| Message ID | 20190924120740.12425-1-yamada.masahiro@socionext.com |
|---|---|
| State | Accepted |
| Commit | 47346e96f004eca07720e1e2b24fc7f0b0df4092 |
| Headers | show |
| Series | modpost: fix static EXPORT_SYMBOL warnings for UML build | expand |
On Tue, 2019-09-24 at 21:07 +0900, Masahiro Yamada wrote: > Johannes Berg reports lots of modpost warnings on ARCH=um builds: > > WARNING: "rename" [vmlinux] is a static EXPORT_SYMBOL > [snip] > WARNING: "__stack_smash_handler" [vmlinux] is a static EXPORT_SYMBOL > > When you run "make", the modpost is run twice; before linking vmlinux, > and before building modules. All the warnings above are from the second > modpost. > > The offending symbols are defined not in vmlinux, but in the C library. > The first modpost is run against the relocatable vmlinux.o, and those > warnings are nicely suppressed because the SH_UNDEF entries from the > symbol table clear the ->is_static flag. > > The second modpost is run against the executable vmlinux (+ modules), > where those symbols have been resolved, but the definitions do not > exist. > > This commit fixes it in a straight forward way. Suppress the static > EXPORT_SYMBOL warnings from "vmlinux". Yep, that fixes it. Tested-by: Johannes Berg <johannes@sipsolutions.net> Thanks! johannes
Hi, On 24.09.2019 15:07, Masahiro Yamada wrote: > Johannes Berg reports lots of modpost warnings on ARCH=um builds: > > WARNING: "rename" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "lseek" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "ftruncate64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "getuid" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "lseek64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "unlink" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "pwrite64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "close" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "opendir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "pread64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "syscall" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "readdir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "readdir64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "futimes" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__lxstat" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "write" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "closedir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__xstat" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "fsync" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__lxstat64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__fxstat64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "telldir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "printf" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "readlink" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__sprintf_chk" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "link" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "rmdir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "fdatasync" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "truncate" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "statfs" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__errno_location" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__xmknod" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "open64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "truncate64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "open" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "read" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "chown" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "chmod" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "utime" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "fchmod" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "seekdir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "ioctl" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "dup2" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "statfs64" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "utimes" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "mkdir" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "fchown" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__guard" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "symlink" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "access" [vmlinux] is a static EXPORT_SYMBOL > WARNING: "__stack_smash_handler" [vmlinux] is a static EXPORT_SYMBOL > > When you run "make", the modpost is run twice; before linking vmlinux, > and before building modules. All the warnings above are from the second > modpost. > > The offending symbols are defined not in vmlinux, but in the C library. > The first modpost is run against the relocatable vmlinux.o, and those > warnings are nicely suppressed because the SH_UNDEF entries from the > symbol table clear the ->is_static flag. > > The second modpost is run against the executable vmlinux (+ modules), > where those symbols have been resolved, but the definitions do not > exist. > > This commit fixes it in a straight forward way. Suppress the static > EXPORT_SYMBOL warnings from "vmlinux". > > We see the same warnings twice anyway. For example, ARCH=arm64 defconfig > shows the following warning twice: > > WARNING: "HYPERVISOR_platform_op" [vmlinux] is a static EXPORT_SYMBOL_GPL > > So, it is reasonable to suppress the second one. Thanks, for fixing it. You can add my if you need Tested-by: Denis Efremov <efremov@linux.com> Tested on x86_64 and um arches. I've reverted the commit b08918fb3f2 "lz4: do not export static symbol" and checked for the warning. On um arch I've tested that this fixes the false-positives. > > Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") > Reported-by: Johannes Berg <johannes@sipsolutions.net> > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > scripts/mod/modpost.c | 13 +++++++++---- > 1 file changed, 9 insertions(+), 4 deletions(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 3961941e8e7a..442d5e2ad688 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -2652,15 +2652,20 @@ int main(int argc, char **argv) > fatal("modpost: Section mismatches detected.\n" > "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n"); > for (n = 0; n < SYMBOL_HASH_SIZE; n++) { > - struct symbol *s = symbolhash[n]; > + struct symbol *s; > + > + for (s = symbolhash[n]; s; s = s->next) { > + /* > + * Do not check "vmlinux". This avoids the same warnings > + * shown twice, and false-positives for ARCH=um. > + */ > + if (is_vmlinux(s->module->name) && !s->module->is_dot_o) > + continue; > > - while (s) { > if (s->is_static) > warn("\"%s\" [%s] is a static %s\n", > s->name, s->module->name, > export_str(s->export)); > - > - s = s->next; > } > } > >
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 3961941e8e7a..442d5e2ad688 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2652,15 +2652,20 @@ int main(int argc, char **argv) fatal("modpost: Section mismatches detected.\n" "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n"); for (n = 0; n < SYMBOL_HASH_SIZE; n++) { - struct symbol *s = symbolhash[n]; + struct symbol *s; + + for (s = symbolhash[n]; s; s = s->next) { + /* + * Do not check "vmlinux". This avoids the same warnings + * shown twice, and false-positives for ARCH=um. + */ + if (is_vmlinux(s->module->name) && !s->module->is_dot_o) + continue; - while (s) { if (s->is_static) warn("\"%s\" [%s] is a static %s\n", s->name, s->module->name, export_str(s->export)); - - s = s->next; } }
Johannes Berg reports lots of modpost warnings on ARCH=um builds: WARNING: "rename" [vmlinux] is a static EXPORT_SYMBOL WARNING: "lseek" [vmlinux] is a static EXPORT_SYMBOL WARNING: "ftruncate64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "getuid" [vmlinux] is a static EXPORT_SYMBOL WARNING: "lseek64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "unlink" [vmlinux] is a static EXPORT_SYMBOL WARNING: "pwrite64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "close" [vmlinux] is a static EXPORT_SYMBOL WARNING: "opendir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "pread64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "syscall" [vmlinux] is a static EXPORT_SYMBOL WARNING: "readdir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "readdir64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "futimes" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__lxstat" [vmlinux] is a static EXPORT_SYMBOL WARNING: "write" [vmlinux] is a static EXPORT_SYMBOL WARNING: "closedir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__xstat" [vmlinux] is a static EXPORT_SYMBOL WARNING: "fsync" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__lxstat64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__fxstat64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "telldir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "printf" [vmlinux] is a static EXPORT_SYMBOL WARNING: "readlink" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__sprintf_chk" [vmlinux] is a static EXPORT_SYMBOL WARNING: "link" [vmlinux] is a static EXPORT_SYMBOL WARNING: "rmdir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "fdatasync" [vmlinux] is a static EXPORT_SYMBOL WARNING: "truncate" [vmlinux] is a static EXPORT_SYMBOL WARNING: "statfs" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__errno_location" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__xmknod" [vmlinux] is a static EXPORT_SYMBOL WARNING: "open64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "truncate64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "open" [vmlinux] is a static EXPORT_SYMBOL WARNING: "read" [vmlinux] is a static EXPORT_SYMBOL WARNING: "chown" [vmlinux] is a static EXPORT_SYMBOL WARNING: "chmod" [vmlinux] is a static EXPORT_SYMBOL WARNING: "utime" [vmlinux] is a static EXPORT_SYMBOL WARNING: "fchmod" [vmlinux] is a static EXPORT_SYMBOL WARNING: "seekdir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "ioctl" [vmlinux] is a static EXPORT_SYMBOL WARNING: "dup2" [vmlinux] is a static EXPORT_SYMBOL WARNING: "statfs64" [vmlinux] is a static EXPORT_SYMBOL WARNING: "utimes" [vmlinux] is a static EXPORT_SYMBOL WARNING: "mkdir" [vmlinux] is a static EXPORT_SYMBOL WARNING: "fchown" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__guard" [vmlinux] is a static EXPORT_SYMBOL WARNING: "symlink" [vmlinux] is a static EXPORT_SYMBOL WARNING: "access" [vmlinux] is a static EXPORT_SYMBOL WARNING: "__stack_smash_handler" [vmlinux] is a static EXPORT_SYMBOL When you run "make", the modpost is run twice; before linking vmlinux, and before building modules. All the warnings above are from the second modpost. The offending symbols are defined not in vmlinux, but in the C library. The first modpost is run against the relocatable vmlinux.o, and those warnings are nicely suppressed because the SH_UNDEF entries from the symbol table clear the ->is_static flag. The second modpost is run against the executable vmlinux (+ modules), where those symbols have been resolved, but the definitions do not exist. This commit fixes it in a straight forward way. Suppress the static EXPORT_SYMBOL warnings from "vmlinux". We see the same warnings twice anyway. For example, ARCH=arm64 defconfig shows the following warning twice: WARNING: "HYPERVISOR_platform_op" [vmlinux] is a static EXPORT_SYMBOL_GPL So, it is reasonable to suppress the second one. Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") Reported-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- scripts/mod/modpost.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) -- 2.17.1