diff mbox series

[v7,13/17] mm/debug: print vm_refcnt state when dumping the vma

Message ID 20241226170710.1159679-14-surenb@google.com (mailing list archive)
State New
Headers show
Series move per-vma lock into vm_area_struct | expand

Commit Message

Suren Baghdasaryan Dec. 26, 2024, 5:07 p.m. UTC 
vm_refcnt encodes a number of useful states:
- whether vma is attached or detached
- the number of current vma readers
- presence of a vma writer
Let's include it in the vma dump.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 mm/debug.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

kernel test robot Dec. 26, 2024, 7:40 p.m. UTC | #1 
Hi Suren,

kernel test robot noticed the following build errors:

[auto build test ERROR on 431614f1580a03c1a653340c55ea76bd12a9403f]

url:    https://github.com/intel-lab-lkp/linux/commits/Suren-Baghdasaryan/mm-introduce-vma_start_read_locked-_nested-helpers/20241227-010925
base:   431614f1580a03c1a653340c55ea76bd12a9403f
patch link:    https://lore.kernel.org/r/20241226170710.1159679-14-surenb%40google.com
patch subject: [PATCH v7 13/17] mm/debug: print vm_refcnt state when dumping the vma
config: hexagon-randconfig-002-20241227 (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-lkp@intel.com/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-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/oe-kbuild-all/202412270328.HiJX1mRt-lkp@intel.com/

All errors (new ones prefixed by >>):

>> mm/debug.c:189:54: error: no member named 'vm_refcnt' in 'struct vm_area_struct'
     189 |                 vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
         |                                                               ~~~  ^
   include/linux/printk.h:514:35: note: expanded from macro 'pr_emerg'
     514 |         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
         |                                          ^~~~~~~~~~~
   include/linux/printk.h:501:60: note: expanded from macro 'printk'
     501 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
         |                                                            ^~~~~~~~~~~
   include/linux/printk.h:473:19: note: expanded from macro 'printk_index_wrap'
     473 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
         |                                 ^~~~~~~~~~~
   1 error generated.


vim +189 mm/debug.c

   178	
   179	void dump_vma(const struct vm_area_struct *vma)
   180	{
   181		pr_emerg("vma %px start %px end %px mm %px\n"
   182			"prot %lx anon_vma %px vm_ops %px\n"
   183			"pgoff %lx file %px private_data %px\n"
   184			"flags: %#lx(%pGv) refcnt %x\n",
   185			vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
   186			(unsigned long)pgprot_val(vma->vm_page_prot),
   187			vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
   188			vma->vm_file, vma->vm_private_data,
 > 189			vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
   190	}
   191	EXPORT_SYMBOL(dump_vma);
   192
Suren Baghdasaryan Dec. 26, 2024, 7:51 p.m. UTC | #2 
On Thu, Dec 26, 2024 at 11:41 AM kernel test robot <lkp@intel.com> wrote:
>
> Hi Suren,
>
> kernel test robot noticed the following build errors:
>
> [auto build test ERROR on 431614f1580a03c1a653340c55ea76bd12a9403f]
>
> url:    https://github.com/intel-lab-lkp/linux/commits/Suren-Baghdasaryan/mm-introduce-vma_start_read_locked-_nested-helpers/20241227-010925
> base:   431614f1580a03c1a653340c55ea76bd12a9403f
> patch link:    https://lore.kernel.org/r/20241226170710.1159679-14-surenb%40google.com
> patch subject: [PATCH v7 13/17] mm/debug: print vm_refcnt state when dumping the vma
> config: hexagon-randconfig-002-20241227 (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-lkp@intel.com/config)
> compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-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/oe-kbuild-all/202412270328.HiJX1mRt-lkp@intel.com/
>
> All errors (new ones prefixed by >>):
>
> >> mm/debug.c:189:54: error: no member named 'vm_refcnt' in 'struct vm_area_struct'

Ugh, ok. On architectures with ARCH_SUPPORTS_PER_VMA_LOCK=n this will
happen. Preparing a fix.

>      189 |                 vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
>          |                                                               ~~~  ^
>    include/linux/printk.h:514:35: note: expanded from macro 'pr_emerg'
>      514 |         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
>          |                                          ^~~~~~~~~~~
>    include/linux/printk.h:501:60: note: expanded from macro 'printk'
>      501 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
>          |                                                            ^~~~~~~~~~~
>    include/linux/printk.h:473:19: note: expanded from macro 'printk_index_wrap'
>      473 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
>          |                                 ^~~~~~~~~~~
>    1 error generated.
>
>
> vim +189 mm/debug.c
>
>    178
>    179  void dump_vma(const struct vm_area_struct *vma)
>    180  {
>    181          pr_emerg("vma %px start %px end %px mm %px\n"
>    182                  "prot %lx anon_vma %px vm_ops %px\n"
>    183                  "pgoff %lx file %px private_data %px\n"
>    184                  "flags: %#lx(%pGv) refcnt %x\n",
>    185                  vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
>    186                  (unsigned long)pgprot_val(vma->vm_page_prot),
>    187                  vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
>    188                  vma->vm_file, vma->vm_private_data,
>  > 189                  vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
>    190  }
>    191  EXPORT_SYMBOL(dump_vma);
>    192
>
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
Suren Baghdasaryan Dec. 26, 2024, 7:54 p.m. UTC | #3 
On Thu, Dec 26, 2024 at 11:51 AM Suren Baghdasaryan <surenb@google.com> wrote:
>
> On Thu, Dec 26, 2024 at 11:41 AM kernel test robot <lkp@intel.com> wrote:
> >
> > Hi Suren,
> >
> > kernel test robot noticed the following build errors:
> >
> > [auto build test ERROR on 431614f1580a03c1a653340c55ea76bd12a9403f]
> >
> > url:    https://github.com/intel-lab-lkp/linux/commits/Suren-Baghdasaryan/mm-introduce-vma_start_read_locked-_nested-helpers/20241227-010925
> > base:   431614f1580a03c1a653340c55ea76bd12a9403f
> > patch link:    https://lore.kernel.org/r/20241226170710.1159679-14-surenb%40google.com
> > patch subject: [PATCH v7 13/17] mm/debug: print vm_refcnt state when dumping the vma
> > config: hexagon-randconfig-002-20241227 (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-lkp@intel.com/config)
> > compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-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/oe-kbuild-all/202412270328.HiJX1mRt-lkp@intel.com/
> >
> > All errors (new ones prefixed by >>):
> >
> > >> mm/debug.c:189:54: error: no member named 'vm_refcnt' in 'struct vm_area_struct'
>
> Ugh, ok. On architectures with ARCH_SUPPORTS_PER_VMA_LOCK=n this will
> happen. Preparing a fix.

This error actually also requires CONFIG_DEBUG_VM=y.

>
> >      189 |                 vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
> >          |                                                               ~~~  ^
> >    include/linux/printk.h:514:35: note: expanded from macro 'pr_emerg'
> >      514 |         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
> >          |                                          ^~~~~~~~~~~
> >    include/linux/printk.h:501:60: note: expanded from macro 'printk'
> >      501 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
> >          |                                                            ^~~~~~~~~~~
> >    include/linux/printk.h:473:19: note: expanded from macro 'printk_index_wrap'
> >      473 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
> >          |                                 ^~~~~~~~~~~
> >    1 error generated.
> >
> >
> > vim +189 mm/debug.c
> >
> >    178
> >    179  void dump_vma(const struct vm_area_struct *vma)
> >    180  {
> >    181          pr_emerg("vma %px start %px end %px mm %px\n"
> >    182                  "prot %lx anon_vma %px vm_ops %px\n"
> >    183                  "pgoff %lx file %px private_data %px\n"
> >    184                  "flags: %#lx(%pGv) refcnt %x\n",
> >    185                  vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
> >    186                  (unsigned long)pgprot_val(vma->vm_page_prot),
> >    187                  vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
> >    188                  vma->vm_file, vma->vm_private_data,
> >  > 189                  vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
> >    190  }
> >    191  EXPORT_SYMBOL(dump_vma);
> >    192
> >
> > --
> > 0-DAY CI Kernel Test Service
> > https://github.com/intel/lkp-tests/wiki
Suren Baghdasaryan Dec. 26, 2024, 8:04 p.m. UTC | #4 
On Thu, Dec 26, 2024 at 11:54 AM Suren Baghdasaryan <surenb@google.com> wrote:
>
> On Thu, Dec 26, 2024 at 11:51 AM Suren Baghdasaryan <surenb@google.com> wrote:
> >
> > On Thu, Dec 26, 2024 at 11:41 AM kernel test robot <lkp@intel.com> wrote:
> > >
> > > Hi Suren,
> > >
> > > kernel test robot noticed the following build errors:
> > >
> > > [auto build test ERROR on 431614f1580a03c1a653340c55ea76bd12a9403f]
> > >
> > > url:    https://github.com/intel-lab-lkp/linux/commits/Suren-Baghdasaryan/mm-introduce-vma_start_read_locked-_nested-helpers/20241227-010925
> > > base:   431614f1580a03c1a653340c55ea76bd12a9403f
> > > patch link:    https://lore.kernel.org/r/20241226170710.1159679-14-surenb%40google.com
> > > patch subject: [PATCH v7 13/17] mm/debug: print vm_refcnt state when dumping the vma
> > > config: hexagon-randconfig-002-20241227 (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-lkp@intel.com/config)
> > > compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
> > > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241227/202412270328.HiJX1mRt-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/oe-kbuild-all/202412270328.HiJX1mRt-lkp@intel.com/
> > >
> > > All errors (new ones prefixed by >>):
> > >
> > > >> mm/debug.c:189:54: error: no member named 'vm_refcnt' in 'struct vm_area_struct'
> >
> > Ugh, ok. On architectures with ARCH_SUPPORTS_PER_VMA_LOCK=n this will
> > happen. Preparing a fix.
>
> This error actually also requires CONFIG_DEBUG_VM=y.

Fixup posted at
https://lore.kernel.org/all/20241226200335.1250078-1-surenb@google.com/

>
> >
> > >      189 |                 vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
> > >          |                                                               ~~~  ^
> > >    include/linux/printk.h:514:35: note: expanded from macro 'pr_emerg'
> > >      514 |         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
> > >          |                                          ^~~~~~~~~~~
> > >    include/linux/printk.h:501:60: note: expanded from macro 'printk'
> > >      501 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
> > >          |                                                            ^~~~~~~~~~~
> > >    include/linux/printk.h:473:19: note: expanded from macro 'printk_index_wrap'
> > >      473 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
> > >          |                                 ^~~~~~~~~~~
> > >    1 error generated.
> > >
> > >
> > > vim +189 mm/debug.c
> > >
> > >    178
> > >    179  void dump_vma(const struct vm_area_struct *vma)
> > >    180  {
> > >    181          pr_emerg("vma %px start %px end %px mm %px\n"
> > >    182                  "prot %lx anon_vma %px vm_ops %px\n"
> > >    183                  "pgoff %lx file %px private_data %px\n"
> > >    184                  "flags: %#lx(%pGv) refcnt %x\n",
> > >    185                  vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
> > >    186                  (unsigned long)pgprot_val(vma->vm_page_prot),
> > >    187                  vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
> > >    188                  vma->vm_file, vma->vm_private_data,
> > >  > 189                  vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
> > >    190  }
> > >    191  EXPORT_SYMBOL(dump_vma);
> > >    192
> > >
> > > --
> > > 0-DAY CI Kernel Test Service
> > > https://github.com/intel/lkp-tests/wiki
kernel test robot Dec. 26, 2024, 8:13 p.m. UTC | #5 
Hi Suren,

kernel test robot noticed the following build errors:

[auto build test ERROR on 431614f1580a03c1a653340c55ea76bd12a9403f]

url:    https://github.com/intel-lab-lkp/linux/commits/Suren-Baghdasaryan/mm-introduce-vma_start_read_locked-_nested-helpers/20241227-010925
base:   431614f1580a03c1a653340c55ea76bd12a9403f
patch link:    https://lore.kernel.org/r/20241226170710.1159679-14-surenb%40google.com
patch subject: [PATCH v7 13/17] mm/debug: print vm_refcnt state when dumping the vma
config: riscv-randconfig-001-20241227 (https://download.01.org/0day-ci/archive/20241227/202412270304.GtgNiDPd-lkp@intel.com/config)
compiler: riscv64-linux-gcc (GCC) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241227/202412270304.GtgNiDPd-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/oe-kbuild-all/202412270304.GtgNiDPd-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from include/asm-generic/bug.h:22,
                    from arch/riscv/include/asm/bug.h:83,
                    from include/linux/bug.h:5,
                    from arch/riscv/include/asm/cmpxchg.h:9,
                    from arch/riscv/include/asm/barrier.h:14,
                    from include/asm-generic/bitops/generic-non-atomic.h:7,
                    from include/linux/bitops.h:29,
                    from include/linux/kernel.h:23,
                    from mm/debug.c:9:
   mm/debug.c: In function 'dump_vma':
>> mm/debug.c:189:66: error: 'const struct vm_area_struct' has no member named 'vm_refcnt'
     189 |                 vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
         |                                                                  ^~
   include/linux/printk.h:473:33: note: in definition of macro 'printk_index_wrap'
     473 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
         |                                 ^~~~~~~~~~~
   include/linux/printk.h:514:9: note: in expansion of macro 'printk'
     514 |         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
         |         ^~~~~~
   mm/debug.c:181:9: note: in expansion of macro 'pr_emerg'
     181 |         pr_emerg("vma %px start %px end %px mm %px\n"
         |         ^~~~~~~~


vim +189 mm/debug.c

   178	
   179	void dump_vma(const struct vm_area_struct *vma)
   180	{
   181		pr_emerg("vma %px start %px end %px mm %px\n"
   182			"prot %lx anon_vma %px vm_ops %px\n"
   183			"pgoff %lx file %px private_data %px\n"
   184			"flags: %#lx(%pGv) refcnt %x\n",
   185			vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
   186			(unsigned long)pgprot_val(vma->vm_page_prot),
   187			vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
   188			vma->vm_file, vma->vm_private_data,
 > 189			vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
   190	}
   191	EXPORT_SYMBOL(dump_vma);
   192
diff mbox series

Patch

diff --git a/mm/debug.c b/mm/debug.c
index 95b6ab809c0e..68b3ba3cf603 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -181,12 +181,12 @@  void dump_vma(const struct vm_area_struct *vma)
 	pr_emerg("vma %px start %px end %px mm %px\n"
 		"prot %lx anon_vma %px vm_ops %px\n"
 		"pgoff %lx file %px private_data %px\n"
-		"flags: %#lx(%pGv)\n",
+		"flags: %#lx(%pGv) refcnt %x\n",
 		vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
 		(unsigned long)pgprot_val(vma->vm_page_prot),
 		vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
 		vma->vm_file, vma->vm_private_data,
-		vma->vm_flags, &vma->vm_flags);
+		vma->vm_flags, &vma->vm_flags, refcount_read(&vma->vm_refcnt));
 }
 EXPORT_SYMBOL(dump_vma);