Christian Brauner <[email protected]> writes: > I'm not sure why the build is complaining about how the union is initialized > here. This looks legitimate to me and I can't reproduce this locally with or > without the appended config. The struct introduced here is: > > #define UID_GID_MAP_MAX_EXTENTS 5 > > struct uid_gid_extent { > u32 first; > u32 lower_first; > u32 count; > }; > > struct uid_gid_map { /* 64 bytes -- 1 cache line */ > u32 nr_extents; > union { > struct uid_gid_extent extent[UID_GID_MAP_MAX_EXTENTS]; > struct { > struct uid_gid_extent *forward; > struct uid_gid_extent *reverse; > }; > }; > }; > > And the initialization in kernel/user.c which I didn't change looks correct. > But maybe I'm missing the point.
You may want to check your compiler version this feels like a compiler dependent error. It looks like gcc isn't happy about not having braces for the anonymous union of extent and the anonymouns structure that holds forward and reverse. FYI since I am commenting. I took a quick skim through your code today and at first glance everything looks good. The performance is nice and fast, and the changes look reasonable at first glance. I think there are some nits that can be picked but nothing yet that indicates the code is working incorrectly. Eric > On Thu, Oct 19, 2017 at 06:51:48AM +0800, kbuild test robot wrote: >> Hi Christian, >> >> [auto build test ERROR on linus/master] >> [also build test ERROR on v4.14-rc5 next-20171017] >> [if your patch is applied to the wrong git tree, please drop us a note to >> help improve the system] >> >> url: >> https://github.com/0day-ci/linux/commits/Christian-Brauner/user-namespace-use-union-in-g-u-idmap-struct/20171019-022142 >> config: x86_64-randconfig-a0-10190527 (attached as .config) >> compiler: gcc-4.4 (Debian 4.4.7-8) 4.4.7 >> reproduce: >> # save the attached .config to linux build tree >> make ARCH=x86_64 >> >> All error/warnings (new ones prefixed by >>): >> >> >> kernel/user.c:29: error: unknown field 'extent' specified in initializer >> >> kernel/user.c:30: error: unknown field 'first' specified in initializer >> >> kernel/user.c:30: warning: missing braces around initializer >> kernel/user.c:30: warning: (near initialization for >> 'init_user_ns.uid_map.<anonymous>.extent') >> >> kernel/user.c:31: error: unknown field 'lower_first' specified in >> >> initializer >> >> kernel/user.c:31: warning: excess elements in union initializer >> kernel/user.c:31: warning: (near initialization for >> 'init_user_ns.uid_map.<anonymous>') >> >> kernel/user.c:32: error: unknown field 'count' specified in initializer >> kernel/user.c:32: warning: excess elements in union initializer >> kernel/user.c:32: warning: (near initialization for >> 'init_user_ns.uid_map.<anonymous>') >> kernel/user.c:37: error: unknown field 'extent' specified in initializer >> kernel/user.c:38: error: unknown field 'first' specified in initializer >> kernel/user.c:39: error: unknown field 'lower_first' specified in >> initializer >> kernel/user.c:39: warning: excess elements in union initializer >> kernel/user.c:39: warning: (near initialization for >> 'init_user_ns.gid_map.<anonymous>') >> kernel/user.c:40: error: unknown field 'count' specified in initializer >> kernel/user.c:40: warning: excess elements in union initializer >> kernel/user.c:40: warning: (near initialization for >> 'init_user_ns.gid_map.<anonymous>') >> kernel/user.c:45: error: unknown field 'extent' specified in initializer >> kernel/user.c:46: error: unknown field 'first' specified in initializer >> kernel/user.c:47: error: unknown field 'lower_first' specified in >> initializer >> kernel/user.c:47: warning: excess elements in union initializer >> kernel/user.c:47: warning: (near initialization for >> 'init_user_ns.projid_map.<anonymous>') >> kernel/user.c:48: error: unknown field 'count' specified in initializer >> kernel/user.c:48: warning: excess elements in union initializer >> kernel/user.c:48: warning: (near initialization for >> 'init_user_ns.projid_map.<anonymous>') >> >> vim +/lower_first +31 kernel/user.c >> >> ^1da177e4 Linus Torvalds 2005-04-16 21 >> 59607db36 Serge E. Hallyn 2011-03-23 22 /* >> 59607db36 Serge E. Hallyn 2011-03-23 23 * userns count is 1 for root >> user, 1 for init_uts_ns, >> 59607db36 Serge E. Hallyn 2011-03-23 24 * and 1 for... ? >> 59607db36 Serge E. Hallyn 2011-03-23 25 */ >> aee16ce73 Pavel Emelyanov 2008-02-08 26 struct user_namespace >> init_user_ns = { >> 22d917d80 Eric W. Biederman 2011-11-17 27 .uid_map = { >> 22d917d80 Eric W. Biederman 2011-11-17 28 .nr_extents = 1, >> 22d917d80 Eric W. Biederman 2011-11-17 @29 .extent[0] = { >> 22d917d80 Eric W. Biederman 2011-11-17 @30 .first = 0, >> 22d917d80 Eric W. Biederman 2011-11-17 @31 .lower_first = >> 0, >> 4b06a81f1 Eric W. Biederman 2012-05-19 @32 .count = >> 4294967295U, >> 22d917d80 Eric W. Biederman 2011-11-17 33 }, >> 22d917d80 Eric W. Biederman 2011-11-17 34 }, >> 22d917d80 Eric W. Biederman 2011-11-17 35 .gid_map = { >> 22d917d80 Eric W. Biederman 2011-11-17 36 .nr_extents = 1, >> 22d917d80 Eric W. Biederman 2011-11-17 37 .extent[0] = { >> 22d917d80 Eric W. Biederman 2011-11-17 38 .first = 0, >> 22d917d80 Eric W. Biederman 2011-11-17 39 .lower_first = >> 0, >> 4b06a81f1 Eric W. Biederman 2012-05-19 40 .count = >> 4294967295U, >> 22d917d80 Eric W. Biederman 2011-11-17 41 }, >> 22d917d80 Eric W. Biederman 2011-11-17 42 }, >> f76d207a6 Eric W. Biederman 2012-08-30 43 .projid_map = { >> f76d207a6 Eric W. Biederman 2012-08-30 44 .nr_extents = 1, >> f76d207a6 Eric W. Biederman 2012-08-30 45 .extent[0] = { >> f76d207a6 Eric W. Biederman 2012-08-30 46 .first = 0, >> f76d207a6 Eric W. Biederman 2012-08-30 47 .lower_first = >> 0, >> f76d207a6 Eric W. Biederman 2012-08-30 48 .count = >> 4294967295U, >> f76d207a6 Eric W. Biederman 2012-08-30 49 }, >> f76d207a6 Eric W. Biederman 2012-08-30 50 }, >> c61a2810a Eric W. Biederman 2012-12-28 51 .count = ATOMIC_INIT(3), >> 783291e69 Eric W. Biederman 2011-11-17 52 .owner = GLOBAL_ROOT_UID, >> 783291e69 Eric W. Biederman 2011-11-17 53 .group = GLOBAL_ROOT_GID, >> 435d5f4bb Al Viro 2014-10-31 54 .ns.inum = PROC_USER_INIT_INO, >> 33c429405 Al Viro 2014-11-01 55 #ifdef CONFIG_USER_NS >> 33c429405 Al Viro 2014-11-01 56 .ns.ops = &userns_operations, >> 33c429405 Al Viro 2014-11-01 57 #endif >> 9cc46516d Eric W. Biederman 2014-12-02 58 .flags = USERNS_INIT_FLAGS, >> 6bd364d82 Xiao Guangrong 2013-12-13 59 #ifdef CONFIG_PERSISTENT_KEYRINGS >> 6bd364d82 Xiao Guangrong 2013-12-13 60 >> .persistent_keyring_register_sem = >> 6bd364d82 Xiao Guangrong 2013-12-13 61 >> __RWSEM_INITIALIZER(init_user_ns.persistent_keyring_register_sem), >> f36f8c75a David Howells 2013-09-24 62 #endif >> aee16ce73 Pavel Emelyanov 2008-02-08 63 }; >> aee16ce73 Pavel Emelyanov 2008-02-08 64 EXPORT_SYMBOL_GPL(init_user_ns); >> aee16ce73 Pavel Emelyanov 2008-02-08 65 >> >> :::::: The code at line 31 was first introduced by commit >> :::::: 22d917d80e842829d0ca0a561967d728eb1d6303 userns: Rework the >> user_namespace adding uid/gid mapping support >> >> :::::: TO: Eric W. Biederman <[email protected]> >> :::::: CC: Eric W. Biederman <[email protected]> >> >> --- >> 0-DAY kernel test infrastructure Open Source Technology Center >> https://lists.01.org/pipermail/kbuild-all Intel Corporation
