drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgm200.c:32:9: sparse: sparse: cast truncates bits from constant value (100000000 becomes 0)

From: kernel test robot

Date: Sat Dec 13 2025 - 18:35:29 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head: 4a298a43f5e339f48d2dda0665c02b88ee9a4e03
commit: b8c9c3b822fe8e033b9802516f6466099d915488 um: stop using PCI port I/O
date: 7 months ago
config: um-randconfig-r121-20251213 (https://download.01.org/0day-ci/archive/20251214/202512140713.HUSp33rF-lkp@xxxxxxxxx/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251214/202512140713.HUSp33rF-lkp@xxxxxxxxx/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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202512140713.HUSp33rF-lkp@xxxxxxxxx/

sparse warnings: (new ones prefixed by >>)
>> drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgm200.c:32:9: sparse: sparse: cast truncates bits from constant value (100000000 becomes 0)
drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgm200.c:57:9: sparse: sparse: cast truncates bits from constant value (800000000 becomes 0)

vim +32 drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgm200.c

5f300fed645597 Ben Skeggs 2017-11-01 26
e12cf6ad43888c Ben Skeggs 2017-11-01 27 static void
e12cf6ad43888c Ben Skeggs 2017-11-01 28 gm200_vmm_pgt_sparse(struct nvkm_vmm *vmm,
e12cf6ad43888c Ben Skeggs 2017-11-01 29 struct nvkm_mmu_pt *pt, u32 ptei, u32 ptes)
e12cf6ad43888c Ben Skeggs 2017-11-01 30 {
e12cf6ad43888c Ben Skeggs 2017-11-01 31 /* VALID_FALSE + VOL tells the MMU to treat the PTE as sparse. */
e12cf6ad43888c Ben Skeggs 2017-11-01 @32 VMM_FO064(pt, vmm, ptei * 8, BIT_ULL(32) /* VOL. */, ptes);
e12cf6ad43888c Ben Skeggs 2017-11-01 33 }
e12cf6ad43888c Ben Skeggs 2017-11-01 34

:::::: The code at line 32 was first introduced by commit
:::::: e12cf6ad43888c152c3b2edb59525587cd98a227 drm/nouveau/mmu/gm200,gm20b: implement new vmm backend

:::::: TO: Ben Skeggs <bskeggs@xxxxxxxxxx>
:::::: CC: Ben Skeggs <bskeggs@xxxxxxxxxx>

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