Subject: Re: [netdev] Build failure on powerpc

From: Michael Ellerman <[email-masked]>
Date: Thu, 29 Feb 2024 13:22:01 +1100

Tasmiya Nalatwad <[email-masked]> writes:
> Greetings,
>
> [netdev] Build failure on powerpc
> latest netdev 6.8.0-rc5-auto-g1ce7d306ea63 fails to build on powerpc 
> below traces

Please include the defconfig you're building, and the toolchain
versions, in reports like this.

I wasn't able to reproduce this failure here.

cheers

> --- 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]
>   }
>
>
> Reverting the below commit fixes the problem
>
> commit 0d60d8df6f493bb46bf5db40d39dd60a1bafdd4e
>      dpll: rely on rcu for netdev_dpll_pin()
>
> -- 
> Regards,
> Tasmiya Nalatwad
> IBM Linux Technology Center