fs/file_table.c:241:13: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   58717b2a1365d06c8c64b72aa948541b53fe31eb
commit: 1f1651d6dc2ac282d07043358824273c15a1cac4 fs: hide file and bfile caches behind runtime const machinery
date:   4 months ago
config: i386-randconfig-061-20260716 (https://download.01.org/0day-ci/archive/20260716/[email protected]/config)
compiler: clang version 22.1.3 (https://github.com/llvm/llvm-project e9846648fd6183ee6d8cbdb4502213fcf902a211)
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260716/[email protected]/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
| Fixes: 1f1651d6dc2a ("fs: hide file and bfile caches behind runtime const machinery")
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

sparse warnings: (new ones prefixed by >>)
>> fs/file_table.c:241:13: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
>> fs/file_table.c:241:13: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:247:33: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:275:13: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:275:13: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:281:33: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:302:14: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:302:14: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:308:33: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:81:33: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)
   fs/file_table.c:83:33: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

vim +241 fs/file_table.c

   211	
   212	/* Find an unused file structure and return a pointer to it.
   213	 * Returns an error pointer if some error happend e.g. we over file
   214	 * structures limit, run out of memory or operation is not permitted.
   215	 *
   216	 * Be very careful using this.  You are responsible for
   217	 * getting write access to any mount that you might assign
   218	 * to this filp, if it is opened for write.  If this is not
   219	 * done, you will imbalance int the mount's writer count
   220	 * and a warning at __fput() time.
   221	 */
   222	struct file *alloc_empty_file(int flags, const struct cred *cred)
   223	{
   224		static long old_max;
   225		struct file *f;
   226		int error;
   227	
   228		/*
   229		 * Privileged users can go above max_files
   230		 */
   231		if (unlikely(get_nr_files() >= files_stat.max_files) &&
   232		    !capable(CAP_SYS_ADMIN)) {
   233			/*
   234			 * percpu_counters are inaccurate.  Do an expensive check before
   235			 * we go and fail.
   236			 */
   237			if (percpu_counter_sum_positive(&nr_files) >= files_stat.max_files)
   238				goto over;
   239		}
   240	
 > 241		f = kmem_cache_alloc(filp_cache, GFP_KERNEL);
   242		if (unlikely(!f))
   243			return ERR_PTR(-ENOMEM);
   244	
   245		error = init_file(f, flags, cred);
   246		if (unlikely(error)) {
   247			kmem_cache_free(filp_cache, f);
   248			return ERR_PTR(error);
   249		}
   250	
   251		percpu_counter_inc(&nr_files);
   252	
   253		return f;
   254	
   255	over:
   256		/* Ran out of filps - report that */
   257		if (get_nr_files() > old_max) {
   258			pr_info("VFS: file-max limit %lu reached\n", get_max_files());
   259			old_max = get_nr_files();
   260		}
   261		return ERR_PTR(-ENFILE);
   262	}
   263	

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