[linux-next:master 11391/11746] drivers/gpu/drm/nouveau/nvkm/subdev/fb/gf100.c:84:37: warning: result of comparison of constant 1099511627775 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false

[linux-next:master 11391/11746] drivers/gpu/drm/nouveau/nvkm/subdev/fb/gf100.c:84:37: warning: result of comparison of constant 1099511627775 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   92fd6e84175befa1775e5c0ab682938eca27c0b2
commit: 31d3354f42c0da34415164a1f621a195caa1f1bc [11391/11746] drm/nouveau: verify that hardware supports the flush page address
config: i386-buildonly-randconfig-002-20251125 (https://download.01.org/0day-ci/archive/20251125/202511252350.7SSB6nMU-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251125/202511252350.7SSB6nMU-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/202511252350.7SSB6nMU-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/nouveau/nvkm/subdev/fb/gf100.c:84:37: warning: result of comparison of constant 1099511627775 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]
      84 |         WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(40));
         |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
   include/asm-generic/bug.h:123:25: note: expanded from macro 'WARN_ON'
     123 |         int __ret_warn_on = !!(condition);                              \
         |                                ^~~~~~~~~
   1 warning generated.
--
>> drivers/gpu/drm/nouveau/nvkm/subdev/fb/gb100.c:19:37: warning: result of comparison of constant 4503599627370495 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]
      19 |         WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(52));
         |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
   include/asm-generic/bug.h:123:25: note: expanded from macro 'WARN_ON'
     123 |         int __ret_warn_on = !!(condition);                              \
         |                                ^~~~~~~~~
   1 warning generated.
--
>> drivers/gpu/drm/nouveau/nvkm/subdev/fb/gh100.c:17:37: warning: result of comparison of constant 4503599627370495 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]
      17 |         WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(52));
         |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
   include/asm-generic/bug.h:123:25: note: expanded from macro 'WARN_ON'
     123 |         int __ret_warn_on = !!(condition);                              \
         |                                ^~~~~~~~~
   1 warning generated.
--
>> drivers/gpu/drm/nouveau/nvkm/subdev/fb/nv50.c:218:37: warning: result of comparison of constant 1099511627775 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]
     218 |         WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(40));
         |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
   include/asm-generic/bug.h:123:25: note: expanded from macro 'WARN_ON'
     123 |         int __ret_warn_on = !!(condition);                              \
         |                                ^~~~~~~~~
   1 warning generated.
--
>> drivers/gpu/drm/nouveau/nvkm/subdev/fb/gb202.c:17:37: warning: result of comparison of constant 4503599627370495 with expression of type 'dma_addr_t' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare]
      17 |         WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(52));
         |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~
   include/asm-generic/bug.h:123:25: note: expanded from macro 'WARN_ON'
     123 |         int __ret_warn_on = !!(condition);                              \
         |                                ^~~~~~~~~
   1 warning generated.


vim +84 drivers/gpu/drm/nouveau/nvkm/subdev/fb/gf100.c

    79	
    80	void
    81	gf100_fb_sysmem_flush_page_init(struct nvkm_fb *fb)
    82	{
    83		// Ensure that the address can actually fit in the register
  > 84		WARN_ON(fb->sysmem.flush_page_addr > DMA_BIT_MASK(40));
    85	
    86		nvkm_wr32(fb->subdev.device, 0x100c10, fb->sysmem.flush_page_addr >> 8);
    87	}
    88	

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