Hi Andrii,

kernel test robot noticed the following build errors:

[auto build test ERROR on tip/perf/core]

url:    
https://github.com/intel-lab-lkp/linux/commits/Andrii-Nakryiko/mm-introduce-mmap_lock_speculation_-start-end/20241002-065354
base:   tip/perf/core
patch link:    
https://lore.kernel.org/r/20241001225207.2215639-6-andrii%40kernel.org
patch subject: [PATCH v2 tip/perf/core 5/5] uprobes: add speculative lockless 
VMA-to-inode-to-uprobe resolution
config: i386-defconfig 
(https://download.01.org/0day-ci/archive/20241005/[email protected]/config)
compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 
3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
reproduce (this is a W=1 build): 
(https://download.01.org/0day-ci/archive/20241005/[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
| Reported-by: kernel test robot <[email protected]>
| Closes: 
https://lore.kernel.org/oe-kbuild-all/[email protected]/

All errors (new ones prefixed by >>):

>> kernel/events/uprobes.c:2098:39: error: incompatible pointer types passing 
>> 'long *' to parameter of type 'int *' [-Werror,-Wincompatible-pointer-types]
    2098 |         if (!mmap_lock_speculation_start(mm, &seq))
         |                                              ^~~~
   include/linux/mmap_lock.h:126:75: note: passing argument to parameter 'seq' 
here
     126 | static inline bool mmap_lock_speculation_start(struct mm_struct *mm, 
int *seq) { return false; }
         |                                                                      
     ^
   1 error generated.


vim +2098 kernel/events/uprobes.c

  2086  
  2087  static struct uprobe *find_active_uprobe_speculative(unsigned long 
bp_vaddr)
  2088  {
  2089          struct mm_struct *mm = current->mm;
  2090          struct uprobe *uprobe = NULL;
  2091          struct vm_area_struct *vma;
  2092          struct file *vm_file;
  2093          loff_t offset;
  2094          long seq;
  2095  
  2096          guard(rcu)();
  2097  
> 2098          if (!mmap_lock_speculation_start(mm, &seq))
  2099                  return NULL;
  2100  
  2101          vma = vma_lookup(mm, bp_vaddr);
  2102          if (!vma)
  2103                  return NULL;
  2104  
  2105          /* vm_file memory can be reused for another instance of struct 
file,
  2106           * but can't be freed from under us, so it's safe to read 
fields from
  2107           * it, even if the values are some garbage values; ultimately
  2108           * find_uprobe_rcu() + mmap_lock_speculation_end() check will 
ensure
  2109           * that whatever we speculatively found is correct
  2110           */
  2111          vm_file = READ_ONCE(vma->vm_file);
  2112          if (!vm_file)
  2113                  return NULL;
  2114  
  2115          offset = (loff_t)(vma->vm_pgoff << PAGE_SHIFT) + (bp_vaddr - 
vma->vm_start);
  2116          uprobe = find_uprobe_rcu(vm_file->f_inode, offset);
  2117          if (!uprobe)
  2118                  return NULL;
  2119  
  2120          /* now double check that nothing about MM changed */
  2121          if (!mmap_lock_speculation_end(mm, seq))
  2122                  return NULL;
  2123  
  2124          return uprobe;
  2125  }
  2126  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

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