include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   0d839570765118029aa8bf4a95444c6a11aacf85
commit: b777b5e09eabeefc6ba80f4296366a4742701103 time/jiffies: Inline jiffies_to_msecs() and jiffies_to_usecs()
date:   6 months ago
config: alpha-randconfig-r111-20260806 (https://download.01.org/0day-ci/archive/20260806/[email protected]/config)
compiler: alpha-linux-gcc (GCC) 8.5.0
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260806/[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: b777b5e09eab ("time/jiffies: Inline jiffies_to_msecs() and jiffies_to_usecs()")
| Reported-by: kernel test robot <[email protected]>
| Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

sparse warnings: (new ones prefixed by >>)
   net/mac80211/agg-rx.c: note: in included file (through include/linux/ktime.h, include/linux/timer.h, include/linux/uprobes.h, include/linux/mm_types.h, ...):
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
--
   net/mac80211/agg-tx.c: note: in included file (through include/linux/ktime.h, include/linux/timer.h, include/linux/uprobes.h, include/linux/mm_types.h, ...):
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
--
   net/mac80211/mesh_hwmp.c: note: in included file (through include/linux/ktime.h, include/linux/timer.h, include/linux/uprobes.h, include/linux/mm_types.h, ...):
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
--
   net/mac80211/mesh.c: note: in included file (through include/linux/ktime.h, include/linux/timer.h, include/linux/uprobes.h, include/linux/mm_types.h, ...):
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
--
   net/mac80211/rx.c: note: in included file:
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
--
   net/mac80211/mlme.c: note: in included file (through include/linux/delay.h):
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)
>> include/linux/jiffies.h:470:36: sparse: sparse: cast truncates bits from constant value (3fffffffffff85ee becomes ffff85ee)

vim +470 include/linux/jiffies.h

   454	
   455	#if !(USEC_PER_SEC % HZ)
   456	/**
   457	 * jiffies_to_usecs - Convert jiffies to microseconds
   458	 * @j: jiffies value
   459	 *
   460	 * Return: microseconds value
   461	 */
   462	static inline unsigned int jiffies_to_usecs(const unsigned long j)
   463	{
   464		/*
   465		 * Hz usually doesn't go much further MSEC_PER_SEC.
   466		 * jiffies_to_usecs() and usecs_to_jiffies() depend on that.
   467		 */
   468		BUILD_BUG_ON(HZ > USEC_PER_SEC);
   469	
 > 470		return (USEC_PER_SEC / HZ) * j;
   471	}
   472	#else
   473	unsigned int jiffies_to_usecs(const unsigned long j);
   474	#endif
   475	

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