powerpc/module_64: use module_init_section instead of patching names

Without this patch, module init sections are disabled by patching their
names in arch-specific code when they're loaded (which prevents code in
layout_sections from finding init sections). This patch uses the new
arch-specific module_init_section instead.

This allows modules that have .init_array sections to have the
initialisers properly called (on load, before init). Without this patch,
the initialisers are not called because .init_array is renamed to
_init_array, and thus isn't found by code in find_module_sections().
Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220202055123.2144842-1-wedsonaf@google.com

arch/powerpc/kernel/module_64.c

@@ -277,6 +277,12 @@ static Elf64_Sym *find_dot_toc(Elf64_Shdr *sechdrs,
 	return NULL;
 }
 
+bool module_init_section(const char *name)
+{
+	/* We don't handle .init for the moment: always return false. */
+	return false;
+}
+
 int module_frob_arch_sections(Elf64_Ehdr *hdr,
 			      Elf64_Shdr *sechdrs,
 			      char *secstrings,
@@ -286,7 +292,6 @@ int module_frob_arch_sections(Elf64_Ehdr *hdr,
 
 	/* Find .toc and .stubs sections, symtab and strtab */
 	for (i = 1; i < hdr->e_shnum; i++) {
-		char *p;
 		if (strcmp(secstrings + sechdrs[i].sh_name, ".stubs") == 0)
 			me->arch.stubs_section = i;
 		else if (strcmp(secstrings + sechdrs[i].sh_name, ".toc") == 0) {
@@ -298,10 +303,6 @@ int module_frob_arch_sections(Elf64_Ehdr *hdr,
 			dedotify_versions((void *)hdr + sechdrs[i].sh_offset,
 					  sechdrs[i].sh_size);
 
-		/* We don't handle .init for the moment: rename to _init */
-		while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init")))
-			p[0] = '_';
-
 		if (sechdrs[i].sh_type == SHT_SYMTAB)
 			dedotify((void *)hdr + sechdrs[i].sh_offset,
 				 sechdrs[i].sh_size / sizeof(Elf64_Sym),