RE: [PATCH] mm/sparse: only sub-section aligned range would be populated

["Xia, Hui" <hui.xia@intel.com>]

>-----Original Message-----
>From: Wei Yang <richard.weiyang@linux.alibaba.com>
>Sent: 2020年7月1日 19:58
>To: lkp <lkp@intel.com>
>Cc: Wei Yang <richard.weiyang@linux.alibaba.com>; Williams, Dan J
><dan.j.williams@intel.com>; akpm@linux-foundation.org; kbuild-all@lists.01.org;
>clang-built-linux@googlegroups.com; linux-mm@kvack.org; linux-
>kernel@vger.kernel.org
>Subject: Re: [PATCH] mm/sparse: only sub-section aligned range would be
>populated
>
>On Wed, Jul 01, 2020 at 02:11:10AM +0800, kernel test robot wrote:
>>Hi Wei,
>>
>>Thank you for the patch! Perhaps something to improve:
>>
>>[auto build test WARNING on mmotm/master]
>>
>>url:    https://github.com/0day-ci/linux/commits/Wei-Yang/mm-sparse-only-
>sub-section-aligned-range-would-be-populated/20200630-101713
>>base:   git://git.cmpxchg.org/linux-mmotm.git master
>>config: x86_64-allnoconfig (attached as .config)
>>compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project
>>cf1d04484344be52ada8178e41d18fd15a9b880c)
>>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
>>        # install x86_64 cross compiling tool for clang build
>>        # apt-get install binutils-x86-64-linux-gnu
>>        # save the attached .config to linux build tree
>>        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross
>>ARCH=x86_64
>>
>>If you fix the issue, kindly add following tag as appropriate
>>Reported-by: kernel test robot <lkp@intel.com>
>>
>
>Sorry, I don't follow up with this error report.
>
>It looks like a build error, while I just removes some check and the build pass from
>my side. Confused with this error report.
It is false positive. Please ignore. Sorry for inconvenience.
The report complains about " warning: no previous prototype for function 'devkmsg_sysctl_set_loglvl'" which is not caused by commit in this report. We will investigate and fix in 0-day side.

>
>>All warnings (new ones prefixed by >>):
>>
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>   case 1: ^
>>   include/linux/signal.h:177:1: warning: unannotated fall-through between
>switch labels
>>   _SIG_SET_OP(signotset, _sig_not)
>>   ^
>>   include/linux/signal.h:167:2: note: expanded from macro '_SIG_SET_OP'
>>   case 2: = ^
>>   include/linux/signal.h:177:1: warning: unannotated fall-through between
>switch labels
>>   include/linux/signal.h:169:2: note: expanded from macro '_SIG_SET_OP'
>>   case 1: = ^
>>   include/linux/signal.h:190:2: warning: unannotated fall-through between
>switch labels
>>   case 1: = 0;
>>   ^
>>   include/linux/jhash.h:95:2: note: insert '__attribute__((fallthrough));' to silence
>this warning
>>   case 6: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:95:2: note: insert 'break;' to avoid fall-through
>>   case 6: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:96:2: warning: unannotated fall-through between switch
>labels
>>   case 5: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   15include/linux/signal.h:190:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>   case 1: = 0;
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/signal.h:190:2: note: insert 'break;' to avoid fall-through
>>   case 1: = 0;
>>   ^
>>   break;
>>   include/linux/signal.h:203:2: warninginclude/linux/jhash.h:96:2: note: insert
>'__attribute__((fallthrough));' to silence this warning
>>   case 5: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:96:2: note: insert 'break;' to avoid fall-through
>>   case 5: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:97:2: warning: unannotated fall-through between switch
>labels
>>   case 4: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   : unannotated fall-through between switch labels
>>   case 1: = -1;
>>   ^
>>   warnings generated.
>>   include/linux/signal.h:203:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>   case 1: = -1;
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/signal.h:15203:2: note: insert 'break;' to avoid fall-through
>>   case 1: = -1;
>>   ^
>>   break;
>>   include/linux/jhash.h:97:2: note: insert '__attribute__((fallthrough));' to silence
>this warning
>>   case 4: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:97:2: note: insert 'break;' to avoid fall-through
>>   case 4: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:98:2: warning: unannotated fall-through between switch
>labels
>>   case 3: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   include/linux/signal.h:233:2: warning: unannotated fall-through between
>switch labels
>>   case 1: ;
>>   ^
>>   warnings generated.
>>   In file included from kernel/printk/printk.c:61:
>>   kernel/printk/internal.h:54:20: warninginclude/linux/jhash.h:98:2: note: insert
>'__attribute__((fallthrough));' to silence this warning
>>   case 3: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:98:2: note: no previous prototype for function
>'vprintk_func'
>>   __printf(1, 0) int vprintk_func(const char va_list args) { return 0; }
>>   ^
>>   kernel/printk/internal.h: insert 'break;' to avoid fall-through
>>   case 3: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:99:2: warning: unannotated fall-through between switch
>labels
>>   case 2: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   :54:16: note: declare 'static' if the function is not intended to be used outside
>of this translation unit
>>   __printf(1, 0) int vprintk_func(const char va_list args) { return 0; }
>>   ^
>>   static
>>   kernel/printk/printk.cinclude/linux/signal.h:233:2: note: insert
>'__attribute__((fallthrough));' to silence this warning
>>   case 1: ;
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/signal.h:233:2: note: insert 'break;' to avoid fall-through
>>   case 1: ;
>>   ^
>>   break;
>>   include/linux/signal.h:245:2: warning: unannotated fall-through between
>switch labels
>>   case 1: ;
>>   ^
>>>> :165:5: warning: no previous prototype for function
>'devkmsg_sysctl_set_loglvl'
>>   int devkmsg_sysctl_set_loglvl(struct ctl_table int write,
>>   ^
>>   kernel/printk/printk.c:165:1: note: declare 'static' if the function is not
>intended to be used outside of this translation unit
>>   int devkmsg_sysctl_set_loglvl(struct ctl_table int write,
>>   ^
>>   static
>>   include/linux/jhash.h:99:2: note: insert '__attribute__((fallthrough));' to silence
>this warning
>>   case 2: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:99:2: note: insert 'break;' to avoid fall-through
>>   case 2: a += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:100:2: warning: unannotated fall-through between
>switch labels
>>   case 1: a +=
>>   ^
>>   include/linux/signal.h:245:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>   case 1: ;
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/signal.h:245:2: note: insert 'break;' to avoid fall-through
>>   case 1: ;
>>   ^
>>   break;
>>   kernel/printk/printk.cinclude/linux/jhash.h:100:2: note: insert
>'__attribute__((fallthrough));' to silence this warning
>>   case 1: a +=
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:100:2: note: insert 'break;' to avoid fall-through
>>   case 1: a +=
>>   ^
>>   break;
>>   include/linux/jhash.h:102:2: warning: unannotated fall-through between
>switch labels
>>   case 0: /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var Nothing left to add arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/
>kernel/ lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   include/linux/jhash.h:102:2: note: insert 'break;' to avoid fall-through
>>   case 0: /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var Nothing left to add arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/
>kernel/ lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   :2406:10: warning: 'sprintf' will always overflow; destination buffer has size 0,
>but format string expands to at least 33
>>   len = sprintf(text,
>>   ^
>>   include/linux/jhash.h:136:2: warning: unannotated fall-through between
>switch labels
>>   case 2: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   include/linux/jhash.h:136:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>   case 2: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   __attribute__((fallthrough));
>>   include/linux/jhash.h:136:2: note: insert 'break;' to avoid fall-through
>>   case 2: b += /Dockerfile /Gemfile /Gemfile.lock /bin /boot /c /cephfs /dev /etc
>/home /htmldocs /include /kbuild /lib /lib32 /lib64 /libx32 /lkp-cloud /lkp-src
>/media /mnt /opt /patch /pkg /proc /root /run /sbin /share /srv /sys /tmp /usr
>/var fall through arch/ block/ certs/ crypto/ drivers/ fs/ include/ init/ ipc/ kernel/
>lib/ mm/ net/ scripts/ security/ sound/ source/ tools/ usr/ virt/
>>   ^
>>   break;
>>   include/linux/jhash.h:137:2: warning: unannotated fall-through between
>switch labels
>>   case 1: a +=
>>   ^
>>   In file included from kernel/capability.c:13:
>>   In file included from include/linux/audit.h:13:
>>   In file included from include/linux/ptrace.h:7:
>>   In file included from include/linux/sched/signal.h:6:
>>   include/linux/signal.h:147:1: warning: unannotated fall-through between
>switch labels
>>   _SIG_SET_BINOP(sigorsets, _sig_or)
>>   ^
>>   include/linux/signal.h:133:2: note: expanded from macro '_SIG_SET_BINOP'
>>   case 2: ^
>>   include/linux/signal.h:147:1: warning: unannotated fall-through between
>switch labels
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>   case 1: ^
>>   include/linux/signal.h:150:1: warning: unannotated fall-through between
>switch labels
>>   _SIG_SET_BINOP(sigandsets, _sig_and)
>>   ^
>>   include/linux/signal.h:133:2:In file included from note: expanded from macro
>'_SIG_SET_BINOP'
>>   case 2: ^
>>   include/linux/signal.h:150:1: warning: unannotated fall-through between
>switch labels
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>   case 1: ^
>>   include/linux/signal.h:153:1: warning: unannotated fall-through between
>switch labels
>>   _SIG_SET_BINOP(sigandnsets, _sig_andn)
>>   ^
>>   include/linux/signal.h:133:2: note: expanded from macro '_SIG_SET_BINOP'
>>   case 2: kernel/sysctl_binary.c:15:
>>   In file included from include/linux/netdevice.h:37:
>>   In file included from include/linux/ethtool.h:18:
>>   In file included from include/uapi/linux/ethtool.h:19:
>>   In file included from include/linux/if_ether.h:19:
>>   include/linux/skbuff.h:3690:2: warning: unannotated fall-through between
>switch labels
>>   case 24: diffs |= __it_diff(a, b, 64);
>>   ^
>>--
>>           ^
>>           __attribute__((fallthrough));
>>   include/linux/mm.h:166:2: note: insert 'break;' to avoid fall-through
>>           case 56:
>>           ^
>>           break;
>>   In file included from kernel/printk/printk.c:36:
>>   In file included from include/linux/syscalls.h:76:
>>   include/linux/signal.h:147:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   _SIG_SET_BINOP(sigorsets, _sig_or)
>>   ^
>>   include/linux/signal.h:133:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 2:                                                         \
>>           ^
>>   include/linux/signal.h:147:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 1:                                                         \
>>           ^
>>   include/linux/signal.h:150:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   _SIG_SET_BINOP(sigandsets, _sig_and)
>>   ^
>>   include/linux/signal.h:133:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 2:                                                         \
>>           ^
>>   include/linux/signal.h:150:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 1:                                                         \
>>           ^
>>   include/linux/signal.h:153:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   _SIG_SET_BINOP(sigandnsets, _sig_andn)
>>   ^
>>   include/linux/signal.h:133:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 2:                                                         \
>>           ^
>>   include/linux/signal.h:153:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   include/linux/signal.h:137:2: note: expanded from macro '_SIG_SET_BINOP'
>>           case 1:                                                         \
>>           ^
>>   include/linux/signal.h:177:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   _SIG_SET_OP(signotset, _sig_not)
>>   ^
>>   include/linux/signal.h:167:2: note: expanded from macro '_SIG_SET_OP'
>>           case 2: set->sig[1] = op(set->sig[1]);                          \
>>           ^
>>   include/linux/signal.h:177:1: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>   include/linux/signal.h:169:2: note: expanded from macro '_SIG_SET_OP'
>>           case 1: set->sig[0] = op(set->sig[0]);                          \
>>           ^
>>   include/linux/signal.h:190:2: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>           case 1: set->sig[0] = 0;
>>           ^
>>   include/linux/signal.h:190:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>           case 1: set->sig[0] = 0;
>>           ^
>>           __attribute__((fallthrough));
>>   include/linux/signal.h:190:2: note: insert 'break;' to avoid fall-through
>>           case 1: set->sig[0] = 0;
>>           ^
>>           break;
>>   include/linux/signal.h:203:2: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>           case 1: set->sig[0] = -1;
>>           ^
>>   include/linux/signal.h:203:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>           case 1: set->sig[0] = -1;
>>           ^
>>           __attribute__((fallthrough));
>>   include/linux/signal.h:203:2: note: insert 'break;' to avoid fall-through
>>           case 1: set->sig[0] = -1;
>>           ^
>>           break;
>>   include/linux/signal.h:233:2: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>           case 1: ;
>>           ^
>>   include/linux/signal.h:233:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>           case 1: ;
>>           ^
>>           __attribute__((fallthrough));
>>   include/linux/signal.h:233:2: note: insert 'break;' to avoid fall-through
>>           case 1: ;
>>           ^
>>           break;
>>   include/linux/signal.h:245:2: warning: unannotated fall-through between
>switch labels [-Wimplicit-fallthrough]
>>           case 1: ;
>>           ^
>>   include/linux/signal.h:245:2: note: insert '__attribute__((fallthrough));' to
>silence this warning
>>           case 1: ;
>>           ^
>>           __attribute__((fallthrough));
>>   include/linux/signal.h:245:2: note: insert 'break;' to avoid fall-through
>>           case 1: ;
>>           ^
>>           break;
>>   In file included from kernel/printk/printk.c:61:
>>   kernel/printk/internal.h:54:20: warning: no previous prototype for function
>'vprintk_func' [-Wmissing-prototypes]
>>   __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
>>                      ^
>>   kernel/printk/internal.h:54:16: note: declare 'static' if the function is not
>intended to be used outside of this translation unit
>>   __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
>>                  ^
>>                  static
>>>> kernel/printk/printk.c:165:5: warning: no previous prototype for
>>>> function 'devkmsg_sysctl_set_loglvl' [-Wmissing-prototypes]
>>   int devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write,
>>       ^
>>   kernel/printk/printk.c:165:1: note: declare 'static' if the function is not
>intended to be used outside of this translation unit
>>   int devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write,
>>   ^
>>   static
>>   kernel/printk/printk.c:2406:10: warning: 'sprintf' will always overflow;
>destination buffer has size 0, but format string expands to at least 33 [-Wfortify-
>source]
>>                           len = sprintf(text,
>>                                 ^
>>   18 warnings generated.
>>
>>---
>>0-DAY CI Kernel Test Service, Intel Corporation
>>https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>
>
>
>--
>Wei Yang
>Help you, Help me