kernel/futex/core.c:62:16: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

kernel/futex/core.c:62:16: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

[kernel test robot]

:::::: 
:::::: Manual check reason: "bisect to a FBC not belonging to original linux-review patches: branch: linux-review/UPDATE-20260702-004403/K-Prateek-Nayak/x86-runtime-const-Introduce-runtime_const_mask_32/20260630-130124, commit: b6e8471b174f2264b132157c6a5b58fd8935e1c9"
:::::: 

BCC: lkp@intel.com
CC: oe-kbuild-all@lists.linux.dev
TO: Peter Zijlstra <peterz@infradead.org>
CC: 0day robot <lkp@intel.com>
CC: K Prateek Nayak <kprateek.nayak@amd.com>

Hi Peter,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree:   https://github.com/intel-lab-lkp/linux/commits/UPDATE-20260702-004403/K-Prateek-Nayak/x86-runtime-const-Introduce-runtime_const_mask_32/20260630-130124
head:   c5019a5edc81040af1fdd5cb6685672b7d09cf6e
commit: b6e8471b174f2264b132157c6a5b58fd8935e1c9 futex: Use runtime constants for __futex_hash() hot path
date:   14 hours ago
:::::: branch date: 14 hours ago
:::::: commit date: 14 hours ago
config: i386-randconfig-r112-20260702 (https://download.01.org/0day-ci/archive/20260702/202607021439.koGQ9S5r-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260702/202607021439.koGQ9S5r-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/r/202607021439.koGQ9S5r-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   kernel/futex/core.c:532:38: sparse: sparse: cast removes address space '__user' of expression
   kernel/futex/core.c:532:51: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected unsigned int [noderef] [usertype] __user *naddr @@     got void * @@
   kernel/futex/core.c:532:51: sparse:     expected unsigned int [noderef] [usertype] __user *naddr
   kernel/futex/core.c:532:51: sparse:     got void *
   kernel/futex/core.c:548:38: sparse: sparse: cast removes address space '__user' of expression
   kernel/futex/core.c:548:51: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected unsigned int [noderef] [usertype] __user *naddr @@     got void * @@
   kernel/futex/core.c:548:51: sparse:     expected unsigned int [noderef] [usertype] __user *naddr
   kernel/futex/core.c:548:51: sparse:     got void *
>> kernel/futex/core.c:62:16: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

vim +62 kernel/futex/core.c

cec199c5e39bde7 kernel/futex/core.c Peter Zijlstra  2025-04-16  59  
b6e8471b174f226 kernel/futex/core.c Peter Zijlstra  2026-06-30  60  static __always_inline struct futex_hash_bucket **futex_queues(void)
b6e8471b174f226 kernel/futex/core.c Peter Zijlstra  2026-06-30  61  {
b6e8471b174f226 kernel/futex/core.c Peter Zijlstra  2026-06-30 @62  	return runtime_const_ptr(__futex_queues);
b6e8471b174f226 kernel/futex/core.c Peter Zijlstra  2026-06-30  63  }
a52b89ebb6d4499 kernel/futex.c      Davidlohr Bueso 2014-01-12  64  

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kernel/futex/core.c:62:16: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

[kernel test robot]

Hi Peter,

FYI, the error/warning was bisected to this commit, please ignore it if it's irrelevant.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   08df884136f1c1197bab2a27814404fd329d9aac
commit: b78b0b65825275f58336a43611a700de174be8c3 futex: Use runtime constants for __futex_hash() hot path
date:   6 weeks ago
config: i386-randconfig-063-20260911 (https://download.01.org/0day-ci/archive/20260911/202609110834.wO7fAXlN-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260911/202609110834.wO7fAXlN-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
| Fixes: b78b0b658252 ("futex: Use runtime constants for __futex_hash() hot path")
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202609110834.wO7fAXlN-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   kernel/futex/core.c:532:38: sparse: sparse: cast removes address space '__user' of expression
   kernel/futex/core.c:532:51: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected unsigned int [noderef] [usertype] __user *naddr @@     got void * @@
   kernel/futex/core.c:532:51: sparse:     expected unsigned int [noderef] [usertype] __user *naddr
   kernel/futex/core.c:532:51: sparse:     got void *
   kernel/futex/core.c:548:38: sparse: sparse: cast removes address space '__user' of expression
   kernel/futex/core.c:548:51: sparse: sparse: incorrect type in initializer (different address spaces) @@     expected unsigned int [noderef] [usertype] __user *naddr @@     got void * @@
   kernel/futex/core.c:548:51: sparse:     expected unsigned int [noderef] [usertype] __user *naddr
   kernel/futex/core.c:548:51: sparse:     got void *
>> kernel/futex/core.c:62:16: sparse: sparse: cast truncates bits from constant value (123456789abcdef becomes 89abcdef)

vim +62 kernel/futex/core.c

    59	
    60	static __always_inline struct futex_hash_bucket **futex_queues(void)
    61	{
  > 62		return runtime_const_ptr(__futex_queues);
    63	}
    64	

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