Re: [revert 0d60d8df6f49] [net/net-next] [6.8-rc5] Build Failure

[Tasmiya Nalatwad <tasmiya@linux.vnet.ibm.com>]

Greetings,

I have tried the patch provided below. Moving struct to file 
"net/core/rtnetlink.c" is not resolving the problem. Please find the 
below traces.

--- Traces ---

In file included from ./include/linux/rbtree.h:24,
                  from ./include/linux/mm_types.h:11,
                  from ./include/linux/mmzone.h:22,
                  from ./include/linux/gfp.h:7,
                  from ./include/linux/umh.h:4,
                  from ./include/linux/kmod.h:9,
                  from ./include/linux/module.h:17,
                  from net/core/rtnetlink.c:17:
net/core/rtnetlink.c: In function ‘netdev_dpll_pin’:
./include/linux/rcupdate.h:439:9: error: dereferencing pointer to 
incomplete type ‘struct dpll_pin’
   typeof(*p) *local = (typeof(*p) *__force)READ_ONCE(p); \
          ^
./include/linux/rcupdate.h:587:2: note: in expansion of macro 
‘__rcu_dereference_check’
   __rcu_dereference_check((p), __UNIQUE_ID(rcu), \
   ^~~~~~~~~~~~~~~~~~~~~~~
./include/linux/rtnetlink.h:70:2: note: in expansion of macro 
‘rcu_dereference_check’
   rcu_dereference_check(p, lockdep_rtnl_is_held())
   ^~~~~~~~~~~~~~~~~~~~~
net/core/rtnetlink.c:1059:15: note: in expansion of macro 
‘rcu_dereference_rtnl’
         return rcu_dereference_rtnl(dev->dpll_pin);
                ^~~~~~~~~~~~~~~~~~~~
   CC      crypto/algboss.o
net/core/rtnetlink.c:1063:1: error: control reaches end of non-void 
function [-Werror=return-type]
  }
  ^
   CC      crypto/authenc.o
   CC      crypto/authencesn.o
   CC      crypto/af_alg.o
   CC      crypto/algif_hash.o
   CC      crypto/algif_skcipher.o
   CC      crypto/algif_rng.o
   CC      crypto/algif_aead.o
   AR      arch/powerpc/kernel/built-in.a
cc1: some warnings being treated as errors
make[4]: *** [scripts/Makefile.build:243: net/core/rtnetlink.o] Error 1
make[4]: *** Waiting for unfinished jobs....
   CC      lib/kobject_uevent.o
   AR      drivers/net/mdio/built-in.a
   AR      net/802/built-in.a
   AR      drivers/connector/built-in.a
   CC      lib/vsprintf.o
   AR      ipc/built-in.a
   AR      net/nsh/built-in.a
   CC      lib/dynamic_debug.o
In file included from ./arch/powerpc/include/generated/asm/rwonce.h:1,
                  from ./include/linux/compiler.h:251,
                  from ./include/linux/instrumented.h:10,
                  from ./include/linux/uaccess.h:6,
                  from net/core/dev.c:71:
net/core/dev.c: In function ‘netdev_dpll_pin_assign’:
./include/linux/rcupdate.h:462:36: error: dereferencing pointer to 
incomplete type ‘struct dpll_pin’
  #define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
                                     ^~~~
./include/asm-generic/rwonce.h:55:33: note: in definition of macro 
‘__WRITE_ONCE’
   *(volatile typeof(x) *)&(x) = (val);    \
                                  ^~~
./arch/powerpc/include/asm/barrier.h:76:2: note: in expansion of macro 
‘WRITE_ONCE’
   WRITE_ONCE(*p, v);      \
   ^~~~~~~~~~
./include/asm-generic/barrier.h:172:55: note: in expansion of macro 
‘__smp_store_release’
  #define smp_store_release(p, v) do { kcsan_release(); 
__smp_store_release(p, v); } while (0)
^~~~~~~~~~~~~~~~~~~
./include/linux/rcupdate.h:503:3: note: in expansion of macro 
‘smp_store_release’
    smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
    ^~~~~~~~~~~~~~~~~
./include/linux/rcupdate.h:503:25: note: in expansion of macro 
‘RCU_INITIALIZER’
    smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
                          ^~~~~~~~~~~~~~~
net/core/dev.c:9081:2: note: in expansion of macro ‘rcu_assign_pointer’
   rcu_assign_pointer(dev->dpll_pin, dpll_pin);
   ^~~~~~~~~~~~~~~~~~

On 2/28/24 20:13, Eric Dumazet wrote:
> On Wed, Feb 28, 2024 at 3:07 PM Vadim Fedorenko
> <vadim.fedorenko@linux.dev> wrote:
>> On 28/02/2024 11:09, Tasmiya Nalatwad wrote:
>>> Greetings,
>>>
>>> [revert 0d60d8df6f49] [net/net-next] [6.8-rc5] Build Failure
>>>
>>> Reverting below commit fixes the issue
>>>
>>> commit 0d60d8df6f493bb46bf5db40d39dd60a1bafdd4e
>>>       dpll: rely on rcu for netdev_dpll_pin()
>>>
>>> --- Traces ---
>>>
>>> ./include/linux/dpll.h: In function ‘netdev_dpll_pin’:
>>> ./include/linux/rcupdate.h:439:9: error: dereferencing pointer to
>>> incomplete type ‘struct dpll_pin’
>>>     typeof(*p) *local = (typeof(*p) *__force)READ_ONCE(p); \
>>>            ^
>>> ./include/linux/rcupdate.h:587:2: note: in expansion of macro
>>> ‘__rcu_dereference_check’
>>>     __rcu_dereference_check((p), __UNIQUE_ID(rcu), \
>>>     ^~~~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/rtnetlink.h:70:2: note: in expansion of macro
>>> ‘rcu_dereference_check’
>>>     rcu_dereference_check(p, lockdep_rtnl_is_held())
>>>     ^~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/dpll.h:175:9: note: in expansion of macro
>>> ‘rcu_dereference_rtnl’
>>>     return rcu_dereference_rtnl(dev->dpll_pin);
>>>            ^~~~~~~~~~~~~~~~~~~~
>>> make[4]: *** [scripts/Makefile.build:243: drivers/dpll/dpll_core.o] Error 1
>>> make[4]: *** Waiting for unfinished jobs....
>>>     AR      net/mpls/built-in.a
>>>     AR      net/l3mdev/built-in.a
>>> In file included from ./include/linux/rbtree.h:24,
>>>                    from ./include/linux/mm_types.h:11,
>>>                    from ./include/linux/mmzone.h:22,
>>>                    from ./include/linux/gfp.h:7,
>>>                    from ./include/linux/umh.h:4,
>>>                    from ./include/linux/kmod.h:9,
>>>                    from ./include/linux/module.h:17,
>>>                    from drivers/dpll/dpll_netlink.c:9:
>>> ./include/linux/dpll.h: In function ‘netdev_dpll_pin’:
>>> ./include/linux/rcupdate.h:439:9: error: dereferencing pointer to
>>> incomplete type ‘struct dpll_pin’
>>>     typeof(*p) *local = (typeof(*p) *__force)READ_ONCE(p); \
>>>            ^
>>> ./include/linux/rcupdate.h:587:2: note: in expansion of macro
>>> ‘__rcu_dereference_check’
>>>     __rcu_dereference_check((p), __UNIQUE_ID(rcu), \
>>>     ^~~~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/rtnetlink.h:70:2: note: in expansion of macro
>>> ‘rcu_dereference_check’
>>>     rcu_dereference_check(p, lockdep_rtnl_is_held())
>>>     ^~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/dpll.h:175:9: note: in expansion of macro
>>> ‘rcu_dereference_rtnl’
>>>     return rcu_dereference_rtnl(dev->dpll_pin);
>>>            ^~~~~~~~~~~~~~~~~~~~
>>> make[4]: *** [scripts/Makefile.build:243: drivers/dpll/dpll_netlink.o]
>>> Error 1
>>> make[3]: *** [scripts/Makefile.build:481: drivers/dpll] Error 2
>>> make[3]: *** Waiting for unfinished jobs....
>>> In file included from ./arch/powerpc/include/generated/asm/rwonce.h:1,
>>>                    from ./include/linux/compiler.h:251,
>>>                    from ./include/linux/instrumented.h:10,
>>>                    from ./include/linux/uaccess.h:6,
>>>                    from net/core/dev.c:71:
>>> net/core/dev.c: In function ‘netdev_dpll_pin_assign’:
>>> ./include/linux/rcupdate.h:462:36: error: dereferencing pointer to
>>> incomplete type ‘struct dpll_pin’
>>>    #define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v)
>>>                                       ^~~~
>>> ./include/asm-generic/rwonce.h:55:33: note: in definition of macro
>>> ‘__WRITE_ONCE’
>>>     *(volatile typeof(x) *)&(x) = (val);    \
>>>                                    ^~~
>>> ./arch/powerpc/include/asm/barrier.h:76:2: note: in expansion of macro
>>> ‘WRITE_ONCE’
>>>     WRITE_ONCE(*p, v);      \
>>>     ^~~~~~~~~~
>>> ./include/asm-generic/barrier.h:172:55: note: in expansion of macro
>>> ‘__smp_store_release’
>>>    #define smp_store_release(p, v) do { kcsan_release();
>>> __smp_store_release(p, v); } while (0)
>>> ^~~~~~~~~~~~~~~~~~~
>>> ./include/linux/rcupdate.h:503:3: note: in expansion of macro
>>> ‘smp_store_release’
>>>      smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
>>>      ^~~~~~~~~~~~~~~~~
>>> ./include/linux/rcupdate.h:503:25: note: in expansion of macro
>>> ‘RCU_INITIALIZER’
>>>      smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \
>>>                            ^~~~~~~~~~~~~~~
>>> net/core/dev.c:9081:2: note: in expansion of macro ‘rcu_assign_pointer’
>>>     rcu_assign_pointer(dev->dpll_pin, dpll_pin);
>>>     ^~~~~~~~~~~~~~~~~~
>>> make[4]: *** [scripts/Makefile.build:243: net/core/dev.o] Error 1
>>> make[4]: *** Waiting for unfinished jobs....
>>>     AR      drivers/net/ethernet/built-in.a
>>>     AR      drivers/net/built-in.a
>>>     AR      net/dcb/built-in.a
>>>     AR      net/netlabel/built-in.a
>>>     AR      net/strparser/built-in.a
>>>     AR      net/handshake/built-in.a
>>>     GEN     lib/test_fortify.log
>>>     AR      net/8021q/built-in.a
>>>     AR      net/nsh/built-in.a
>>>     AR      net/unix/built-in.a
>>>     CC      lib/string.o
>>>     AR      net/packet/built-in.a
>>>     AR      net/switchdev/built-in.a
>>>     AR      lib/lib.a
>>>     AR      net/mptcp/built-in.a
>>>     AR      net/devlink/built-in.a
>>> In file included from ./include/linux/rbtree.h:24,
>>>                    from ./include/linux/mm_types.h:11,
>>>                    from ./include/linux/mmzone.h:22,
>>>                    from ./include/linux/gfp.h:7,
>>>                    from ./include/linux/umh.h:4,
>>>                    from ./include/linux/kmod.h:9,
>>>                    from ./include/linux/module.h:17,
>>>                    from net/core/rtnetlink.c:17:
>>> ./include/linux/dpll.h: In function ‘netdev_dpll_pin’:
>>> ./include/linux/rcupdate.h:439:9: error: dereferencing pointer to
>>> incomplete type ‘struct dpll_pin’
>>>     typeof(*p) *local = (typeof(*p) *__force)READ_ONCE(p); \
>>>            ^
>>> ./include/linux/rcupdate.h:587:2: note: in expansion of macro
>>> ‘__rcu_dereference_check’
>>>     __rcu_dereference_check((p), __UNIQUE_ID(rcu), \
>>>     ^~~~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/rtnetlink.h:70:2: note: in expansion of macro
>>> ‘rcu_dereference_check’
>>>     rcu_dereference_check(p, lockdep_rtnl_is_held())
>>>     ^~~~~~~~~~~~~~~~~~~~~
>>> ./include/linux/dpll.h:175:9: note: in expansion of macro
>>> ‘rcu_dereference_rtnl’
>>>     return rcu_dereference_rtnl(dev->dpll_pin);
>>>            ^~~~~~~~~~~~~~~~~~~~
>>> In file included from net/core/rtnetlink.c:60:
>>> ./include/linux/dpll.h:179:1: error: control reaches end of non-void
>>> function [-Werror=return-type]
>>>    }
>>>
>> Hi, Eric!
>>
>> Looks like we have to move struct dpll_pin definition to
>> include/linux/dpll.h to have this fixed, right?
>>
> No idea what is wrong. Is it powerpc specific ? Some compiler version ?
>
> netdev_dpll_pin() could be moved to net/core/rtnetlink.c, this is the only user.
>
> diff --git a/include/linux/dpll.h b/include/linux/dpll.h
> index 4ec2fe9caf5a3f284afd0cfe4fc7c2bf42cbbc60..72d21e710d7f201d2fc57bb3a32b4bc0ff2b1749
> 100644
> --- a/include/linux/dpll.h
> +++ b/include/linux/dpll.h
> @@ -169,13 +169,4 @@ int dpll_device_change_ntf(struct dpll_device *dpll);
>
>   int dpll_pin_change_ntf(struct dpll_pin *pin);
>
> -static inline struct dpll_pin *netdev_dpll_pin(const struct net_device *dev)
> -{
> -#if IS_ENABLED(CONFIG_DPLL)
> -       return rcu_dereference_rtnl(dev->dpll_pin);
> -#else
> -       return NULL;
> -#endif
> -}
> -
>   #endif
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 9c4f427f3a5057b52ec05405e8b15b8ca2246b4b..32dc601fd8ca66dfcd3cb8f38b533314de02d1d2
> 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -1053,6 +1053,15 @@ static size_t rtnl_devlink_port_size(const
> struct net_device *dev)
>          return size;
>   }
>
> +static struct dpll_pin *netdev_dpll_pin(const struct net_device *dev)
> +{
> +#if IS_ENABLED(CONFIG_DPLL)
> +       return rcu_dereference_rtnl(dev->dpll_pin);
> +#else
> +       return NULL;
> +#endif
> +}
> +
>   static size_t rtnl_dpll_pin_size(const struct net_device *dev)
>   {
>          size_t size = nla_total_size(0); /* nest IFLA_DPLL_PIN */

-- 
Regards,
Tasmiya Nalatwad
IBM Linux Technology Center