Re: [PATCH v5 2/3] RISC-V: hwprobe: Expose Zicbom extension and its block size

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

Hi Yunhui,

kernel test robot noticed the following build warnings:

[auto build test WARNING on shuah-kselftest/next]
[also build test WARNING on shuah-kselftest/fixes linus/master v6.13 next-20250121]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Yunhui-Cui/RISC-V-Enable-cbo-clean-flush-in-usermode/20250115-104456
base:   https://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest.git next
patch link:    https://lore.kernel.org/r/20250115024024.84365-3-cuiyunhui%40bytedance.com
patch subject: [PATCH v5 2/3] RISC-V: hwprobe: Expose Zicbom extension and its block size
config: riscv-randconfig-r133-20250121 (https://download.01.org/0day-ci/archive/20250121/202501212220.5GHTtuF7-lkp@intel.com/config)
compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project c23f2417dc5f6dc371afb07af5627ec2a9d373a0)
reproduce: (https://download.01.org/0day-ci/archive/20250121/202501212220.5GHTtuF7-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/202501212220.5GHTtuF7-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> arch/riscv/kernel/sys_hwprobe.c:284:30: warning: implicit conversion from 'unsigned long long' to 'unsigned long' changes value from 1125899906842624 to 0 [-Wconstant-conversion]
     284 |                 if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOM))
         |                     ~~~~~~~~~~~~~~~~       ^~~~~~~~~~~~~~~~~~~~~~~~
   arch/riscv/include/uapi/asm/hwprobe.h:76:41: note: expanded from macro 'RISCV_HWPROBE_EXT_ZICBOM'
      76 | #define         RISCV_HWPROBE_EXT_ZICBOM        (1ULL << 50)
         |                                                  ~~~~~^~~~~
   1 warning generated.


vim +284 arch/riscv/kernel/sys_hwprobe.c

   244	
   245	static void hwprobe_one_pair(struct riscv_hwprobe *pair,
   246				     const struct cpumask *cpus)
   247	{
   248		switch (pair->key) {
   249		case RISCV_HWPROBE_KEY_MVENDORID:
   250		case RISCV_HWPROBE_KEY_MARCHID:
   251		case RISCV_HWPROBE_KEY_MIMPID:
   252			hwprobe_arch_id(pair, cpus);
   253			break;
   254		/*
   255		 * The kernel already assumes that the base single-letter ISA
   256		 * extensions are supported on all harts, and only supports the
   257		 * IMA base, so just cheat a bit here and tell that to
   258		 * userspace.
   259		 */
   260		case RISCV_HWPROBE_KEY_BASE_BEHAVIOR:
   261			pair->value = RISCV_HWPROBE_BASE_BEHAVIOR_IMA;
   262			break;
   263	
   264		case RISCV_HWPROBE_KEY_IMA_EXT_0:
   265			hwprobe_isa_ext0(pair, cpus);
   266			break;
   267	
   268		case RISCV_HWPROBE_KEY_CPUPERF_0:
   269		case RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF:
   270			pair->value = hwprobe_misaligned(cpus);
   271			break;
   272	
   273		case RISCV_HWPROBE_KEY_MISALIGNED_VECTOR_PERF:
   274			pair->value = hwprobe_vec_misaligned(cpus);
   275			break;
   276	
   277		case RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE:
   278			pair->value = 0;
   279			if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOZ))
   280				pair->value = riscv_cboz_block_size;
   281			break;
   282		case RISCV_HWPROBE_KEY_ZICBOM_BLOCK_SIZE:
   283			pair->value = 0;
 > 284			if (hwprobe_ext0_has(cpus, RISCV_HWPROBE_EXT_ZICBOM))
   285				pair->value = riscv_cbom_block_size;
   286			break;
   287		case RISCV_HWPROBE_KEY_HIGHEST_VIRT_ADDRESS:
   288			pair->value = user_max_virt_addr();
   289			break;
   290	
   291		case RISCV_HWPROBE_KEY_TIME_CSR_FREQ:
   292			pair->value = riscv_timebase;
   293			break;
   294	
   295		/*
   296		 * For forward compatibility, unknown keys don't fail the whole
   297		 * call, but get their element key set to -1 and value set to 0
   298		 * indicating they're unrecognized.
   299		 */
   300		default:
   301			pair->key = -1;
   302			pair->value = 0;
   303			break;
   304		}
   305	}
   306	

-- 
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