1 /* Kernel module help for PPC64.
2 Copyright (C) 2001, 2003 Rusty Russell IBM Corporation.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
21 #include <linux/module.h>
22 #include <linux/elf.h>
23 #include <linux/moduleloader.h>
24 #include <linux/err.h>
25 #include <linux/vmalloc.h>
26 #include <linux/ftrace.h>
27 #include <linux/bug.h>
28 #include <linux/uaccess.h>
29 #include <asm/module.h>
30 #include <asm/firmware.h>
31 #include <asm/code-patching.h>
32 #include <linux/sort.h>
33 #include <asm/setup.h>
34 #include <asm/sections.h>
36 /* FIXME: We don't do .init separately. To do this, we'd need to have
37 a separate r2 value in the init and core section, and stub between
40 Using a magic allocator which places modules within 32MB solves
41 this, and makes other things simpler. Anton?
44 #ifdef PPC64_ELF_ABI_v2
46 /* An address is simply the address of the function. */
47 typedef unsigned long func_desc_t;
49 static func_desc_t func_desc(unsigned long addr)
53 static unsigned long func_addr(unsigned long addr)
57 static unsigned long stub_func_addr(func_desc_t func)
62 /* PowerPC64 specific values for the Elf64_Sym st_other field. */
63 #define STO_PPC64_LOCAL_BIT 5
64 #define STO_PPC64_LOCAL_MASK (7 << STO_PPC64_LOCAL_BIT)
65 #define PPC64_LOCAL_ENTRY_OFFSET(other) \
66 (((1 << (((other) & STO_PPC64_LOCAL_MASK) >> STO_PPC64_LOCAL_BIT)) >> 2) << 2)
68 static unsigned int local_entry_offset(const Elf64_Sym *sym)
70 /* sym->st_other indicates offset to local entry point
71 * (otherwise it will assume r12 is the address of the start
72 * of function and try to derive r2 from it). */
73 return PPC64_LOCAL_ENTRY_OFFSET(sym->st_other);
77 /* An address is address of the OPD entry, which contains address of fn. */
78 typedef struct ppc64_opd_entry func_desc_t;
80 static func_desc_t func_desc(unsigned long addr)
82 return *(struct ppc64_opd_entry *)addr;
84 static unsigned long func_addr(unsigned long addr)
86 return func_desc(addr).funcaddr;
88 static unsigned long stub_func_addr(func_desc_t func)
92 static unsigned int local_entry_offset(const Elf64_Sym *sym)
97 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
99 if (ptr < (void *)mod->arch.start_opd ||
100 ptr >= (void *)mod->arch.end_opd)
103 return dereference_function_descriptor(ptr);
107 #define STUB_MAGIC 0x73747562 /* stub */
109 /* Like PPC32, we need little trampolines to do > 24-bit jumps (into
110 the kernel itself). But on PPC64, these need to be used for every
111 jump, actually, to reset r2 (TOC+0x8000). */
112 struct ppc64_stub_entry
114 /* 28 byte jump instruction sequence (7 instructions). We only
115 * need 6 instructions on ABIv2 but we always allocate 7 so
116 * so we don't have to modify the trampoline load instruction. */
118 /* Used by ftrace to identify stubs */
120 /* Data for the above code */
121 func_desc_t funcdata;
125 * PPC64 uses 24 bit jumps, but we need to jump into other modules or
126 * the kernel which may be further. So we jump to a stub.
128 * For ELFv1 we need to use this to set up the new r2 value (aka TOC
129 * pointer). For ELFv2 it's the callee's responsibility to set up the
130 * new r2, but for both we need to save the old r2.
132 * We could simply patch the new r2 value and function pointer into
133 * the stub, but it's significantly shorter to put these values at the
134 * end of the stub code, and patch the stub address (32-bits relative
135 * to the TOC ptr, r2) into the stub.
138 static u32 ppc64_stub_insns[] = {
139 0x3d620000, /* addis r11,r2, <high> */
140 0x396b0000, /* addi r11,r11, <low> */
141 /* Save current r2 value in magic place on the stack. */
142 0xf8410000|R2_STACK_OFFSET, /* std r2,R2_STACK_OFFSET(r1) */
143 0xe98b0020, /* ld r12,32(r11) */
144 #ifdef PPC64_ELF_ABI_v1
145 /* Set up new r2 from function descriptor */
146 0xe84b0028, /* ld r2,40(r11) */
148 0x7d8903a6, /* mtctr r12 */
149 0x4e800420 /* bctr */
152 #ifdef CONFIG_DYNAMIC_FTRACE
153 int module_trampoline_target(struct module *mod, unsigned long addr,
154 unsigned long *target)
156 struct ppc64_stub_entry *stub;
157 func_desc_t funcdata;
160 if (!within_module_core(addr, mod)) {
161 pr_err("%s: stub %lx not in module %s\n", __func__, addr, mod->name);
165 stub = (struct ppc64_stub_entry *)addr;
167 if (probe_kernel_read(&magic, &stub->magic, sizeof(magic))) {
168 pr_err("%s: fault reading magic for stub %lx for %s\n", __func__, addr, mod->name);
172 if (magic != STUB_MAGIC) {
173 pr_err("%s: bad magic for stub %lx for %s\n", __func__, addr, mod->name);
177 if (probe_kernel_read(&funcdata, &stub->funcdata, sizeof(funcdata))) {
178 pr_err("%s: fault reading funcdata for stub %lx for %s\n", __func__, addr, mod->name);
182 *target = stub_func_addr(funcdata);
188 /* Count how many different 24-bit relocations (different symbol,
190 static unsigned int count_relocs(const Elf64_Rela *rela, unsigned int num)
192 unsigned int i, r_info, r_addend, _count_relocs;
194 /* FIXME: Only count external ones --RR */
198 for (i = 0; i < num; i++)
199 /* Only count 24-bit relocs, others don't need stubs */
200 if (ELF64_R_TYPE(rela[i].r_info) == R_PPC_REL24 &&
201 (r_info != ELF64_R_SYM(rela[i].r_info) ||
202 r_addend != rela[i].r_addend)) {
204 r_info = ELF64_R_SYM(rela[i].r_info);
205 r_addend = rela[i].r_addend;
208 return _count_relocs;
211 static int relacmp(const void *_x, const void *_y)
213 const Elf64_Rela *x, *y;
215 y = (Elf64_Rela *)_x;
216 x = (Elf64_Rela *)_y;
218 /* Compare the entire r_info (as opposed to ELF64_R_SYM(r_info) only) to
219 * make the comparison cheaper/faster. It won't affect the sorting or
220 * the counting algorithms' performance
222 if (x->r_info < y->r_info)
224 else if (x->r_info > y->r_info)
226 else if (x->r_addend < y->r_addend)
228 else if (x->r_addend > y->r_addend)
234 static void relaswap(void *_x, void *_y, int size)
236 uint64_t *x, *y, tmp;
242 for (i = 0; i < sizeof(Elf64_Rela) / sizeof(uint64_t); i++) {
249 /* Get size of potential trampolines required. */
250 static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
251 const Elf64_Shdr *sechdrs)
253 /* One extra reloc so it's always 0-funcaddr terminated */
254 unsigned long relocs = 1;
257 /* Every relocated section... */
258 for (i = 1; i < hdr->e_shnum; i++) {
259 if (sechdrs[i].sh_type == SHT_RELA) {
260 pr_debug("Found relocations in section %u\n", i);
261 pr_debug("Ptr: %p. Number: %Lu\n",
262 (void *)sechdrs[i].sh_addr,
263 sechdrs[i].sh_size / sizeof(Elf64_Rela));
265 /* Sort the relocation information based on a symbol and
266 * addend key. This is a stable O(n*log n) complexity
267 * alogrithm but it will reduce the complexity of
268 * count_relocs() to linear complexity O(n)
270 sort((void *)sechdrs[i].sh_addr,
271 sechdrs[i].sh_size / sizeof(Elf64_Rela),
272 sizeof(Elf64_Rela), relacmp, relaswap);
274 relocs += count_relocs((void *)sechdrs[i].sh_addr,
276 / sizeof(Elf64_Rela));
280 #ifdef CONFIG_DYNAMIC_FTRACE
281 /* make the trampoline to the ftrace_caller */
283 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
284 /* an additional one for ftrace_regs_caller */
289 pr_debug("Looks like a total of %lu stubs, max\n", relocs);
290 return relocs * sizeof(struct ppc64_stub_entry);
293 /* Still needed for ELFv2, for .TOC. */
294 static void dedotify_versions(struct modversion_info *vers,
297 struct modversion_info *end;
299 for (end = (void *)vers + size; vers < end; vers++)
300 if (vers->name[0] == '.') {
301 memmove(vers->name, vers->name+1, strlen(vers->name));
306 * Undefined symbols which refer to .funcname, hack to funcname. Make .TOC.
307 * seem to be defined (value set later).
309 static void dedotify(Elf64_Sym *syms, unsigned int numsyms, char *strtab)
313 for (i = 1; i < numsyms; i++) {
314 if (syms[i].st_shndx == SHN_UNDEF) {
315 char *name = strtab + syms[i].st_name;
316 if (name[0] == '.') {
317 if (strcmp(name+1, "TOC.") == 0)
318 syms[i].st_shndx = SHN_ABS;
325 static Elf64_Sym *find_dot_toc(Elf64_Shdr *sechdrs,
327 unsigned int symindex)
329 unsigned int i, numsyms;
332 syms = (Elf64_Sym *)sechdrs[symindex].sh_addr;
333 numsyms = sechdrs[symindex].sh_size / sizeof(Elf64_Sym);
335 for (i = 1; i < numsyms; i++) {
336 if (syms[i].st_shndx == SHN_ABS
337 && strcmp(strtab + syms[i].st_name, "TOC.") == 0)
343 int module_frob_arch_sections(Elf64_Ehdr *hdr,
350 /* Find .toc and .stubs sections, symtab and strtab */
351 for (i = 1; i < hdr->e_shnum; i++) {
353 if (strcmp(secstrings + sechdrs[i].sh_name, ".stubs") == 0)
354 me->arch.stubs_section = i;
355 else if (strcmp(secstrings + sechdrs[i].sh_name, ".toc") == 0) {
356 me->arch.toc_section = i;
357 if (sechdrs[i].sh_addralign < 8)
358 sechdrs[i].sh_addralign = 8;
360 else if (strcmp(secstrings+sechdrs[i].sh_name,"__versions")==0)
361 dedotify_versions((void *)hdr + sechdrs[i].sh_offset,
363 else if (!strcmp(secstrings + sechdrs[i].sh_name, ".opd")) {
364 me->arch.start_opd = sechdrs[i].sh_addr;
365 me->arch.end_opd = sechdrs[i].sh_addr +
369 /* We don't handle .init for the moment: rename to _init */
370 while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init")))
373 if (sechdrs[i].sh_type == SHT_SYMTAB)
374 dedotify((void *)hdr + sechdrs[i].sh_offset,
375 sechdrs[i].sh_size / sizeof(Elf64_Sym),
377 + sechdrs[sechdrs[i].sh_link].sh_offset);
380 if (!me->arch.stubs_section) {
381 pr_err("%s: doesn't contain .stubs.\n", me->name);
385 /* If we don't have a .toc, just use .stubs. We need to set r2
386 to some reasonable value in case the module calls out to
387 other functions via a stub, or if a function pointer escapes
388 the module by some means. */
389 if (!me->arch.toc_section)
390 me->arch.toc_section = me->arch.stubs_section;
392 /* Override the stubs size */
393 sechdrs[me->arch.stubs_section].sh_size = get_stubs_size(hdr, sechdrs);
398 * r2 is the TOC pointer: it actually points 0x8000 into the TOC (this gives the
399 * value maximum span in an instruction which uses a signed offset). Round down
400 * to a 256 byte boundary for the odd case where we are setting up r2 without a
403 static inline unsigned long my_r2(const Elf64_Shdr *sechdrs, struct module *me)
405 return (sechdrs[me->arch.toc_section].sh_addr & ~0xfful) + 0x8000;
408 /* Both low and high 16 bits are added as SIGNED additions, so if low
409 16 bits has high bit set, high 16 bits must be adjusted. These
410 macros do that (stolen from binutils). */
411 #define PPC_LO(v) ((v) & 0xffff)
412 #define PPC_HI(v) (((v) >> 16) & 0xffff)
413 #define PPC_HA(v) PPC_HI ((v) + 0x8000)
415 /* Patch stub to reference function and correct r2 value. */
416 static inline int create_stub(const Elf64_Shdr *sechdrs,
417 struct ppc64_stub_entry *entry,
423 memcpy(entry->jump, ppc64_stub_insns, sizeof(ppc64_stub_insns));
425 /* Stub uses address relative to r2. */
426 reladdr = (unsigned long)entry - my_r2(sechdrs, me);
427 if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) {
428 pr_err("%s: Address %p of stub out of range of %p.\n",
429 me->name, (void *)reladdr, (void *)my_r2);
432 pr_debug("Stub %p get data from reladdr %li\n", entry, reladdr);
434 entry->jump[0] |= PPC_HA(reladdr);
435 entry->jump[1] |= PPC_LO(reladdr);
436 entry->funcdata = func_desc(addr);
437 entry->magic = STUB_MAGIC;
442 /* Create stub to jump to function described in this OPD/ptr: we need the
443 stub to set up the TOC ptr (r2) for the function. */
444 static unsigned long stub_for_addr(const Elf64_Shdr *sechdrs,
448 struct ppc64_stub_entry *stubs;
449 unsigned int i, num_stubs;
451 num_stubs = sechdrs[me->arch.stubs_section].sh_size / sizeof(*stubs);
453 /* Find this stub, or if that fails, the next avail. entry */
454 stubs = (void *)sechdrs[me->arch.stubs_section].sh_addr;
455 for (i = 0; stub_func_addr(stubs[i].funcdata); i++) {
456 if (WARN_ON(i >= num_stubs))
459 if (stub_func_addr(stubs[i].funcdata) == func_addr(addr))
460 return (unsigned long)&stubs[i];
463 if (!create_stub(sechdrs, &stubs[i], addr, me))
466 return (unsigned long)&stubs[i];
469 #ifdef CC_USING_MPROFILE_KERNEL
470 static bool is_mprofile_mcount_callsite(const char *name, u32 *instruction)
472 if (strcmp("_mcount", name))
476 * Check if this is one of the -mprofile-kernel sequences.
478 if (instruction[-1] == PPC_INST_STD_LR &&
479 instruction[-2] == PPC_INST_MFLR)
482 if (instruction[-1] == PPC_INST_MFLR)
489 * In case of _mcount calls, do not save the current callee's TOC (in r2) into
490 * the original caller's stack frame. If we did we would clobber the saved TOC
491 * value of the original caller.
493 static void squash_toc_save_inst(const char *name, unsigned long addr)
495 struct ppc64_stub_entry *stub = (struct ppc64_stub_entry *)addr;
497 /* Only for calls to _mcount */
498 if (strcmp("_mcount", name) != 0)
501 stub->jump[2] = PPC_INST_NOP;
504 static void squash_toc_save_inst(const char *name, unsigned long addr) { }
506 static bool is_mprofile_mcount_callsite(const char *name, u32 *instruction)
512 /* We expect a noop next: if it is, replace it with instruction to
514 static int restore_r2(const char *name, u32 *instruction, struct module *me)
516 u32 *prev_insn = instruction - 1;
518 if (is_mprofile_mcount_callsite(name, prev_insn))
522 * Make sure the branch isn't a sibling call. Sibling calls aren't
523 * "link" branches and they don't return, so they don't need the r2
524 * restore afterwards.
526 if (!instr_is_relative_link_branch(*prev_insn))
529 if (*instruction != PPC_INST_NOP) {
530 pr_err("%s: Expected nop after call, got %08x at %pS\n",
531 me->name, *instruction, instruction);
534 /* ld r2,R2_STACK_OFFSET(r1) */
535 *instruction = PPC_INST_LD_TOC;
539 int apply_relocate_add(Elf64_Shdr *sechdrs,
541 unsigned int symindex,
546 Elf64_Rela *rela = (void *)sechdrs[relsec].sh_addr;
548 unsigned long *location;
551 pr_debug("Applying ADD relocate section %u to %u\n", relsec,
552 sechdrs[relsec].sh_info);
554 /* First time we're called, we can fix up .TOC. */
555 if (!me->arch.toc_fixed) {
556 sym = find_dot_toc(sechdrs, strtab, symindex);
557 /* It's theoretically possible that a module doesn't want a
558 * .TOC. so don't fail it just for that. */
560 sym->st_value = my_r2(sechdrs, me);
561 me->arch.toc_fixed = true;
564 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
565 /* This is where to make the change */
566 location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
568 /* This is the symbol it is referring to */
569 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
570 + ELF64_R_SYM(rela[i].r_info);
572 pr_debug("RELOC at %p: %li-type as %s (0x%lx) + %li\n",
573 location, (long)ELF64_R_TYPE(rela[i].r_info),
574 strtab + sym->st_name, (unsigned long)sym->st_value,
575 (long)rela[i].r_addend);
577 /* `Everything is relative'. */
578 value = sym->st_value + rela[i].r_addend;
580 switch (ELF64_R_TYPE(rela[i].r_info)) {
583 *(u32 *)location = value;
588 *(unsigned long *)location = value;
592 *(unsigned long *)location = my_r2(sechdrs, me);
596 /* Subtract TOC pointer */
597 value -= my_r2(sechdrs, me);
598 if (value + 0x8000 > 0xffff) {
599 pr_err("%s: bad TOC16 relocation (0x%lx)\n",
603 *((uint16_t *) location)
604 = (*((uint16_t *) location) & ~0xffff)
608 case R_PPC64_TOC16_LO:
609 /* Subtract TOC pointer */
610 value -= my_r2(sechdrs, me);
611 *((uint16_t *) location)
612 = (*((uint16_t *) location) & ~0xffff)
616 case R_PPC64_TOC16_DS:
617 /* Subtract TOC pointer */
618 value -= my_r2(sechdrs, me);
619 if ((value & 3) != 0 || value + 0x8000 > 0xffff) {
620 pr_err("%s: bad TOC16_DS relocation (0x%lx)\n",
624 *((uint16_t *) location)
625 = (*((uint16_t *) location) & ~0xfffc)
629 case R_PPC64_TOC16_LO_DS:
630 /* Subtract TOC pointer */
631 value -= my_r2(sechdrs, me);
632 if ((value & 3) != 0) {
633 pr_err("%s: bad TOC16_LO_DS relocation (0x%lx)\n",
637 *((uint16_t *) location)
638 = (*((uint16_t *) location) & ~0xfffc)
642 case R_PPC64_TOC16_HA:
643 /* Subtract TOC pointer */
644 value -= my_r2(sechdrs, me);
645 value = ((value + 0x8000) >> 16);
646 *((uint16_t *) location)
647 = (*((uint16_t *) location) & ~0xffff)
652 /* FIXME: Handle weak symbols here --RR */
653 if (sym->st_shndx == SHN_UNDEF ||
654 sym->st_shndx == SHN_LIVEPATCH) {
655 /* External: go via stub */
656 value = stub_for_addr(sechdrs, value, me);
659 if (!restore_r2(strtab + sym->st_name,
660 (u32 *)location + 1, me))
663 squash_toc_save_inst(strtab + sym->st_name, value);
665 value += local_entry_offset(sym);
667 /* Convert value to relative */
668 value -= (unsigned long)location;
669 if (value + 0x2000000 > 0x3ffffff || (value & 3) != 0){
670 pr_err("%s: REL24 %li out of range!\n",
671 me->name, (long int)value);
675 /* Only replace bits 2 through 26 */
676 *(uint32_t *)location
677 = (*(uint32_t *)location & ~0x03fffffc)
678 | (value & 0x03fffffc);
682 /* 64 bits relative (used by features fixups) */
683 *location = value - (unsigned long)location;
687 /* 32 bits relative (used by relative exception tables) */
688 *(u32 *)location = value - (unsigned long)location;
691 case R_PPC64_TOCSAVE:
693 * Marker reloc indicates we don't have to save r2.
694 * That would only save us one instruction, so ignore
701 * Optimize ELFv2 large code model entry point if
702 * the TOC is within 2GB range of current location.
704 value = my_r2(sechdrs, me) - (unsigned long)location;
705 if (value + 0x80008000 > 0xffffffff)
708 * Check for the large code model prolog sequence:
712 if ((((uint32_t *)location)[0] & ~0xfffc)
715 if (((uint32_t *)location)[1] != 0x7c426214)
718 * If found, replace it with:
719 * addis r2, r12, (.TOC.-func)@ha
720 * addi r2, r12, (.TOC.-func)@l
722 ((uint32_t *)location)[0] = 0x3c4c0000 + PPC_HA(value);
723 ((uint32_t *)location)[1] = 0x38420000 + PPC_LO(value);
726 case R_PPC64_REL16_HA:
727 /* Subtract location pointer */
728 value -= (unsigned long)location;
729 value = ((value + 0x8000) >> 16);
730 *((uint16_t *) location)
731 = (*((uint16_t *) location) & ~0xffff)
735 case R_PPC64_REL16_LO:
736 /* Subtract location pointer */
737 value -= (unsigned long)location;
738 *((uint16_t *) location)
739 = (*((uint16_t *) location) & ~0xffff)
744 pr_err("%s: Unknown ADD relocation: %lu\n",
746 (unsigned long)ELF64_R_TYPE(rela[i].r_info));
754 #ifdef CONFIG_DYNAMIC_FTRACE
756 #ifdef CC_USING_MPROFILE_KERNEL
758 #define PACATOC offsetof(struct paca_struct, kernel_toc)
761 * For mprofile-kernel we use a special stub for ftrace_caller() because we
762 * can't rely on r2 containing this module's TOC when we enter the stub.
764 * That can happen if the function calling us didn't need to use the toc. In
765 * that case it won't have setup r2, and the r2 value will be either the
766 * kernel's toc, or possibly another modules toc.
768 * To deal with that this stub uses the kernel toc, which is always accessible
769 * via the paca (in r13). The target (ftrace_caller()) is responsible for
770 * saving and restoring the toc before returning.
772 static unsigned long create_ftrace_stub(const Elf64_Shdr *sechdrs,
773 struct module *me, unsigned long addr)
775 struct ppc64_stub_entry *entry;
776 unsigned int i, num_stubs;
777 static u32 stub_insns[] = {
778 0xe98d0000 | PACATOC, /* ld r12,PACATOC(r13) */
779 0x3d8c0000, /* addis r12,r12,<high> */
780 0x398c0000, /* addi r12,r12,<low> */
781 0x7d8903a6, /* mtctr r12 */
782 0x4e800420, /* bctr */
786 num_stubs = sechdrs[me->arch.stubs_section].sh_size / sizeof(*entry);
788 /* Find the next available stub entry */
789 entry = (void *)sechdrs[me->arch.stubs_section].sh_addr;
790 for (i = 0; i < num_stubs && stub_func_addr(entry->funcdata); i++, entry++);
792 if (i >= num_stubs) {
793 pr_err("%s: Unable to find a free slot for ftrace stub.\n", me->name);
797 memcpy(entry->jump, stub_insns, sizeof(stub_insns));
799 /* Stub uses address relative to kernel toc (from the paca) */
800 reladdr = addr - kernel_toc_addr();
801 if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) {
802 pr_err("%s: Address of %ps out of range of kernel_toc.\n",
803 me->name, (void *)addr);
807 entry->jump[1] |= PPC_HA(reladdr);
808 entry->jump[2] |= PPC_LO(reladdr);
810 /* Eventhough we don't use funcdata in the stub, it's needed elsewhere. */
811 entry->funcdata = func_desc(addr);
812 entry->magic = STUB_MAGIC;
814 return (unsigned long)entry;
817 static unsigned long create_ftrace_stub(const Elf64_Shdr *sechdrs,
818 struct module *me, unsigned long addr)
820 return stub_for_addr(sechdrs, addr, me);
824 int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
826 mod->arch.tramp = create_ftrace_stub(sechdrs, mod,
827 (unsigned long)ftrace_caller);
828 #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS
829 mod->arch.tramp_regs = create_ftrace_stub(sechdrs, mod,
830 (unsigned long)ftrace_regs_caller);
831 if (!mod->arch.tramp_regs)
835 if (!mod->arch.tramp)