
>        ret = omap_iommu_translate(*pte, da, IOPTE_MASK);
>                                             ^~~~~~~~~~
>    drivers/iommu/omap-iopgtable.h:51:23: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>     #define IOLARGE_MASK  (~(IOLARGE_SIZE - 1))
>                           ^
> >> drivers/iommu/omap-iommu.c:1643:41: note: in expansion of macro 'IOLARGE_MASK'
>        ret = omap_iommu_translate(*pte, da, IOLARGE_MASK);
>                                             ^~~~~~~~~~~~
>    drivers/iommu/omap-iopgtable.h:27:25: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>     #define IOSECTION_MASK  (~(IOSECTION_SIZE - 1))
>                             ^
> >> drivers/iommu/omap-iommu.c:1649:41: note: in expansion of macro 'IOSECTION_MASK'
>        ret = omap_iommu_translate(*pgd, da, IOSECTION_MASK);
>                                             ^~~~~~~~~~~~~~
>    drivers/iommu/omap-iopgtable.h:34:23: warning: large integer implicitly truncated to unsigned type [-Woverflow]
>     #define IOSUPER_MASK  (~(IOSUPER_SIZE - 1))
>                           ^
> >> drivers/iommu/omap-iommu.c:1651:41: note: in expansion of macro 'IOSUPER_MASK'
>        ret = omap_iommu_translate(*pgd, da, IOSUPER_MASK);
>                                             ^~~~~~~~~~~~
> 
> vim +44 drivers/iommu/omap-iopgtable.h
> 
> 97ec7d585b33bb arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2010-02-15  38  
> 97ec7d585b33bb arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2010-02-15  39  /*
> 97ec7d585b33bb arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2010-02-15  40   * "small page" address mask and size definitions.
> 97ec7d585b33bb arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2010-02-15  41   */
> a9dcad5e375800 arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2009-01-26  42  #define IOPTE_SHIFT		12
> 5ff98fa68c88d7 drivers/iommu/omap-iopgtable.h Suman Anna   2015-07-20  43  #define IOPTE_SIZE		BIT(IOPTE_SHIFT)
> a9dcad5e375800 arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2009-01-26 @44  #define IOPTE_MASK		(~(IOPTE_SIZE - 1))
> a9dcad5e375800 arch/arm/plat-omap/iopgtable.h Hiroshi DOYU 2009-01-26  45  
> 
> :::::: The code at line 44 was first introduced by commit
> :::::: a9dcad5e375800fcb07f7617dba23b3aade8f09d omap iommu: tlb and pagetable primitives
> 
> :::::: TO: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
> :::::: CC: Hiroshi DOYU <Hiroshi.DOYU@xxxxxxxxx>
> 
> ---
> 0-DAY kernel test infrastructure                 Open Source Technology Center
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