1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Kernel dynamically loadable module help for PARISC.
4 * The best reference for this stuff is probably the Processor-
5 * Specific ELF Supplement for PA-RISC:
6 * http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
8 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
9 * Copyright (C) 2003 Randolph Chung <tausq at debian . org>
10 * Copyright (C) 2008 Helge Deller <deller@gmx.de>
14 * On 32bit (and sometimes 64bit) and with big kernel modules like xfs or
15 * ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may
16 * fail to reach their PLT stub if we only create one big stub array for
17 * all sections at the beginning of the core or init section.
18 * Instead we now insert individual PLT stub entries directly in front of
19 * of the code sections where the stubs are actually called.
20 * This reduces the distance between the PCREL location and the stub entry
21 * so that the relocations can be fulfilled.
22 * While calculating the final layout of the kernel module in memory, the
23 * kernel module loader calls arch_mod_section_prepend() to request the
24 * to be reserved amount of memory in front of each individual section.
27 * We are not doing SEGREL32 handling correctly. According to the ABI, we
28 * should do a value offset, like this:
29 * if (in_init(me, (void *)val))
30 * val -= (uint32_t)me->init_layout.base;
32 * val -= (uint32_t)me->core_layout.base;
33 * However, SEGREL32 is used only for PARISC unwind entries, and we want
34 * those entries to have an absolute address, and not just an offset.
36 * The unwind table mechanism has the ability to specify an offset for
37 * the unwind table; however, because we split off the init functions into
38 * a different piece of memory, it is not possible to do this using a
39 * single offset. Instead, we use the above hack for now.
42 #include <linux/moduleloader.h>
43 #include <linux/elf.h>
44 #include <linux/vmalloc.h>
46 #include <linux/string.h>
47 #include <linux/kernel.h>
48 #include <linux/bug.h>
50 #include <linux/slab.h>
52 #include <asm/pgtable.h>
53 #include <asm/unwind.h>
54 #include <asm/sections.h>
59 #define DEBUGP(fmt...)
62 #define RELOC_REACHABLE(val, bits) \
63 (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \
64 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
67 #define CHECK_RELOC(val, bits) \
68 if (!RELOC_REACHABLE(val, bits)) { \
69 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
70 me->name, strtab + sym->st_name, (unsigned long)val, bits); \
74 /* Maximum number of GOT entries. We use a long displacement ldd from
75 * the bottom of the table, which has a maximum signed displacement of
76 * 0x3fff; however, since we're only going forward, this becomes
77 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
78 * at most 1023 entries.
79 * To overcome this 14bit displacement with some kernel modules, we'll
80 * use instead the unusal 16bit displacement method (see reassemble_16a)
81 * which gives us a maximum positive displacement of 0x7fff, and as such
82 * allows us to allocate up to 4095 GOT entries. */
85 /* three functions to determine where in the module core
86 * or init pieces the location is */
87 static inline int in_init(struct module *me, void *loc)
89 return (loc >= me->init_layout.base &&
90 loc <= (me->init_layout.base + me->init_layout.size));
93 static inline int in_core(struct module *me, void *loc)
95 return (loc >= me->core_layout.base &&
96 loc <= (me->core_layout.base + me->core_layout.size));
99 static inline int in_local(struct module *me, void *loc)
101 return in_init(me, loc) || in_core(me, loc);
110 Elf32_Word insns[2]; /* each stub entry has two insns */
118 Elf64_Word insns[4]; /* each stub entry has four insns */
122 /* Field selection types defined by hppa */
123 #define rnd(x) (((x)+0x1000)&~0x1fff)
124 /* fsel: full 32 bits */
125 #define fsel(v,a) ((v)+(a))
126 /* lsel: select left 21 bits */
127 #define lsel(v,a) (((v)+(a))>>11)
128 /* rsel: select right 11 bits */
129 #define rsel(v,a) (((v)+(a))&0x7ff)
130 /* lrsel with rounding of addend to nearest 8k */
131 #define lrsel(v,a) (((v)+rnd(a))>>11)
132 /* rrsel with rounding of addend to nearest 8k */
133 #define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
135 #define mask(x,sz) ((x) & ~((1<<(sz))-1))
138 /* The reassemble_* functions prepare an immediate value for
139 insertion into an opcode. pa-risc uses all sorts of weird bitfields
140 in the instruction to hold the value. */
141 static inline int sign_unext(int x, int len)
145 len_ones = (1 << len) - 1;
149 static inline int low_sign_unext(int x, int len)
153 sign = (x >> (len-1)) & 1;
154 temp = sign_unext(x, len-1);
155 return (temp << 1) | sign;
158 static inline int reassemble_14(int as14)
160 return (((as14 & 0x1fff) << 1) |
161 ((as14 & 0x2000) >> 13));
164 static inline int reassemble_16a(int as16)
168 /* Unusual 16-bit encoding, for wide mode only. */
169 t = (as16 << 1) & 0xffff;
171 return (t ^ s ^ (s >> 1)) | (s >> 15);
175 static inline int reassemble_17(int as17)
177 return (((as17 & 0x10000) >> 16) |
178 ((as17 & 0x0f800) << 5) |
179 ((as17 & 0x00400) >> 8) |
180 ((as17 & 0x003ff) << 3));
183 static inline int reassemble_21(int as21)
185 return (((as21 & 0x100000) >> 20) |
186 ((as21 & 0x0ffe00) >> 8) |
187 ((as21 & 0x000180) << 7) |
188 ((as21 & 0x00007c) << 14) |
189 ((as21 & 0x000003) << 12));
192 static inline int reassemble_22(int as22)
194 return (((as22 & 0x200000) >> 21) |
195 ((as22 & 0x1f0000) << 5) |
196 ((as22 & 0x00f800) << 5) |
197 ((as22 & 0x000400) >> 8) |
198 ((as22 & 0x0003ff) << 3));
201 void *module_alloc(unsigned long size)
203 /* using RWX means less protection for modules, but it's
204 * easier than trying to map the text, data, init_text and
205 * init_data correctly */
206 return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
208 PAGE_KERNEL_RWX, 0, NUMA_NO_NODE,
209 __builtin_return_address(0));
213 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
218 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
223 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
225 unsigned long cnt = 0;
227 for (; n > 0; n--, rela++)
229 switch (ELF32_R_TYPE(rela->r_info)) {
230 case R_PARISC_PCREL17F:
231 case R_PARISC_PCREL22F:
239 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
241 unsigned long cnt = 0;
243 for (; n > 0; n--, rela++)
245 switch (ELF64_R_TYPE(rela->r_info)) {
246 case R_PARISC_LTOFF21L:
247 case R_PARISC_LTOFF14R:
248 case R_PARISC_PCREL22F:
256 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
258 unsigned long cnt = 0;
260 for (; n > 0; n--, rela++)
262 switch (ELF64_R_TYPE(rela->r_info)) {
263 case R_PARISC_FPTR64:
271 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
273 unsigned long cnt = 0;
275 for (; n > 0; n--, rela++)
277 switch (ELF64_R_TYPE(rela->r_info)) {
278 case R_PARISC_PCREL22F:
287 void module_arch_freeing_init(struct module *mod)
289 kfree(mod->arch.section);
290 mod->arch.section = NULL;
293 /* Additional bytes needed in front of individual sections */
294 unsigned int arch_mod_section_prepend(struct module *mod,
295 unsigned int section)
297 /* size needed for all stubs of this section (including
298 * one additional for correct alignment of the stubs) */
299 return (mod->arch.section[section].stub_entries + 1)
300 * sizeof(struct stub_entry);
304 int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
305 CONST Elf_Shdr *sechdrs,
306 CONST char *secstrings,
309 unsigned long gots = 0, fdescs = 0, len;
312 len = hdr->e_shnum * sizeof(me->arch.section[0]);
313 me->arch.section = kzalloc(len, GFP_KERNEL);
314 if (!me->arch.section)
317 for (i = 1; i < hdr->e_shnum; i++) {
318 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
319 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
320 unsigned int count, s;
322 if (strncmp(secstrings + sechdrs[i].sh_name,
323 ".PARISC.unwind", 14) == 0)
324 me->arch.unwind_section = i;
326 if (sechdrs[i].sh_type != SHT_RELA)
329 /* some of these are not relevant for 32-bit/64-bit
330 * we leave them here to make the code common. the
331 * compiler will do its thing and optimize out the
332 * stuff we don't need
334 gots += count_gots(rels, nrels);
335 fdescs += count_fdescs(rels, nrels);
337 /* XXX: By sorting the relocs and finding duplicate entries
338 * we could reduce the number of necessary stubs and save
340 count = count_stubs(rels, nrels);
344 /* so we need relocation stubs. reserve necessary memory. */
345 /* sh_info gives the section for which we need to add stubs. */
346 s = sechdrs[i].sh_info;
348 /* each code section should only have one relocation section */
349 WARN_ON(me->arch.section[s].stub_entries);
351 /* store number of stubs we need for this section */
352 me->arch.section[s].stub_entries += count;
355 /* align things a bit */
356 me->core_layout.size = ALIGN(me->core_layout.size, 16);
357 me->arch.got_offset = me->core_layout.size;
358 me->core_layout.size += gots * sizeof(struct got_entry);
360 me->core_layout.size = ALIGN(me->core_layout.size, 16);
361 me->arch.fdesc_offset = me->core_layout.size;
362 me->core_layout.size += fdescs * sizeof(Elf_Fdesc);
364 me->arch.got_max = gots;
365 me->arch.fdesc_max = fdescs;
371 static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
374 struct got_entry *got;
380 got = me->core_layout.base + me->arch.got_offset;
381 for (i = 0; got[i].addr; i++)
382 if (got[i].addr == value)
385 BUG_ON(++me->arch.got_count > me->arch.got_max);
389 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
391 return i * sizeof(struct got_entry);
393 #endif /* CONFIG_64BIT */
396 static Elf_Addr get_fdesc(struct module *me, unsigned long value)
398 Elf_Fdesc *fdesc = me->core_layout.base + me->arch.fdesc_offset;
401 printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
405 /* Look for existing fdesc entry. */
406 while (fdesc->addr) {
407 if (fdesc->addr == value)
408 return (Elf_Addr)fdesc;
412 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
416 fdesc->gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset;
417 return (Elf_Addr)fdesc;
419 #endif /* CONFIG_64BIT */
427 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
428 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
430 struct stub_entry *stub;
431 int __maybe_unused d;
433 /* initialize stub_offset to point in front of the section */
434 if (!me->arch.section[targetsec].stub_offset) {
435 loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
436 sizeof(struct stub_entry);
437 /* get correct alignment for the stubs */
438 loc0 = ALIGN(loc0, sizeof(struct stub_entry));
439 me->arch.section[targetsec].stub_offset = loc0;
442 /* get address of stub entry */
443 stub = (void *) me->arch.section[targetsec].stub_offset;
444 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
446 /* do not write outside available stub area */
447 BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
451 /* for 32-bit the stub looks like this:
453 * be,n R'XXX(%sr4,%r1)
455 //value = *(unsigned long *)((value + addend) & ~3); /* why? */
457 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */
458 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */
460 stub->insns[0] |= reassemble_21(lrsel(value, addend));
461 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
464 /* for 64-bit we have three kinds of stubs:
465 * for normal function calls:
477 * for direct branches (jumps between different section of the
485 d = get_got(me, value, addend);
488 stub->insns[0] = 0x0f6010db; /* ldd 0(%dp),%dp */
489 stub->insns[0] |= low_sign_unext(d, 5) << 16;
492 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */
493 stub->insns[0] |= reassemble_16a(d);
495 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */
496 stub->insns[2] = 0xe820d000; /* bve (%r1) */
497 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */
500 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
501 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
502 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */
503 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */
505 stub->insns[0] |= reassemble_21(lrsel(value, addend));
506 stub->insns[1] |= reassemble_14(rrsel(value, addend));
508 case ELF_STUB_DIRECT:
509 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
510 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
511 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */
513 stub->insns[0] |= reassemble_21(lrsel(value, addend));
514 stub->insns[1] |= reassemble_14(rrsel(value, addend));
520 return (Elf_Addr)stub;
524 int apply_relocate_add(Elf_Shdr *sechdrs,
526 unsigned int symindex,
531 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
538 unsigned int targetsec = sechdrs[relsec].sh_info;
539 //unsigned long dp = (unsigned long)$global$;
540 register unsigned long dp asm ("r27");
542 DEBUGP("Applying relocate section %u to %u\n", relsec,
544 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
545 /* This is where to make the change */
546 loc = (void *)sechdrs[targetsec].sh_addr
548 /* This is the start of the target section */
549 loc0 = sechdrs[targetsec].sh_addr;
550 /* This is the symbol it is referring to */
551 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
552 + ELF32_R_SYM(rel[i].r_info);
553 if (!sym->st_value) {
554 printk(KERN_WARNING "%s: Unknown symbol %s\n",
555 me->name, strtab + sym->st_name);
558 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
559 dot = (Elf32_Addr)loc & ~0x03;
562 addend = rel[i].r_addend;
565 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
566 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
567 strtab + sym->st_name,
568 (uint32_t)loc, val, addend,
582 switch (ELF32_R_TYPE(rel[i].r_info)) {
583 case R_PARISC_PLABEL32:
584 /* 32-bit function address */
585 /* no function descriptors... */
586 *loc = fsel(val, addend);
589 /* direct 32-bit ref */
590 *loc = fsel(val, addend);
592 case R_PARISC_DIR21L:
593 /* left 21 bits of effective address */
594 val = lrsel(val, addend);
595 *loc = mask(*loc, 21) | reassemble_21(val);
597 case R_PARISC_DIR14R:
598 /* right 14 bits of effective address */
599 val = rrsel(val, addend);
600 *loc = mask(*loc, 14) | reassemble_14(val);
602 case R_PARISC_SEGREL32:
603 /* 32-bit segment relative address */
604 /* See note about special handling of SEGREL32 at
605 * the beginning of this file.
607 *loc = fsel(val, addend);
609 case R_PARISC_SECREL32:
610 /* 32-bit section relative address. */
611 *loc = fsel(val, addend);
613 case R_PARISC_DPREL21L:
614 /* left 21 bit of relative address */
615 val = lrsel(val - dp, addend);
616 *loc = mask(*loc, 21) | reassemble_21(val);
618 case R_PARISC_DPREL14R:
619 /* right 14 bit of relative address */
620 val = rrsel(val - dp, addend);
621 *loc = mask(*loc, 14) | reassemble_14(val);
623 case R_PARISC_PCREL17F:
624 /* 17-bit PC relative address */
625 /* calculate direct call offset */
627 val = (val - dot - 8)/4;
628 if (!RELOC_REACHABLE(val, 17)) {
629 /* direct distance too far, create
630 * stub entry instead */
631 val = get_stub(me, sym->st_value, addend,
632 ELF_STUB_DIRECT, loc0, targetsec);
633 val = (val - dot - 8)/4;
634 CHECK_RELOC(val, 17);
636 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
638 case R_PARISC_PCREL22F:
639 /* 22-bit PC relative address; only defined for pa20 */
640 /* calculate direct call offset */
642 val = (val - dot - 8)/4;
643 if (!RELOC_REACHABLE(val, 22)) {
644 /* direct distance too far, create
645 * stub entry instead */
646 val = get_stub(me, sym->st_value, addend,
647 ELF_STUB_DIRECT, loc0, targetsec);
648 val = (val - dot - 8)/4;
649 CHECK_RELOC(val, 22);
651 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
653 case R_PARISC_PCREL32:
654 /* 32-bit PC relative address */
655 *loc = val - dot - 8 + addend;
659 printk(KERN_ERR "module %s: Unknown relocation: %u\n",
660 me->name, ELF32_R_TYPE(rel[i].r_info));
669 int apply_relocate_add(Elf_Shdr *sechdrs,
671 unsigned int symindex,
676 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
684 unsigned int targetsec = sechdrs[relsec].sh_info;
686 DEBUGP("Applying relocate section %u to %u\n", relsec,
688 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
689 /* This is where to make the change */
690 loc = (void *)sechdrs[targetsec].sh_addr
692 /* This is the start of the target section */
693 loc0 = sechdrs[targetsec].sh_addr;
694 /* This is the symbol it is referring to */
695 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
696 + ELF64_R_SYM(rel[i].r_info);
697 if (!sym->st_value) {
698 printk(KERN_WARNING "%s: Unknown symbol %s\n",
699 me->name, strtab + sym->st_name);
702 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
703 dot = (Elf64_Addr)loc & ~0x03;
704 loc64 = (Elf64_Xword *)loc;
707 addend = rel[i].r_addend;
710 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
711 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
712 strtab + sym->st_name,
724 switch (ELF64_R_TYPE(rel[i].r_info)) {
725 case R_PARISC_LTOFF21L:
726 /* LT-relative; left 21 bits */
727 val = get_got(me, val, addend);
728 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
729 strtab + sym->st_name,
732 *loc = mask(*loc, 21) | reassemble_21(val);
734 case R_PARISC_LTOFF14R:
735 /* L(ltoff(val+addend)) */
736 /* LT-relative; right 14 bits */
737 val = get_got(me, val, addend);
739 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
740 strtab + sym->st_name,
742 *loc = mask(*loc, 14) | reassemble_14(val);
744 case R_PARISC_PCREL22F:
745 /* PC-relative; 22 bits */
746 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
747 strtab + sym->st_name,
750 /* can we reach it locally? */
751 if (in_local(me, (void *)val)) {
752 /* this is the case where the symbol is local
753 * to the module, but in a different section,
754 * so stub the jump in case it's more than 22
756 val = (val - dot - 8)/4;
757 if (!RELOC_REACHABLE(val, 22)) {
758 /* direct distance too far, create
759 * stub entry instead */
760 val = get_stub(me, sym->st_value,
761 addend, ELF_STUB_DIRECT,
764 /* Ok, we can reach it directly. */
770 if (strncmp(strtab + sym->st_name, "$$", 2)
772 val = get_stub(me, val, addend, ELF_STUB_MILLI,
775 val = get_stub(me, val, addend, ELF_STUB_GOT,
778 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
779 strtab + sym->st_name, loc, sym->st_value,
781 val = (val - dot - 8)/4;
782 CHECK_RELOC(val, 22);
783 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
785 case R_PARISC_PCREL32:
786 /* 32-bit PC relative address */
787 *loc = val - dot - 8 + addend;
789 case R_PARISC_PCREL64:
790 /* 64-bit PC relative address */
791 *loc64 = val - dot - 8 + addend;
794 /* 64-bit effective address */
795 *loc64 = val + addend;
797 case R_PARISC_SEGREL32:
798 /* 32-bit segment relative address */
799 /* See note about special handling of SEGREL32 at
800 * the beginning of this file.
802 *loc = fsel(val, addend);
804 case R_PARISC_SECREL32:
805 /* 32-bit section relative address. */
806 *loc = fsel(val, addend);
808 case R_PARISC_FPTR64:
809 /* 64-bit function address */
810 if(in_local(me, (void *)(val + addend))) {
811 *loc64 = get_fdesc(me, val+addend);
812 DEBUGP("FDESC for %s at %p points to %lx\n",
813 strtab + sym->st_name, *loc64,
814 ((Elf_Fdesc *)*loc64)->addr);
816 /* if the symbol is not local to this
817 * module then val+addend is a pointer
818 * to the function descriptor */
819 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
820 strtab + sym->st_name,
822 *loc64 = val + addend;
827 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
828 me->name, ELF64_R_TYPE(rel[i].r_info));
837 register_unwind_table(struct module *me,
838 const Elf_Shdr *sechdrs)
840 unsigned char *table, *end;
843 if (!me->arch.unwind_section)
846 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
847 end = table + sechdrs[me->arch.unwind_section].sh_size;
848 gp = (Elf_Addr)me->core_layout.base + me->arch.got_offset;
850 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
851 me->arch.unwind_section, table, end, gp);
852 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
856 deregister_unwind_table(struct module *me)
859 unwind_table_remove(me->arch.unwind);
862 int module_finalize(const Elf_Ehdr *hdr,
863 const Elf_Shdr *sechdrs,
868 const char *strtab = NULL;
871 Elf_Sym *newptr, *oldptr;
872 Elf_Shdr *symhdr = NULL;
877 entry = (Elf_Fdesc *)me->init;
878 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
879 entry->gp, entry->addr);
880 addr = (u32 *)entry->addr;
881 printk("INSNS: %x %x %x %x\n",
882 addr[0], addr[1], addr[2], addr[3]);
883 printk("got entries used %ld, gots max %ld\n"
884 "fdescs used %ld, fdescs max %ld\n",
885 me->arch.got_count, me->arch.got_max,
886 me->arch.fdesc_count, me->arch.fdesc_max);
889 register_unwind_table(me, sechdrs);
891 /* haven't filled in me->symtab yet, so have to find it
893 for (i = 1; i < hdr->e_shnum; i++) {
894 if(sechdrs[i].sh_type == SHT_SYMTAB
895 && (sechdrs[i].sh_flags & SHF_ALLOC)) {
896 int strindex = sechdrs[i].sh_link;
898 * The cast is to drop the const from
899 * the sechdrs pointer */
900 symhdr = (Elf_Shdr *)&sechdrs[i];
901 strtab = (char *)sechdrs[strindex].sh_addr;
906 DEBUGP("module %s: strtab %p, symhdr %p\n",
907 me->name, strtab, symhdr);
909 if(me->arch.got_count > MAX_GOTS) {
910 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
911 me->name, me->arch.got_count, MAX_GOTS);
915 kfree(me->arch.section);
916 me->arch.section = NULL;
918 /* no symbol table */
922 oldptr = (void *)symhdr->sh_addr;
923 newptr = oldptr + 1; /* we start counting at 1 */
924 nsyms = symhdr->sh_size / sizeof(Elf_Sym);
925 DEBUGP("OLD num_symtab %lu\n", nsyms);
927 for (i = 1; i < nsyms; i++) {
928 oldptr++; /* note, count starts at 1 so preincrement */
929 if(strncmp(strtab + oldptr->st_name,
939 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
940 DEBUGP("NEW num_symtab %lu\n", nsyms);
941 symhdr->sh_size = nsyms * sizeof(Elf_Sym);
943 /* find .altinstructions section */
944 secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
945 for (s = sechdrs; s < sechdrs + hdr->e_shnum; s++) {
946 void *aseg = (void *) s->sh_addr;
947 char *secname = secstrings + s->sh_name;
949 if (!strcmp(".altinstructions", secname))
950 /* patch .altinstructions */
951 apply_alternatives(aseg, aseg + s->sh_size, me->name);
957 void module_arch_cleanup(struct module *mod)
959 deregister_unwind_table(mod);
963 void *dereference_module_function_descriptor(struct module *mod, void *ptr)
965 unsigned long start_opd = (Elf64_Addr)mod->core_layout.base +
966 mod->arch.fdesc_offset;
967 unsigned long end_opd = start_opd +
968 mod->arch.fdesc_count * sizeof(Elf64_Fdesc);
970 if (ptr < (void *)start_opd || ptr >= (void *)end_opd)
973 return dereference_function_descriptor(ptr);