| Message ID | 20190906151059.1077708-1-arnd@arndb.de |
|---|---|
| State | New |
| Headers | show |
| Series | mostpost: don't warn about symbols from another file | expand |
Hi, On 06.09.2019 18:10, Arnd Bergmann wrote: > On architectures such as ARM that have a list of symbols exported from > assembler in a separate C file, we get a lot of new warnings: > > WARNING: "__ashrdi3" [vmlinux] is a static (unknown) > WARNING: "__lshrdi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) > WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) > WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) > WARNING: "__udivsi3" [vmlinux] is a static (unknown) > WARNING: "_change_bit" [vmlinux] is a static (unknown) > WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) > WARNING: "__umodsi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) > WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) > WARNING: "__muldi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) > WARNING: "__raw_writesb" [vmlinux] is a static (unknown) > WARNING: "__raw_readsb" [vmlinux] is a static (unknown) > ... > > This is not helpful, as these are clearly not static symbols > at all. Suppress the warning in a case like this. > It looks very similar to this discussion https://lkml.org/lkml/2019/7/30/112 Could you please write the steps to reproduce the warnings? Now, I'm trying to build linux-next (host Ubuntu 19.04 x86_64) with: $ make ARCH=arm CROSS_COMPILE=/usr/bin/arm-linux-gnueabi- But I can't get these warnings. I would like to check the type of this asm symbols. It seems like they are STT_NOTYPE. In this case the fix could also involve ELF_ST_TYPE check. Thanks, Denis > Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > scripts/mod/modpost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 76c221dd9b2b..4265dd924933 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -2543,7 +2543,7 @@ int main(int argc, char **argv) > struct symbol *s = symbolhash[n]; > > while (s) { > - if (s->is_static) > + if (s->is_static && s->export != export_unknown) > warn("\"%s\" [%s] is a static %s\n", > s->name, s->module->name, > export_str(s->export)); >
On 07.09.2019 01:39, Denis Efremov wrote: > Hi, > > On 06.09.2019 18:10, Arnd Bergmann wrote: >> On architectures such as ARM that have a list of symbols exported from >> assembler in a separate C file, we get a lot of new warnings: >> >> WARNING: "__ashrdi3" [vmlinux] is a static (unknown) >> WARNING: "__lshrdi3" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) >> WARNING: "__udivsi3" [vmlinux] is a static (unknown) >> WARNING: "_change_bit" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) >> WARNING: "__umodsi3" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) >> WARNING: "__muldi3" [vmlinux] is a static (unknown) >> WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) >> WARNING: "__raw_writesb" [vmlinux] is a static (unknown) >> WARNING: "__raw_readsb" [vmlinux] is a static (unknown) >> ... >> >> This is not helpful, as these are clearly not static symbols >> at all. Suppress the warning in a case like this. >> > > It looks very similar to this discussion https://lkml.org/lkml/2019/7/30/112 > > Could you please write the steps to reproduce the warnings? > Now, I'm trying to build linux-next (host Ubuntu 19.04 x86_64) with: > $ make ARCH=arm CROSS_COMPILE=/usr/bin/arm-linux-gnueabi- > But I can't get these warnings. Tried defconfig, allyesconfig. > > I would like to check the type of this asm symbols. It seems like they > are STT_NOTYPE. In this case the fix could also involve ELF_ST_TYPE check. > Ah, I forgot that we don't check the type at all, so this is not the case. But still, I would like to test what if the remove binding check at all? diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 76c221dd9b2b..97dbcebf2338 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1987,14 +1987,12 @@ static void read_symbols(const char *modname) for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { unsigned char bind = ELF_ST_BIND(sym->st_info); - if (bind == STB_GLOBAL || bind == STB_WEAK) { struct symbol *s = find_symbol(remove_dot(info.strtab + sym->st_name)); if (s) s->is_static = 0; - } } if (!is_vmlinux(modname) || vmlinux_section_warnings) Thanks, Denis > >> Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") >> Signed-off-by: Arnd Bergmann <arnd@arndb.de> >> --- >> scripts/mod/modpost.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c >> index 76c221dd9b2b..4265dd924933 100644 >> --- a/scripts/mod/modpost.c >> +++ b/scripts/mod/modpost.c >> @@ -2543,7 +2543,7 @@ int main(int argc, char **argv) >> struct symbol *s = symbolhash[n]; >> >> while (s) { >> - if (s->is_static) >> + if (s->is_static && s->export != export_unknown) >> warn("\"%s\" [%s] is a static %s\n", >> s->name, s->module->name, >> export_str(s->export)); >>
On Sat, Sep 7, 2019 at 7:28 AM Denis Efremov <efremov@linux.com> wrote: > On 07.09.2019 01:39, Denis Efremov wrote: > >> This is not helpful, as these are clearly not static symbols > >> at all. Suppress the warning in a case like this. > >> > > > > It looks very similar to this discussion https://lkml.org/lkml/2019/7/30/112 > > > > Could you please write the steps to reproduce the warnings? > > > Now, I'm trying to build linux-next (host Ubuntu 19.04 x86_64) with: > > $ make ARCH=arm CROSS_COMPILE=/usr/bin/arm-linux-gnueabi- > > But I can't get these warnings. > > Tried defconfig, allyesconfig. I only have one randconfig build that caused these, see http://paste.ubuntu.com/p/D6w8RNS7MG/ for the .config I was building linux-next with the clang-9 toolchain from http://apt.llvm.org, but that should not matter here. > > I would like to check the type of this asm symbols. It seems like they > > are STT_NOTYPE. In this case the fix could also involve ELF_ST_TYPE check. > > > > Ah, I forgot that we don't check the type at all, so this is not the case. > But still, I would like to test what if the remove binding check at all? > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 76c221dd9b2b..97dbcebf2338 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -1987,14 +1987,12 @@ static void read_symbols(const char *modname) > for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { > unsigned char bind = ELF_ST_BIND(sym->st_info); > > - if (bind == STB_GLOBAL || bind == STB_WEAK) { > struct symbol *s = > find_symbol(remove_dot(info.strtab + > sym->st_name)); > > if (s) > s->is_static = 0; > - } > } > > if (!is_vmlinux(modname) || vmlinux_section_warnings) Unfortunately, I still get the same warnings, plus one about modpost.c: scripts/mod/modpost.c:1988:17: warning: unused variable ‘bind’ [-Wunused-variable] WARNING: "__ashrdi3" [vmlinux] is a static (unknown) WARNING: "__lshrdi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) WARNING: "__udivsi3" [vmlinux] is a static (unknown) WARNING: "_change_bit" [vmlinux] is a static (unknown) WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) WARNING: "__umodsi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) WARNING: "__muldi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) WARNING: "__raw_writesb" [vmlinux] is a static (unknown) WARNING: "__raw_readsb" [vmlinux] is a static (unknown) WARNING: "__ucmpdi2" [vmlinux] is a static (unknown) WARNING: "__aeabi_lmul" [vmlinux] is a static (unknown) WARNING: "__divsi3" [vmlinux] is a static (unknown) WARNING: "__modsi3" [vmlinux] is a static (unknown) WARNING: "_test_and_change_bit" [vmlinux] is a static (unknown) WARNING: "__bswapdi2" [vmlinux] is a static (unknown) WARNING: "__bswapsi2" [vmlinux] is a static (unknown) WARNING: "__ashldi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsl" [vmlinux] is a static (unknown) WARNING: "__ashrdi3" [vmlinux] is a static (unknown) WARNING: "__lshrdi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) WARNING: "__udivsi3" [vmlinux] is a static (unknown) WARNING: "_change_bit" [vmlinux] is a static (unknown) WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) WARNING: "__umodsi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) WARNING: "__muldi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) WARNING: "__raw_writesb" [vmlinux] is a static (unknown) WARNING: "__raw_readsb" [vmlinux] is a static (unknown) WARNING: "__ucmpdi2" [vmlinux] is a static (unknown) WARNING: "__aeabi_lmul" [vmlinux] is a static (unknown) WARNING: "__divsi3" [vmlinux] is a static (unknown) WARNING: "__modsi3" [vmlinux] is a static (unknown) WARNING: "_test_and_change_bit" [vmlinux] is a static (unknown) WARNING: "__bswapdi2" [vmlinux] is a static (unknown) WARNING: "__bswapsi2" [vmlinux] is a static (unknown) WARNING: "__ashldi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsl" [vmlinux] is a static (unknown) Arnd
On 06.09.2019 18:10, Arnd Bergmann wrote: > On architectures such as ARM that have a list of symbols exported > from assembler in a separate C file, we get a lot of new warnings: > > WARNING: "__ashrdi3" [vmlinux] is a static (unknown) WARNING: > "__lshrdi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsr" > [vmlinux] is a static (unknown) WARNING: "__aeabi_lasr" [vmlinux] is > a static (unknown) WARNING: "__aeabi_uidivmod" [vmlinux] is a static > (unknown) WARNING: "__udivsi3" [vmlinux] is a static (unknown) > WARNING: "_change_bit" [vmlinux] is a static (unknown) WARNING: > "__aeabi_idiv" [vmlinux] is a static (unknown) WARNING: "__umodsi3" > [vmlinux] is a static (unknown) WARNING: "__aeabi_uidiv" [vmlinux] is > a static (unknown) WARNING: "__aeabi_idivmod" [vmlinux] is a static > (unknown) WARNING: "__muldi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) WARNING: > "__raw_writesb" [vmlinux] is a static (unknown) WARNING: > "__raw_readsb" [vmlinux] is a static (unknown) ... > > This is not helpful, as these are clearly not static symbols at all. > Suppress the warning in a case like this. > > Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* > functions") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Tested-by: Denis Efremov <efremov@linux.com> What I could add here is that all these symbols are: $ nm vmlinux | grep '__ashrdi3\|__lshrdi3\|__aeabi_llsr\|...' cd63c845 A __crc___aeabi_lasr 76cf47f6 A __crc___aeabi_llsl 8a4fa83b A __crc___aeabi_llsr 44643b93 A __crc___aeabi_lmul f564412a A __crc___aeabi_ulcmp 40f07981 A __crc___ashldi3 edd9106d A __crc___ashrdi3 389ecf9e A __crc___bswapdi2 f1ea6f1c A __crc___bswapsi2 14d4a9c5 A __crc__change_bit ff67b37f A __crc___lshrdi3 800e4ffa A __crc___muldi3 f7163ec9 A __crc___raw_readsb f0ed2ef4 A __crc___raw_writesb ffb94ef0 A __crc__test_and_change_bit 7cc035a7 A __crc___ucmpdi2 There is no ksymtab, kstrtab for them and there is no the exact symbols, only crc. Thus they get to the symbolhash table from handle_modversions() -> sym_update_crc(). Since there is no the exact symbols, e.g. like nm vmlinux | grep __kmalloc 2d6fcc06 A __crc___kmalloc c01c922d T __kmalloc <--- c0749192 r __kstrtab___kmalloc c073c7c4 r __ksymtab___kmalloc we can't check them in this cycle: // check for static EXPORT_SYMBOL_* functions && global vars for (sym = info.symtab_start; sym < info.symtab_stop; sym++) { and they are automatically marked as static. That's all so far, I don't know is it correct to have only __crc* or not for a symbol. Just a sidenote: arch/arm/kernel/armksyms.c states that these are /* * libgcc functions - functions that are used internally by the * compiler... Thanks, Denis > --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 > deletion(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index > 76c221dd9b2b..4265dd924933 100644 --- a/scripts/mod/modpost.c +++ > b/scripts/mod/modpost.c @@ -2543,7 +2543,7 @@ int main(int argc, char > **argv) struct symbol *s = symbolhash[n]; > > while (s) { - if (s->is_static) + if (s->is_static && s->export > != export_unknown) warn("\"%s\" [%s] is a static %s\n", s->name, > s->module->name, export_str(s->export)); >
On Sat, Sep 7, 2019 at 12:11 AM Arnd Bergmann <arnd@arndb.de> wrote: > > On architectures such as ARM that have a list of symbols exported from > assembler in a separate C file, we get a lot of new warnings: > > WARNING: "__ashrdi3" [vmlinux] is a static (unknown) > WARNING: "__lshrdi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) > WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) > WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) > WARNING: "__udivsi3" [vmlinux] is a static (unknown) > WARNING: "_change_bit" [vmlinux] is a static (unknown) > WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) > WARNING: "__umodsi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) > WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) > WARNING: "__muldi3" [vmlinux] is a static (unknown) > WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) > WARNING: "__raw_writesb" [vmlinux] is a static (unknown) > WARNING: "__raw_readsb" [vmlinux] is a static (unknown) > ... > > This is not helpful, as these are clearly not static symbols > at all. Suppress the warning in a case like this. > > Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> This patch is not root-causing the problem, rather it is hiding it. I posted a real fix: https://patchwork.kernel.org/patch/11137689/ > --- > scripts/mod/modpost.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c > index 76c221dd9b2b..4265dd924933 100644 > --- a/scripts/mod/modpost.c > +++ b/scripts/mod/modpost.c > @@ -2543,7 +2543,7 @@ int main(int argc, char **argv) > struct symbol *s = symbolhash[n]; > > while (s) { > - if (s->is_static) > + if (s->is_static && s->export != export_unknown) > warn("\"%s\" [%s] is a static %s\n", > s->name, s->module->name, > export_str(s->export)); > -- > 2.20.0 > -- Best Regards Masahiro Yamada
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 76c221dd9b2b..4265dd924933 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -2543,7 +2543,7 @@ int main(int argc, char **argv) struct symbol *s = symbolhash[n]; while (s) { - if (s->is_static) + if (s->is_static && s->export != export_unknown) warn("\"%s\" [%s] is a static %s\n", s->name, s->module->name, export_str(s->export));
On architectures such as ARM that have a list of symbols exported from assembler in a separate C file, we get a lot of new warnings: WARNING: "__ashrdi3" [vmlinux] is a static (unknown) WARNING: "__lshrdi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_llsr" [vmlinux] is a static (unknown) WARNING: "__aeabi_lasr" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidivmod" [vmlinux] is a static (unknown) WARNING: "__udivsi3" [vmlinux] is a static (unknown) WARNING: "_change_bit" [vmlinux] is a static (unknown) WARNING: "__aeabi_idiv" [vmlinux] is a static (unknown) WARNING: "__umodsi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_uidiv" [vmlinux] is a static (unknown) WARNING: "__aeabi_idivmod" [vmlinux] is a static (unknown) WARNING: "__muldi3" [vmlinux] is a static (unknown) WARNING: "__aeabi_ulcmp" [vmlinux] is a static (unknown) WARNING: "__raw_writesb" [vmlinux] is a static (unknown) WARNING: "__raw_readsb" [vmlinux] is a static (unknown) ... This is not helpful, as these are clearly not static symbols at all. Suppress the warning in a case like this. Fixes: 15bfc2348d54 ("modpost: check for static EXPORT_SYMBOL* functions") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) -- 2.20.0