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From: Dan Carpenter <dan.carpenter@oracle.com>
To: kbuild@lists.01.org
Subject: [rcu:willy-maple 175/202] mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.
Date: Thu, 04 Feb 2021 10:17:24 +0300	[thread overview]
Message-ID: <20210204071724.GD2696@kadam> (raw)

[-- Attachment #1: Type: text/plain, Size: 5459 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git willy-maple
head:   7e346d2845b4bd77663394f39fa70456e0084c86
commit: 3fd77bfa4f25fa2e3caec024c69168bf6a0ca8d7 [175/202] mm/ksm: Use maple tree iterators instead of vma linked list
config: x86_64-randconfig-m001-20210202 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.

vim +/mm +979 mm/ksm.c

d952b79136a6c3 Hugh Dickins      2009-09-21   965  static int unmerge_and_remove_all_rmap_items(void)
31dbd01f314364 Izik Eidus        2009-09-21   966  {
31dbd01f314364 Izik Eidus        2009-09-21   967  	struct mm_slot *mm_slot;
31dbd01f314364 Izik Eidus        2009-09-21   968  	struct mm_struct *mm;
31dbd01f314364 Izik Eidus        2009-09-21   969  	struct vm_area_struct *vma;
d952b79136a6c3 Hugh Dickins      2009-09-21   970  	int err = 0;
31dbd01f314364 Izik Eidus        2009-09-21   971  
d952b79136a6c3 Hugh Dickins      2009-09-21   972  	spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   973  	ksm_scan.mm_slot = list_entry(ksm_mm_head.mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   974  						struct mm_slot, mm_list);
d952b79136a6c3 Hugh Dickins      2009-09-21   975  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21   976  
9ba6929480088a Hugh Dickins      2009-09-21   977  	for (mm_slot = ksm_scan.mm_slot;
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   978  			mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot, mm = mm_slot->mm) {
3fd77bfa4f25fa Liam R. Howlett   2021-01-04  @979  		MA_STATE(mas, &mm->mm_mt, 0, 0);
                                                                               ^^
Not initialized on the first iteration through the loop?

3fd77bfa4f25fa Liam R. Howlett   2021-01-04   980  
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   981  		mmap_read_lock(mm);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   982  		mas_set(&mas, 0);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   983  		mas_for_each(&mas, vma, ULONG_MAX) {
9ba6929480088a Hugh Dickins      2009-09-21   984  			if (ksm_test_exit(mm))
9ba6929480088a Hugh Dickins      2009-09-21   985  				break;
31dbd01f314364 Izik Eidus        2009-09-21   986  			if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)
31dbd01f314364 Izik Eidus        2009-09-21   987  				continue;
d952b79136a6c3 Hugh Dickins      2009-09-21   988  			err = unmerge_ksm_pages(vma,
d952b79136a6c3 Hugh Dickins      2009-09-21   989  						vma->vm_start, vma->vm_end);
9ba6929480088a Hugh Dickins      2009-09-21   990  			if (err)
9ba6929480088a Hugh Dickins      2009-09-21   991  				goto error;
31dbd01f314364 Izik Eidus        2009-09-21   992  		}
9ba6929480088a Hugh Dickins      2009-09-21   993  
6514d511dbe5a7 Hugh Dickins      2009-12-14   994  		remove_trailing_rmap_items(mm_slot, &mm_slot->rmap_list);
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   995  		mmap_read_unlock(mm);
d952b79136a6c3 Hugh Dickins      2009-09-21   996  
d952b79136a6c3 Hugh Dickins      2009-09-21   997  		spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   998  		ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   999  						struct mm_slot, mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1000  		if (ksm_test_exit(mm)) {
4ca3a69bcb6875 Sasha Levin       2013-02-22  1001  			hash_del(&mm_slot->link);
9ba6929480088a Hugh Dickins      2009-09-21  1002  			list_del(&mm_slot->mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1003  			spin_unlock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21  1004  
9ba6929480088a Hugh Dickins      2009-09-21  1005  			free_mm_slot(mm_slot);
9ba6929480088a Hugh Dickins      2009-09-21  1006  			clear_bit(MMF_VM_MERGEABLE, &mm->flags);
9ba6929480088a Hugh Dickins      2009-09-21  1007  			mmdrop(mm);
7496fea9a6bf64 Zhou Chengming    2016-05-12  1008  		} else
d952b79136a6c3 Hugh Dickins      2009-09-21  1009  			spin_unlock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1010  	}
31dbd01f314364 Izik Eidus        2009-09-21  1011  
cbf86cfe04a664 Hugh Dickins      2013-02-22  1012  	/* Clean up stable nodes, but don't worry if some are still busy */
cbf86cfe04a664 Hugh Dickins      2013-02-22  1013  	remove_all_stable_nodes();
d952b79136a6c3 Hugh Dickins      2009-09-21  1014  	ksm_scan.seqnr = 0;
9ba6929480088a Hugh Dickins      2009-09-21  1015  	return 0;
9ba6929480088a Hugh Dickins      2009-09-21  1016  
9ba6929480088a Hugh Dickins      2009-09-21  1017  error:
d8ed45c5dcd455 Michel Lespinasse 2020-06-08  1018  	mmap_read_unlock(mm);
31dbd01f314364 Izik Eidus        2009-09-21  1019  	spin_lock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1020  	ksm_scan.mm_slot = &ksm_mm_head;
31dbd01f314364 Izik Eidus        2009-09-21  1021  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21  1022  	return err;
31dbd01f314364 Izik Eidus        2009-09-21  1023  }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 34023 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: kbuild-all@lists.01.org
Subject: [rcu:willy-maple 175/202] mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.
Date: Thu, 04 Feb 2021 10:17:24 +0300	[thread overview]
Message-ID: <20210204071724.GD2696@kadam> (raw)

[-- Attachment #1: Type: text/plain, Size: 5459 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git willy-maple
head:   7e346d2845b4bd77663394f39fa70456e0084c86
commit: 3fd77bfa4f25fa2e3caec024c69168bf6a0ca8d7 [175/202] mm/ksm: Use maple tree iterators instead of vma linked list
config: x86_64-randconfig-m001-20210202 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.

vim +/mm +979 mm/ksm.c

d952b79136a6c3 Hugh Dickins      2009-09-21   965  static int unmerge_and_remove_all_rmap_items(void)
31dbd01f314364 Izik Eidus        2009-09-21   966  {
31dbd01f314364 Izik Eidus        2009-09-21   967  	struct mm_slot *mm_slot;
31dbd01f314364 Izik Eidus        2009-09-21   968  	struct mm_struct *mm;
31dbd01f314364 Izik Eidus        2009-09-21   969  	struct vm_area_struct *vma;
d952b79136a6c3 Hugh Dickins      2009-09-21   970  	int err = 0;
31dbd01f314364 Izik Eidus        2009-09-21   971  
d952b79136a6c3 Hugh Dickins      2009-09-21   972  	spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   973  	ksm_scan.mm_slot = list_entry(ksm_mm_head.mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   974  						struct mm_slot, mm_list);
d952b79136a6c3 Hugh Dickins      2009-09-21   975  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21   976  
9ba6929480088a Hugh Dickins      2009-09-21   977  	for (mm_slot = ksm_scan.mm_slot;
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   978  			mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot, mm = mm_slot->mm) {
3fd77bfa4f25fa Liam R. Howlett   2021-01-04  @979  		MA_STATE(mas, &mm->mm_mt, 0, 0);
                                                                               ^^
Not initialized on the first iteration through the loop?

3fd77bfa4f25fa Liam R. Howlett   2021-01-04   980  
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   981  		mmap_read_lock(mm);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   982  		mas_set(&mas, 0);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   983  		mas_for_each(&mas, vma, ULONG_MAX) {
9ba6929480088a Hugh Dickins      2009-09-21   984  			if (ksm_test_exit(mm))
9ba6929480088a Hugh Dickins      2009-09-21   985  				break;
31dbd01f314364 Izik Eidus        2009-09-21   986  			if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)
31dbd01f314364 Izik Eidus        2009-09-21   987  				continue;
d952b79136a6c3 Hugh Dickins      2009-09-21   988  			err = unmerge_ksm_pages(vma,
d952b79136a6c3 Hugh Dickins      2009-09-21   989  						vma->vm_start, vma->vm_end);
9ba6929480088a Hugh Dickins      2009-09-21   990  			if (err)
9ba6929480088a Hugh Dickins      2009-09-21   991  				goto error;
31dbd01f314364 Izik Eidus        2009-09-21   992  		}
9ba6929480088a Hugh Dickins      2009-09-21   993  
6514d511dbe5a7 Hugh Dickins      2009-12-14   994  		remove_trailing_rmap_items(mm_slot, &mm_slot->rmap_list);
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   995  		mmap_read_unlock(mm);
d952b79136a6c3 Hugh Dickins      2009-09-21   996  
d952b79136a6c3 Hugh Dickins      2009-09-21   997  		spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   998  		ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   999  						struct mm_slot, mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1000  		if (ksm_test_exit(mm)) {
4ca3a69bcb6875 Sasha Levin       2013-02-22  1001  			hash_del(&mm_slot->link);
9ba6929480088a Hugh Dickins      2009-09-21  1002  			list_del(&mm_slot->mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1003  			spin_unlock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21  1004  
9ba6929480088a Hugh Dickins      2009-09-21  1005  			free_mm_slot(mm_slot);
9ba6929480088a Hugh Dickins      2009-09-21  1006  			clear_bit(MMF_VM_MERGEABLE, &mm->flags);
9ba6929480088a Hugh Dickins      2009-09-21  1007  			mmdrop(mm);
7496fea9a6bf64 Zhou Chengming    2016-05-12  1008  		} else
d952b79136a6c3 Hugh Dickins      2009-09-21  1009  			spin_unlock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1010  	}
31dbd01f314364 Izik Eidus        2009-09-21  1011  
cbf86cfe04a664 Hugh Dickins      2013-02-22  1012  	/* Clean up stable nodes, but don't worry if some are still busy */
cbf86cfe04a664 Hugh Dickins      2013-02-22  1013  	remove_all_stable_nodes();
d952b79136a6c3 Hugh Dickins      2009-09-21  1014  	ksm_scan.seqnr = 0;
9ba6929480088a Hugh Dickins      2009-09-21  1015  	return 0;
9ba6929480088a Hugh Dickins      2009-09-21  1016  
9ba6929480088a Hugh Dickins      2009-09-21  1017  error:
d8ed45c5dcd455 Michel Lespinasse 2020-06-08  1018  	mmap_read_unlock(mm);
31dbd01f314364 Izik Eidus        2009-09-21  1019  	spin_lock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1020  	ksm_scan.mm_slot = &ksm_mm_head;
31dbd01f314364 Izik Eidus        2009-09-21  1021  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21  1022  	return err;
31dbd01f314364 Izik Eidus        2009-09-21  1023  }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 34023 bytes --]

WARNING: multiple messages have this Message-ID (diff)
From: Dan Carpenter <dan.carpenter@oracle.com>
To: kbuild@lists.01.org, "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: lkp@intel.com, kbuild-all@lists.01.org, linux-kernel@vger.kernel.org
Subject: [rcu:willy-maple 175/202] mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.
Date: Thu, 4 Feb 2021 10:17:24 +0300	[thread overview]
Message-ID: <20210204071724.GD2696@kadam> (raw)

[-- Attachment #1: Type: text/plain, Size: 5376 bytes --]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git willy-maple
head:   7e346d2845b4bd77663394f39fa70456e0084c86
commit: 3fd77bfa4f25fa2e3caec024c69168bf6a0ca8d7 [175/202] mm/ksm: Use maple tree iterators instead of vma linked list
config: x86_64-randconfig-m001-20210202 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

smatch warnings:
mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm'.

vim +/mm +979 mm/ksm.c

d952b79136a6c3 Hugh Dickins      2009-09-21   965  static int unmerge_and_remove_all_rmap_items(void)
31dbd01f314364 Izik Eidus        2009-09-21   966  {
31dbd01f314364 Izik Eidus        2009-09-21   967  	struct mm_slot *mm_slot;
31dbd01f314364 Izik Eidus        2009-09-21   968  	struct mm_struct *mm;
31dbd01f314364 Izik Eidus        2009-09-21   969  	struct vm_area_struct *vma;
d952b79136a6c3 Hugh Dickins      2009-09-21   970  	int err = 0;
31dbd01f314364 Izik Eidus        2009-09-21   971  
d952b79136a6c3 Hugh Dickins      2009-09-21   972  	spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   973  	ksm_scan.mm_slot = list_entry(ksm_mm_head.mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   974  						struct mm_slot, mm_list);
d952b79136a6c3 Hugh Dickins      2009-09-21   975  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21   976  
9ba6929480088a Hugh Dickins      2009-09-21   977  	for (mm_slot = ksm_scan.mm_slot;
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   978  			mm_slot != &ksm_mm_head; mm_slot = ksm_scan.mm_slot, mm = mm_slot->mm) {
3fd77bfa4f25fa Liam R. Howlett   2021-01-04  @979  		MA_STATE(mas, &mm->mm_mt, 0, 0);
                                                                               ^^
Not initialized on the first iteration through the loop?

3fd77bfa4f25fa Liam R. Howlett   2021-01-04   980  
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   981  		mmap_read_lock(mm);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   982  		mas_set(&mas, 0);
3fd77bfa4f25fa Liam R. Howlett   2021-01-04   983  		mas_for_each(&mas, vma, ULONG_MAX) {
9ba6929480088a Hugh Dickins      2009-09-21   984  			if (ksm_test_exit(mm))
9ba6929480088a Hugh Dickins      2009-09-21   985  				break;
31dbd01f314364 Izik Eidus        2009-09-21   986  			if (!(vma->vm_flags & VM_MERGEABLE) || !vma->anon_vma)
31dbd01f314364 Izik Eidus        2009-09-21   987  				continue;
d952b79136a6c3 Hugh Dickins      2009-09-21   988  			err = unmerge_ksm_pages(vma,
d952b79136a6c3 Hugh Dickins      2009-09-21   989  						vma->vm_start, vma->vm_end);
9ba6929480088a Hugh Dickins      2009-09-21   990  			if (err)
9ba6929480088a Hugh Dickins      2009-09-21   991  				goto error;
31dbd01f314364 Izik Eidus        2009-09-21   992  		}
9ba6929480088a Hugh Dickins      2009-09-21   993  
6514d511dbe5a7 Hugh Dickins      2009-12-14   994  		remove_trailing_rmap_items(mm_slot, &mm_slot->rmap_list);
d8ed45c5dcd455 Michel Lespinasse 2020-06-08   995  		mmap_read_unlock(mm);
d952b79136a6c3 Hugh Dickins      2009-09-21   996  
d952b79136a6c3 Hugh Dickins      2009-09-21   997  		spin_lock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21   998  		ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next,
d952b79136a6c3 Hugh Dickins      2009-09-21   999  						struct mm_slot, mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1000  		if (ksm_test_exit(mm)) {
4ca3a69bcb6875 Sasha Levin       2013-02-22  1001  			hash_del(&mm_slot->link);
9ba6929480088a Hugh Dickins      2009-09-21  1002  			list_del(&mm_slot->mm_list);
9ba6929480088a Hugh Dickins      2009-09-21  1003  			spin_unlock(&ksm_mmlist_lock);
9ba6929480088a Hugh Dickins      2009-09-21  1004  
9ba6929480088a Hugh Dickins      2009-09-21  1005  			free_mm_slot(mm_slot);
9ba6929480088a Hugh Dickins      2009-09-21  1006  			clear_bit(MMF_VM_MERGEABLE, &mm->flags);
9ba6929480088a Hugh Dickins      2009-09-21  1007  			mmdrop(mm);
7496fea9a6bf64 Zhou Chengming    2016-05-12  1008  		} else
d952b79136a6c3 Hugh Dickins      2009-09-21  1009  			spin_unlock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1010  	}
31dbd01f314364 Izik Eidus        2009-09-21  1011  
cbf86cfe04a664 Hugh Dickins      2013-02-22  1012  	/* Clean up stable nodes, but don't worry if some are still busy */
cbf86cfe04a664 Hugh Dickins      2013-02-22  1013  	remove_all_stable_nodes();
d952b79136a6c3 Hugh Dickins      2009-09-21  1014  	ksm_scan.seqnr = 0;
9ba6929480088a Hugh Dickins      2009-09-21  1015  	return 0;
9ba6929480088a Hugh Dickins      2009-09-21  1016  
9ba6929480088a Hugh Dickins      2009-09-21  1017  error:
d8ed45c5dcd455 Michel Lespinasse 2020-06-08  1018  	mmap_read_unlock(mm);
31dbd01f314364 Izik Eidus        2009-09-21  1019  	spin_lock(&ksm_mmlist_lock);
31dbd01f314364 Izik Eidus        2009-09-21  1020  	ksm_scan.mm_slot = &ksm_mm_head;
31dbd01f314364 Izik Eidus        2009-09-21  1021  	spin_unlock(&ksm_mmlist_lock);
d952b79136a6c3 Hugh Dickins      2009-09-21  1022  	return err;
31dbd01f314364 Izik Eidus        2009-09-21  1023  }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 34023 bytes --]

             reply	other threads:[~2021-02-04  7:17 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-04  7:17 Dan Carpenter [this message]
2021-02-04  7:17 ` [rcu:willy-maple 175/202] mm/ksm.c:979 unmerge_and_remove_all_rmap_items() error: uninitialized symbol 'mm' Dan Carpenter
2021-02-04  7:17 ` Dan Carpenter
  -- strict thread matches above, loose matches on Subject: below --
2021-02-04  6:05 kernel test robot

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