Re: [PATCH v3 net] dccp/tcp: fix ireq->opt races

Hi Eric,

[auto build test WARNING on net/master]

url:    https://github.com/0day-ci/linux/commits/Eric-Dumazet/dccp-tcp-fix-ireq-opt-races/20171021-034024
config: alpha-allmodconfig (attached as .config)
compiler: alpha-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=alpha 

All warnings (new ones prefixed by >>):

   In file included from arch/alpha/include/asm/atomic.h:6:0,
                    from include/linux/atomic.h:4,
                    from include/linux/rcupdate.h:38,
                    from net/ipv4/cipso_ipv4.c:40:
   net/ipv4/cipso_ipv4.c: In function 'cipso_v4_req_setattr':
   net/ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:47:15: note: in definition of macro 'xchg'
     __typeof__(*(ptr)) _x_ = (x);     \
                  ^~~

quoted

arch/alpha/include/asm/cmpxchg.h:47:27: warning: initialization makes integer from pointer without a cast [-Wint-conversion]

     __typeof__(*(ptr)) _x_ = (x);     \
                              ^
   net/ipv4/cipso_ipv4.c:1954:8: note: in expansion of macro 'xchg'
     opt = xchg(&req_inet->opt, opt);
           ^~~~
   net/ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:48:16: note: in definition of macro 'xchg'
     (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,  \
                   ^~~
   net/ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:48:31: note: in definition of macro 'xchg'
     (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,  \
                                  ^~~
   net/ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:49:15: note: in definition of macro 'xchg'
         sizeof(*(ptr)));   \
                  ^~~
   net/ipv4/cipso_ipv4.c: In function 'cipso_v4_req_delattr':
   net/ipv4/cipso_ipv4.c:2073:16: error: 'struct inet_request_sock' has no member named 'opt'
     opt = req_inet->opt;
                   ^~
   net/ipv4/cipso_ipv4.c:2077:27: error: 'struct inet_request_sock' has no member named 'opt'
     cipso_v4_delopt(&req_inet->opt);
                              ^~
--
   In file included from arch/alpha/include/asm/atomic.h:6:0,
                    from include/linux/atomic.h:4,
                    from include/linux/rcupdate.h:38,
                    from net//ipv4/cipso_ipv4.c:40:
   net//ipv4/cipso_ipv4.c: In function 'cipso_v4_req_setattr':
   net//ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:47:15: note: in definition of macro 'xchg'
     __typeof__(*(ptr)) _x_ = (x);     \
                  ^~~

quoted

arch/alpha/include/asm/cmpxchg.h:47:27: warning: initialization makes integer from pointer without a cast [-Wint-conversion]

     __typeof__(*(ptr)) _x_ = (x);     \
                              ^
   net//ipv4/cipso_ipv4.c:1954:8: note: in expansion of macro 'xchg'
     opt = xchg(&req_inet->opt, opt);
           ^~~~
   net//ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:48:16: note: in definition of macro 'xchg'
     (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,  \
                   ^~~
   net//ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:48:31: note: in definition of macro 'xchg'
     (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,  \
                                  ^~~
   net//ipv4/cipso_ipv4.c:1954:22: error: 'struct inet_request_sock' has no member named 'opt'
     opt = xchg(&req_inet->opt, opt);
                         ^
   arch/alpha/include/asm/cmpxchg.h:49:15: note: in definition of macro 'xchg'
         sizeof(*(ptr)));   \
                  ^~~
   net//ipv4/cipso_ipv4.c: In function 'cipso_v4_req_delattr':
   net//ipv4/cipso_ipv4.c:2073:16: error: 'struct inet_request_sock' has no member named 'opt'
     opt = req_inet->opt;
                   ^~
   net//ipv4/cipso_ipv4.c:2077:27: error: 'struct inet_request_sock' has no member named 'opt'
     cipso_v4_delopt(&req_inet->opt);
                              ^~

vim +47 arch/alpha/include/asm/cmpxchg.h

5ba840f9 Paul Gortmaker 2012-04-02  44  
5ba840f9 Paul Gortmaker 2012-04-02  45  #define xchg(ptr, x)							\
5ba840f9 Paul Gortmaker 2012-04-02  46  ({									\
5ba840f9 Paul Gortmaker 2012-04-02 @47  	__typeof__(*(ptr)) _x_ = (x);					\
5ba840f9 Paul Gortmaker 2012-04-02  48  	(__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_,		\
5ba840f9 Paul Gortmaker 2012-04-02  49  				 sizeof(*(ptr)));			\
5ba840f9 Paul Gortmaker 2012-04-02  50  })
5ba840f9 Paul Gortmaker 2012-04-02  51  

:::::: The code at line 47 was first introduced by commit
:::::: 5ba840f9da1ff96e0c6e982608a9e80e35333cc5 alpha: fix build failures from system.h dismemberment

:::::: TO: Paul Gortmaker [off-list ref]
:::::: CC: Paul Gortmaker [off-list ref]

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