Commit 69b54314 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kbuild-fixes-v6.14' of... 

Merge tag 'kbuild-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Suppress false-positive -Wformat-{overflow,truncation}-non-kprintf
   warnings regardless of the W= option

 - Avoid CONFIG_TRIM_UNUSED_KSYMS dropping symbols passed to symbol_get()

 - Fix a build regression of the Debian linux-headers package

* tag 'kbuild-fixes-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: install-extmod-build: add missing quotation marks for CC variable
  kbuild: fix misspelling in scripts/Makefile.lib
  kbuild: keep symbols for symbol_get() even with CONFIG_TRIM_UNUSED_KSYMS
  scripts/Makefile.extrawarn: Do not show clang's non-kprintf warnings at W=1
parents 146339dd f354fc88

include/asm-generic/vmlinux.lds.h

+1 −0
Original line number Diff line number Diff line
@@ -1038,6 +1038,7 @@ defined(CONFIG_AUTOFDO_CLANG) || defined(CONFIG_PROPELLER_CLANG) 
	*(.discard)							\

	*(.discard.*)							\

	*(.export_symbol)						\

	*(.no_trim_symbol)						\

	*(.modinfo)							\

	/* ld.bfd warns about .gnu.version* even when not emitted */	\

	*(.gnu.version*)						\

include/linux/module.h

+4 −1
Original line number Diff line number Diff line
@@ -306,7 +306,10 @@ extern int modules_disabled; /* for sysctl */ 
/* Get/put a kernel symbol (calls must be symmetric) */

void *__symbol_get(const char *symbol);

void *__symbol_get_gpl(const char *symbol);

#define symbol_get(x) ((typeof(&x))(__symbol_get(__stringify(x))))

#define symbol_get(x)	({ \

	static const char __notrim[] \

		__used __section(".no_trim_symbol") = __stringify(x); \

	(typeof(&x))(__symbol_get(__stringify(x))); })



/* modules using other modules: kdb wants to see this. */

struct module_use {

scripts/Makefile.extrawarn

+5 −5
Original line number Diff line number Diff line
@@ -31,6 +31,11 @@ KBUILD_CFLAGS-$(CONFIG_CC_NO_ARRAY_BOUNDS) += -Wno-array-bounds 
ifdef CONFIG_CC_IS_CLANG

# The kernel builds with '-std=gnu11' so use of GNU extensions is acceptable.

KBUILD_CFLAGS += -Wno-gnu



# Clang checks for overflow/truncation with '%p', while GCC does not:

# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111219

KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow-non-kprintf)

KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation-non-kprintf)

else



# gcc inanely warns about local variables called 'main'
@@ -105,11 +110,6 @@ KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned) 
KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)

ifdef CONFIG_CC_IS_GCC

KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)

else

# Clang checks for overflow/truncation with '%p', while GCC does not:

# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111219

KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow-non-kprintf)

KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation-non-kprintf)

endif

KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)

scripts/Makefile.lib

+1 −1
Original line number Diff line number Diff line
@@ -305,7 +305,7 @@ endef 
# These are shared by some Makefile.* files.



ifdef CONFIG_LTO_CLANG

# Run $(LD) here to covert LLVM IR to ELF in the following cases:

# Run $(LD) here to convert LLVM IR to ELF in the following cases:

#  - when this object needs objtool processing, as objtool cannot process LLVM IR

#  - when this is a single-object module, as modpost cannot process LLVM IR

cmd_ld_single = $(if $(objtool-enabled)$(is-single-obj-m), ; $(LD) $(ld_flags) -r -o $(tmp-target) $@; mv $(tmp-target) $@)

scripts/mod/modpost.c

+35 −0
Original line number Diff line number Diff line
@@ -507,6 +507,9 @@ static int parse_elf(struct elf_info *info, const char *filename) 
			info->modinfo_len = sechdrs[i].sh_size;

		} else if (!strcmp(secname, ".export_symbol")) {

			info->export_symbol_secndx = i;

		} else if (!strcmp(secname, ".no_trim_symbol")) {

			info->no_trim_symbol = (void *)hdr + sechdrs[i].sh_offset;

			info->no_trim_symbol_len = sechdrs[i].sh_size;

		}



		if (sechdrs[i].sh_type == SHT_SYMTAB) {
@@ -1566,6 +1569,14 @@ static void read_symbols(const char *modname) 
	/* strip trailing .o */

	mod = new_module(modname, strlen(modname) - strlen(".o"));



	/* save .no_trim_symbol section for later use */

	if (info.no_trim_symbol_len) {

		mod->no_trim_symbol = xmalloc(info.no_trim_symbol_len);

		memcpy(mod->no_trim_symbol, info.no_trim_symbol,

		       info.no_trim_symbol_len);

		mod->no_trim_symbol_len = info.no_trim_symbol_len;

	}



	if (!mod->is_vmlinux) {

		license = get_modinfo(&info, "license");

		if (!license)
@@ -1728,6 +1739,28 @@ static void handle_white_list_exports(const char *white_list) 
	free(buf);

}



/*

 * Keep symbols recorded in the .no_trim_symbol section. This is necessary to

 * prevent CONFIG_TRIM_UNUSED_KSYMS from dropping EXPORT_SYMBOL because

 * symbol_get() relies on the symbol being present in the ksymtab for lookups.

 */

static void keep_no_trim_symbols(struct module *mod)

{

	unsigned long size = mod->no_trim_symbol_len;



	for (char *s = mod->no_trim_symbol; s; s = next_string(s , &size)) {

		struct symbol *sym;



		/*

		 * If find_symbol() returns NULL, this symbol is not provided

		 * by any module, and symbol_get() will fail.

		 */

		sym = find_symbol(s);

		if (sym)

			sym->used = true;

	}

}



static void check_modname_len(struct module *mod)

{

	const char *mod_name;
@@ -2254,6 +2287,8 @@ int main(int argc, char **argv) 
		read_symbols_from_files(files_source);



	list_for_each_entry(mod, &modules, list) {

		keep_no_trim_symbols(mod);



		if (mod->dump_file || mod->is_vmlinux)

			continue;