Subject: linux-next: build warning after merge of the clockevents tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 14 Aug 2025 11:16:57 +1000

Hi all,

After merging the clockevents tree, today's linux-next build (arm
multi_v7_defconfig) produced this warning:

In file included from include/linux/bitops.h:6,
                 from include/linux/log2.h:12,
                 from include/asm-generic/div64.h:55,
                 from arch/arm/include/asm/div64.h:114,
                 from include/linux/math.h:6,
                 from include/linux/math64.h:6,
                 from include/linux/time.h:6,
                 from include/uapi/linux/timex.h:56,
                 from include/linux/timex.h:56,
                 from include/linux/clocksource.h:13,
                 from include/linux/clockchips.h:14,
                 from drivers/clocksource/arm_arch_timer_mmio.c:13:
drivers/clocksource/arm_arch_timer_mmio.c: In function 'arch_timer_mmio_setup':
include/linux/bits.h:47:9: warning: conversion from 'long long unsigned int' to 'long unsigned int' changes value from '72057594037927935' to '4294967295' [-Woverflow]
   47 |         ((t)(GENMASK_INPUT_CHECK(h, l) +                        \
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   48 |              (type_max(t) << (l) &                              \
      |              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   49 |               type_max(t) >> (BITS_PER_TYPE(t) - 1 - (h)))))
      |               ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/bits.h:52:33: note: in expansion of macro 'GENMASK_TYPE'
   52 | #define GENMASK_ULL(h, l)       GENMASK_TYPE(unsigned long long, h, l)
      |                                 ^~~~~~~~~~~~
include/linux/clocksource.h:153:32: note: in expansion of macro 'GENMASK_ULL'
  153 | #define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0)
      |                                ^~~~~~~~~~~
drivers/clocksource/arm_arch_timer_mmio.c:264:66: note: in expansion of macro 'CLOCKSOURCE_MASK'
  264 |         clockevents_config_and_register(&at->evt, at->rate, 0xf, CLOCKSOURCE_MASK(56));
      |                                                                  ^~~~~~~~~~~~~~~~

Introduced by commit

  fbdd82d7f782 ("clocksource/drivers/arm_arch_timer: Add standalone MMIO driver")

-- 
Cheers,
Stephen Rothwell