| Message ID | 20220501084032.1025918-3-masahiroy@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kbuild: yet another series of cleanups (modpost and LTO) | expand |
On Sun, May 1, 2022 at 1:42 AM Masahiro Yamada <masahiroy@kernel.org> wrote: > > Currently, mod->gpl_compatible is tristate; it is set to -1 by default, > then to 1 or 0 when MODULE_LICENSE() is found. > > Maybe, -1 was chosen to represent the 'unknown' license, but it is not > useful. > > The current code: > > if (!mod->gpl_compatible) > check_for_gpl_usage(exp->export, basename, exp->name); > > ... only cares whether gpl_compatible is zero or not. > > Change it to a bool type with the initial value 'true', which has no > functional change. > > The default value should be 'true' instead of 'false'. > > Since commit 1d6cd3929360 ("modpost: turn missing MODULE_LICENSE() into > error"), unknown module license is an error. > > The error message, "missing MODULE_LICENSE()" is enough to explain the > issue. It is not sensible to show another message, "GPL-incompatible > module ... uses GPL-only symbol". > > Add comments to explain this. > > While I was here, I renamed gpl_compatible to is_gpl_compatible for > clarification, and also slightly refactored the code. > > Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Thanks for the patch! Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index a6035ab78cd8..f2d6c152cd3f 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -187,7 +187,14 @@ static struct module *new_module(const char *modname) /* add to list */ strcpy(mod->name, modname); mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0); - mod->gpl_compatible = -1; + + /* + * Set mod->is_gpl_compatible to true by default to skip + * check_for_gpl_usage() when MODULE_LICENSE() is missing. + * If it is the case, modpost will exit with error anyway. + */ + mod->is_gpl_compatible = true; + mod->next = modules; modules = mod; @@ -2012,10 +2019,8 @@ static void read_symbols(const char *modname) if (!license) error("missing MODULE_LICENSE() in %s\n", modname); while (license) { - if (license_is_gpl_compatible(license)) - mod->gpl_compatible = 1; - else { - mod->gpl_compatible = 0; + if (!license_is_gpl_compatible(license)) { + mod->is_gpl_compatible = false; break; } license = get_next_modinfo(&info, "license", license); @@ -2183,7 +2188,7 @@ static void check_exports(struct module *mod) add_namespace(&mod->missing_namespaces, exp->namespace); } - if (!mod->gpl_compatible) + if (!mod->is_gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); } } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 7ccfcc8899c1..f21a3782885b 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -110,7 +110,7 @@ buf_write(struct buffer *buf, const char *s, int len); struct module { struct module *next; - int gpl_compatible; + bool is_gpl_compatible; struct symbol *unres; bool from_dump; /* true if module was loaded from *.symvers */ bool is_vmlinux;
Currently, mod->gpl_compatible is tristate; it is set to -1 by default, then to 1 or 0 when MODULE_LICENSE() is found. Maybe, -1 was chosen to represent the 'unknown' license, but it is not useful. The current code: if (!mod->gpl_compatible) check_for_gpl_usage(exp->export, basename, exp->name); ... only cares whether gpl_compatible is zero or not. Change it to a bool type with the initial value 'true', which has no functional change. The default value should be 'true' instead of 'false'. Since commit 1d6cd3929360 ("modpost: turn missing MODULE_LICENSE() into error"), unknown module license is an error. The error message, "missing MODULE_LICENSE()" is enough to explain the issue. It is not sensible to show another message, "GPL-incompatible module ... uses GPL-only symbol". Add comments to explain this. While I was here, I renamed gpl_compatible to is_gpl_compatible for clarification, and also slightly refactored the code. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> --- Changes in v2: - Split as a separate commit - More code refactoring - Add a comment - Rename it to ->is_gpl_compatible (Nick) scripts/mod/modpost.c | 17 +++++++++++------ scripts/mod/modpost.h | 2 +- 2 files changed, 12 insertions(+), 7 deletions(-)