diff mbox series

[net-next,08/19] drop_monitor: add net device refcount tracker

Message ID 20211202032139.3156411-9-eric.dumazet@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series net: add preliminary netdev refcount tracking | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count fail Series longer than 15 patches (and no cover letter)
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit fail Errors and warnings before: 382 this patch: 384
netdev/cc_maintainers warning 2 maintainers not CCed: jiri@nvidia.com nhorman@tuxdriver.com
netdev/build_clang fail Errors and warnings before: 46 this patch: 32
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn fail Errors and warnings before: 520 this patch: 522
netdev/checkpatch warning WARNING: line length of 86 exceeds 80 columns
netdev/kdoc fail Errors and warnings before: 14 this patch: 15
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet Dec. 2, 2021, 3:21 a.m. UTC 
From: Eric Dumazet <edumazet@google.com>

We want to track all dev_hold()/dev_put() to ease leak hunting.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/devlink.h   | 3 +++
 net/core/drop_monitor.c | 4 ++--
 2 files changed, 5 insertions(+), 2 deletions(-)

Comments

kernel test robot Dec. 2, 2021, 5:40 a.m. UTC | #1 
Hi Eric,

I love your patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]

url:    https://github.com/0day-ci/linux/commits/Eric-Dumazet/net-add-preliminary-netdev-refcount-tracking/20211202-112353
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 8057cbb8335cf6d419866737504473833e1d128a
config: nds32-allyesconfig (https://download.01.org/0day-ci/archive/20211202/202112021345.IlporM5t-lkp@intel.com/config)
compiler: nds32le-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/6b336d0b301ebb1097132101a9e3bd01f71c40d4
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Eric-Dumazet/net-add-preliminary-netdev-refcount-tracking/20211202-112353
        git checkout 6b336d0b301ebb1097132101a9e3bd01f71c40d4
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=nds32 SHELL=/bin/bash net/core/

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

All warnings (new ones prefixed by >>):

   net/core/drop_monitor.c: In function 'net_dm_hw_metadata_free':
>> net/core/drop_monitor.c:869:47: warning: passing argument 2 of 'dev_put_track' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
     869 |         dev_put_track(hw_metadata->input_dev, &hw_metadata->dev_tracker);
         |                                               ^~~~~~~~~~~~~~~~~~~~~~~~~
   In file included from net/core/drop_monitor.c:10:
   include/linux/netdevice.h:3863:53: note: expected 'struct ref_tracker **' but argument is of type 'struct ref_tracker * const*'
    3863 |                                  netdevice_tracker *tracker)
         |                                  ~~~~~~~~~~~~~~~~~~~^~~~~~~


vim +869 net/core/drop_monitor.c

   865	
   866	static void
   867	net_dm_hw_metadata_free(const struct devlink_trap_metadata *hw_metadata)
   868	{
 > 869		dev_put_track(hw_metadata->input_dev, &hw_metadata->dev_tracker);
   870		kfree(hw_metadata->fa_cookie);
   871		kfree(hw_metadata->trap_name);
   872		kfree(hw_metadata->trap_group_name);
   873		kfree(hw_metadata);
   874	}
   875	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Eric Dumazet Dec. 2, 2021, 5:57 a.m. UTC | #2 
On Wed, Dec 1, 2021 at 9:41 PM kernel test robot <lkp@intel.com> wrote:
>
> Hi Eric,
>
> I love your patch! Perhaps something to improve:
>
> [auto build test WARNING on net-next/master]
>
> url:    https://github.com/0day-ci/linux/commits/Eric-Dumazet/net-add-preliminary-netdev-refcount-tracking/20211202-112353
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 8057cbb8335cf6d419866737504473833e1d128a
> config: nds32-allyesconfig (https://download.01.org/0day-ci/archive/20211202/202112021345.IlporM5t-lkp@intel.com/config)
> compiler: nds32le-linux-gcc (GCC) 11.2.0
> reproduce (this is a W=1 build):
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # https://github.com/0day-ci/linux/commit/6b336d0b301ebb1097132101a9e3bd01f71c40d4
>         git remote add linux-review https://github.com/0day-ci/linux
>         git fetch --no-tags linux-review Eric-Dumazet/net-add-preliminary-netdev-refcount-tracking/20211202-112353
>         git checkout 6b336d0b301ebb1097132101a9e3bd01f71c40d4
>         # save the config file to linux build tree
>         mkdir build_dir
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=nds32 SHELL=/bin/bash net/core/
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
>
> All warnings (new ones prefixed by >>):
>
>    net/core/drop_monitor.c: In function 'net_dm_hw_metadata_free':
> >> net/core/drop_monitor.c:869:47: warning: passing argument 2 of 'dev_put_track' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
>      869 |         dev_put_track(hw_metadata->input_dev, &hw_metadata->dev_tracker);
>          |                                               ^~~~~~~~~~~~~~~~~~~~~~~~~
>    In file included from net/core/drop_monitor.c:10:
>    include/linux/netdevice.h:3863:53: note: expected 'struct ref_tracker **' but argument is of type 'struct ref_tracker * const*'
>     3863 |                                  netdevice_tracker *tracker)
>          |                                  ~~~~~~~~~~~~~~~~~~~^~~~~~~
>
>
> vim +869 net/core/drop_monitor.c
>
>    865
>    866  static void
>    867  net_dm_hw_metadata_free(const struct devlink_trap_metadata *hw_metadata)

Yep, I have removed this not really useful  const qualifier

net_dm_hw_metadata_free(struct devlink_trap_metadata *hw_metadata)
...


>    868  {
>  > 869          dev_put_track(hw_metadata->input_dev, &hw_metadata->dev_tracker);
>    870          kfree(hw_metadata->fa_cookie);
>    871          kfree(hw_metadata->trap_name);
>    872          kfree(hw_metadata->trap_group_name);
>    873          kfree(hw_metadata);
>    874  }
>    875
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/include/net/devlink.h b/include/net/devlink.h
index 043fcec8b0aadf041aba35b8339c93ac9336b551..09b75fdfa74e268aaeb05ec640fd76ec5ba777ac 100644
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -670,7 +670,10 @@  struct devlink_health_reporter_ops {
 struct devlink_trap_metadata {
 	const char *trap_name;
 	const char *trap_group_name;
+
 	struct net_device *input_dev;
+	netdevice_tracker dev_tracker;
+
 	const struct flow_action_cookie *fa_cookie;
 	enum devlink_trap_type trap_type;
 };
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index 49442cae6f69d5e9d93d00b53ab8f5a0563c1d37..dff13c208c1dafac26c3180a37e6e3be5f8fa744 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -850,7 +850,7 @@  net_dm_hw_metadata_copy(const struct devlink_trap_metadata *metadata)
 	}
 
 	hw_metadata->input_dev = metadata->input_dev;
-	dev_hold(hw_metadata->input_dev);
+	dev_hold_track(hw_metadata->input_dev, &hw_metadata->dev_tracker, GFP_ATOMIC);
 
 	return hw_metadata;
 
@@ -866,7 +866,7 @@  net_dm_hw_metadata_copy(const struct devlink_trap_metadata *metadata)
 static void
 net_dm_hw_metadata_free(const struct devlink_trap_metadata *hw_metadata)
 {
-	dev_put(hw_metadata->input_dev);
+	dev_put_track(hw_metadata->input_dev, &hw_metadata->dev_tracker);
 	kfree(hw_metadata->fa_cookie);
 	kfree(hw_metadata->trap_name);
 	kfree(hw_metadata->trap_group_name);