fs/proc/vmcore.c:458:42: warning: unused variable 'vmcore_mmap_ops'

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   c1e939a21eb111a6d6067b38e8e04b8809b64c4e
commit: c41bd2514184d75db087fe4c1221237fb7922875 kexec: drop dependency on ARCH_SUPPORTS_KEXEC from CRASH_DUMP
date:   11 months ago
config: riscv-randconfig-r054-20241030 (https://download.01.org/0day-ci/archive/20241030/202410301936.GcE8yUos-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 639a7ac648f1e50ccd2556e17d401c04f9cce625)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241030/202410301936.GcE8yUos-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410301936.GcE8yUos-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     584 |         __raw_writeb(value, PCI_IOBASE + addr);
         |                             ~~~~~~~~~~ ^
   include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     594 |         __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
   include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     604 |         __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
         |                                                       ~~~~~~~~~~ ^
   include/asm-generic/io.h:743:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     743 |         insb(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:104:53: note: expanded from macro 'insb'
     104 | #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count)
         |                                          ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:751:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     751 |         insw(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:105:53: note: expanded from macro 'insw'
     105 | #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count)
         |                                          ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:759:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     759 |         insl(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:106:53: note: expanded from macro 'insl'
     106 | #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
         |                                          ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:768:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     768 |         outsb(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:118:55: note: expanded from macro 'outsb'
     118 | #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count)
         |                                            ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:777:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     777 |         outsw(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:119:55: note: expanded from macro 'outsw'
     119 | #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count)
         |                                            ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:786:2: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
     786 |         outsl(addr, buffer, count);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/asm/io.h:120:55: note: expanded from macro 'outsl'
     120 | #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
         |                                            ~~~~~~~~~~ ^
   In file included from fs/proc/vmcore.c:18:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/riscv/include/generated/asm/hardirq.h:1:
   In file included from include/asm-generic/hardirq.h:17:
   In file included from include/linux/irq.h:20:
   In file included from include/linux/io.h:13:
   In file included from arch/riscv/include/asm/io.h:136:
   include/asm-generic/io.h:1115:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
    1115 |         return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
         |                                                   ~~~~~~~~~~ ^
>> fs/proc/vmcore.c:458:42: warning: unused variable 'vmcore_mmap_ops' [-Wunused-const-variable]
     458 | static const struct vm_operations_struct vmcore_mmap_ops = {
         |                                          ^~~~~~~~~~~~~~~
   15 warnings generated.


vim +/vmcore_mmap_ops +458 fs/proc/vmcore.c

9cb218131de1c5 Michael Holzheu 2013-09-11  457  
9cb218131de1c5 Michael Holzheu 2013-09-11 @458  static const struct vm_operations_struct vmcore_mmap_ops = {
9cb218131de1c5 Michael Holzheu 2013-09-11  459  	.fault = mmap_vmcore_fault,
9cb218131de1c5 Michael Holzheu 2013-09-11  460  };
9cb218131de1c5 Michael Holzheu 2013-09-11  461  

:::::: The code at line 458 was first introduced by commit
:::::: 9cb218131de1c59dca9063b2efe876f053f316af vmcore: introduce remap_oldmem_pfn_range()

:::::: TO: Michael Holzheu <holzheu@linux.vnet.ibm.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>

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