linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
* [linux-next:master 5496/6100] mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next'.
@ 2023-03-24  5:03 Dan Carpenter
  2023-03-24  8:01 ` Lorenzo Stoakes
  0 siblings, 1 reply; 2+ messages in thread
From: Dan Carpenter @ 2023-03-24  5:03 UTC (permalink / raw)
  To: oe-kbuild, Lorenzo Stoakes
  Cc: lkp, oe-kbuild-all, Linux Memory Management List, Andrew Morton

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   7c4a254d78f89546d0e74a40617ef24c6151c8d1
commit: e887ecae997ebaaad4d9b93e6a01fd5495ec1bc3 [5496/6100] mm/mmap/vma_merge: set next to NULL if not applicable
config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230324/202303240246.9rvyIPWZ-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-8) 11.3.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Link: https://lore.kernel.org/r/202303240246.9rvyIPWZ-lkp@intel.com/

smatch warnings:
mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next'.

vim +/next +962 mm/mmap.c

9760ebffbf5507 Liam R. Howlett    2023-01-20   904  struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm,
^1da177e4c3f41 Linus Torvalds     2005-04-16   905  			struct vm_area_struct *prev, unsigned long addr,
^1da177e4c3f41 Linus Torvalds     2005-04-16   906  			unsigned long end, unsigned long vm_flags,
^1da177e4c3f41 Linus Torvalds     2005-04-16   907  			struct anon_vma *anon_vma, struct file *file,
19a809afe2fe08 Andrea Arcangeli   2015-09-04   908  			pgoff_t pgoff, struct mempolicy *policy,
9a10064f5625d5 Colin Cross        2022-01-14   909  			struct vm_userfaultfd_ctx vm_userfaultfd_ctx,
5c26f6ac9416b6 Suren Baghdasaryan 2022-03-04   910  			struct anon_vma_name *anon_name)
^1da177e4c3f41 Linus Torvalds     2005-04-16   911  {
^1da177e4c3f41 Linus Torvalds     2005-04-16   912  	pgoff_t pglen = (end - addr) >> PAGE_SHIFT;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   913  	pgoff_t vma_pgoff;
721076b86904d4 Lorenzo Stoakes    2023-03-21   914  	struct vm_area_struct *curr, *next, *res = NULL;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   915  	struct vm_area_struct *vma, *adjust, *remove, *remove2;
eef199440df950 Jakub Matěna       2022-06-03   916  	int err = -1;
eef199440df950 Jakub Matěna       2022-06-03   917  	bool merge_prev = false;
eef199440df950 Jakub Matěna       2022-06-03   918  	bool merge_next = false;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   919  	bool vma_expanded = false;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   920  	struct vma_prepare vp;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   921  	unsigned long vma_end = end;
27d6788ee67b59 Vlastimil Babka    2023-03-09   922  	long adj_start = 0;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   923  	unsigned long vma_start = addr;
^1da177e4c3f41 Linus Torvalds     2005-04-16   924  
0503ea8f5ba73e Liam R. Howlett    2023-01-20   925  	validate_mm(mm);
^1da177e4c3f41 Linus Torvalds     2005-04-16   926  	/*
^1da177e4c3f41 Linus Torvalds     2005-04-16   927  	 * We later require that vma->vm_flags == vm_flags,
^1da177e4c3f41 Linus Torvalds     2005-04-16   928  	 * so this tests vma->vm_flags & VM_SPECIAL, too.
^1da177e4c3f41 Linus Torvalds     2005-04-16   929  	 */
^1da177e4c3f41 Linus Torvalds     2005-04-16   930  	if (vm_flags & VM_SPECIAL)
^1da177e4c3f41 Linus Torvalds     2005-04-16   931  		return NULL;
^1da177e4c3f41 Linus Torvalds     2005-04-16   932  
e887ecae997eba Lorenzo Stoakes    2023-03-21   933  	/* Does the input range span an existing VMA? (cases 5 - 8) */
e887ecae997eba Lorenzo Stoakes    2023-03-21   934  	curr = find_vma_intersection(mm, prev ? prev->vm_end : 0, end);
^1da177e4c3f41 Linus Torvalds     2005-04-16   935  
e887ecae997eba Lorenzo Stoakes    2023-03-21   936  	if (curr && end == curr->vm_end)
e887ecae997eba Lorenzo Stoakes    2023-03-21   937  		/* Is there is a VMA immediately adjacent (cases 6 - 8)? */
e887ecae997eba Lorenzo Stoakes    2023-03-21   938  		next = vma_lookup(mm, curr->vm_end);
e887ecae997eba Lorenzo Stoakes    2023-03-21   939  	else if (!curr)
e887ecae997eba Lorenzo Stoakes    2023-03-21   940  		/* Is there a VMA next to a hole (case 1 - 3) or prev (4)? */
e887ecae997eba Lorenzo Stoakes    2023-03-21   941  		next = vma_lookup(mm, end);

next not initialized on else path.

759224a5ffcfa1 Vlastimil Babka    2023-03-09   942  
e86f15ee64d8ee Andrea Arcangeli   2016-10-07   943  	/* verify some invariant that must be enforced by the caller */
e86f15ee64d8ee Andrea Arcangeli   2016-10-07   944  	VM_WARN_ON(prev && addr <= prev->vm_start);
721076b86904d4 Lorenzo Stoakes    2023-03-21   945  	VM_WARN_ON(curr && end > curr->vm_end);
e86f15ee64d8ee Andrea Arcangeli   2016-10-07   946  	VM_WARN_ON(addr >= end);
e86f15ee64d8ee Andrea Arcangeli   2016-10-07   947  
0503ea8f5ba73e Liam R. Howlett    2023-01-20   948  	if (prev) {
0503ea8f5ba73e Liam R. Howlett    2023-01-20   949  		res = prev;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   950  		vma = prev;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   951  		vma_start = prev->vm_start;
0503ea8f5ba73e Liam R. Howlett    2023-01-20   952  		vma_pgoff = prev->vm_pgoff;
eef199440df950 Jakub Matěna       2022-06-03   953  		/* Can we merge the predecessor? */
0503ea8f5ba73e Liam R. Howlett    2023-01-20   954  		if (prev->vm_end == addr && mpol_equal(vma_policy(prev), policy)
0503ea8f5ba73e Liam R. Howlett    2023-01-20   955  		    && can_vma_merge_after(prev, vm_flags, anon_vma, file,
0503ea8f5ba73e Liam R. Howlett    2023-01-20   956  				   pgoff, vm_userfaultfd_ctx, anon_name)) {
eef199440df950 Jakub Matěna       2022-06-03   957  			merge_prev = true;
18b098af2890cd Liam R. Howlett    2023-01-20   958  			vma_prev(vmi);
eef199440df950 Jakub Matěna       2022-06-03   959  		}
0503ea8f5ba73e Liam R. Howlett    2023-01-20   960  	}
eef199440df950 Jakub Matěna       2022-06-03   961  	/* Can we merge the successor? */
e887ecae997eba Lorenzo Stoakes    2023-03-21  @962  	if (next && mpol_equal(policy, vma_policy(next)) &&
                                                            ^^^^

^1da177e4c3f41 Linus Torvalds     2005-04-16   963  	    can_vma_merge_before(next, vm_flags,
eef199440df950 Jakub Matěna       2022-06-03   964  				 anon_vma, file, pgoff+pglen,
eef199440df950 Jakub Matěna       2022-06-03   965  				 vm_userfaultfd_ctx, anon_name)) {
eef199440df950 Jakub Matěna       2022-06-03   966  		merge_next = true;
eef199440df950 Jakub Matěna       2022-06-03   967  	}
0503ea8f5ba73e Liam R. Howlett    2023-01-20   968  

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



^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [linux-next:master 5496/6100] mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next'.
  2023-03-24  5:03 [linux-next:master 5496/6100] mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next' Dan Carpenter
@ 2023-03-24  8:01 ` Lorenzo Stoakes
  0 siblings, 0 replies; 2+ messages in thread
From: Lorenzo Stoakes @ 2023-03-24  8:01 UTC (permalink / raw)
  To: Dan Carpenter
  Cc: oe-kbuild, lkp, oe-kbuild-all, Linux Memory Management List,
	Andrew Morton

On Fri, Mar 24, 2023 at 08:03:52AM +0300, Dan Carpenter wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   7c4a254d78f89546d0e74a40617ef24c6151c8d1
> commit: e887ecae997ebaaad4d9b93e6a01fd5495ec1bc3 [5496/6100] mm/mmap/vma_merge: set next to NULL if not applicable
> config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230324/202303240246.9rvyIPWZ-lkp@intel.com/config)
> compiler: gcc-11 (Debian 11.3.0-8) 11.3.0
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> | Reported-by: Dan Carpenter <error27@gmail.com>
> | Link: https://lore.kernel.org/r/202303240246.9rvyIPWZ-lkp@intel.com/
>
> smatch warnings:
> mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next'.
>

Hi, sorry for breaking -next (this is the nth report for this :) but this
is a mistake that accidentally slipped in a while ago, it was fixed in v3
of the patch series which is currently in mm-unstable and should land in
-next when mm is next integrated (no pun intended).

See https://lore.kernel.org/all/cover.1679516210.git.lstoakes@gmail.com for
the latest version of the series in question.

Thanks for the report and it's really nice to see how many people are on
top of these things!

> vim +/next +962 mm/mmap.c
>
> 9760ebffbf5507 Liam R. Howlett    2023-01-20   904  struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *mm,
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   905  			struct vm_area_struct *prev, unsigned long addr,
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   906  			unsigned long end, unsigned long vm_flags,
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   907  			struct anon_vma *anon_vma, struct file *file,
> 19a809afe2fe08 Andrea Arcangeli   2015-09-04   908  			pgoff_t pgoff, struct mempolicy *policy,
> 9a10064f5625d5 Colin Cross        2022-01-14   909  			struct vm_userfaultfd_ctx vm_userfaultfd_ctx,
> 5c26f6ac9416b6 Suren Baghdasaryan 2022-03-04   910  			struct anon_vma_name *anon_name)
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   911  {
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   912  	pgoff_t pglen = (end - addr) >> PAGE_SHIFT;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   913  	pgoff_t vma_pgoff;
> 721076b86904d4 Lorenzo Stoakes    2023-03-21   914  	struct vm_area_struct *curr, *next, *res = NULL;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   915  	struct vm_area_struct *vma, *adjust, *remove, *remove2;
> eef199440df950 Jakub Matěna       2022-06-03   916  	int err = -1;
> eef199440df950 Jakub Matěna       2022-06-03   917  	bool merge_prev = false;
> eef199440df950 Jakub Matěna       2022-06-03   918  	bool merge_next = false;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   919  	bool vma_expanded = false;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   920  	struct vma_prepare vp;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   921  	unsigned long vma_end = end;
> 27d6788ee67b59 Vlastimil Babka    2023-03-09   922  	long adj_start = 0;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   923  	unsigned long vma_start = addr;
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   924
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   925  	validate_mm(mm);
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   926  	/*
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   927  	 * We later require that vma->vm_flags == vm_flags,
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   928  	 * so this tests vma->vm_flags & VM_SPECIAL, too.
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   929  	 */
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   930  	if (vm_flags & VM_SPECIAL)
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   931  		return NULL;
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   932
> e887ecae997eba Lorenzo Stoakes    2023-03-21   933  	/* Does the input range span an existing VMA? (cases 5 - 8) */
> e887ecae997eba Lorenzo Stoakes    2023-03-21   934  	curr = find_vma_intersection(mm, prev ? prev->vm_end : 0, end);
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   935
> e887ecae997eba Lorenzo Stoakes    2023-03-21   936  	if (curr && end == curr->vm_end)
> e887ecae997eba Lorenzo Stoakes    2023-03-21   937  		/* Is there is a VMA immediately adjacent (cases 6 - 8)? */
> e887ecae997eba Lorenzo Stoakes    2023-03-21   938  		next = vma_lookup(mm, curr->vm_end);
> e887ecae997eba Lorenzo Stoakes    2023-03-21   939  	else if (!curr)
> e887ecae997eba Lorenzo Stoakes    2023-03-21   940  		/* Is there a VMA next to a hole (case 1 - 3) or prev (4)? */
> e887ecae997eba Lorenzo Stoakes    2023-03-21   941  		next = vma_lookup(mm, end);
>
> next not initialized on else path.
>
> 759224a5ffcfa1 Vlastimil Babka    2023-03-09   942
> e86f15ee64d8ee Andrea Arcangeli   2016-10-07   943  	/* verify some invariant that must be enforced by the caller */
> e86f15ee64d8ee Andrea Arcangeli   2016-10-07   944  	VM_WARN_ON(prev && addr <= prev->vm_start);
> 721076b86904d4 Lorenzo Stoakes    2023-03-21   945  	VM_WARN_ON(curr && end > curr->vm_end);
> e86f15ee64d8ee Andrea Arcangeli   2016-10-07   946  	VM_WARN_ON(addr >= end);
> e86f15ee64d8ee Andrea Arcangeli   2016-10-07   947
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   948  	if (prev) {
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   949  		res = prev;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   950  		vma = prev;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   951  		vma_start = prev->vm_start;
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   952  		vma_pgoff = prev->vm_pgoff;
> eef199440df950 Jakub Matěna       2022-06-03   953  		/* Can we merge the predecessor? */
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   954  		if (prev->vm_end == addr && mpol_equal(vma_policy(prev), policy)
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   955  		    && can_vma_merge_after(prev, vm_flags, anon_vma, file,
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   956  				   pgoff, vm_userfaultfd_ctx, anon_name)) {
> eef199440df950 Jakub Matěna       2022-06-03   957  			merge_prev = true;
> 18b098af2890cd Liam R. Howlett    2023-01-20   958  			vma_prev(vmi);
> eef199440df950 Jakub Matěna       2022-06-03   959  		}
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   960  	}
> eef199440df950 Jakub Matěna       2022-06-03   961  	/* Can we merge the successor? */
> e887ecae997eba Lorenzo Stoakes    2023-03-21  @962  	if (next && mpol_equal(policy, vma_policy(next)) &&
>                                                             ^^^^
>
> ^1da177e4c3f41 Linus Torvalds     2005-04-16   963  	    can_vma_merge_before(next, vm_flags,
> eef199440df950 Jakub Matěna       2022-06-03   964  				 anon_vma, file, pgoff+pglen,
> eef199440df950 Jakub Matěna       2022-06-03   965  				 vm_userfaultfd_ctx, anon_name)) {
> eef199440df950 Jakub Matěna       2022-06-03   966  		merge_next = true;
> eef199440df950 Jakub Matěna       2022-06-03   967  	}
> 0503ea8f5ba73e Liam R. Howlett    2023-01-20   968
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests
>


^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2023-03-24  8:01 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-03-24  5:03 [linux-next:master 5496/6100] mm/mmap.c:962 vma_merge() error: uninitialized symbol 'next' Dan Carpenter
2023-03-24  8:01 ` Lorenzo Stoakes

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox