1 /* Kernel dynamically loadable module help for PARISC.
3 * The best reference for this stuff is probably the Processor-
4 * Specific ELF Supplement for PA-RISC:
5 * http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
7 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
8 * Copyright (C) 2003 Randolph Chung <tausq at debian . org>
9 * Copyright (C) 2008 Helge Deller <deller@gmx.de>
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29 * On 32bit (and sometimes 64bit) and with big kernel modules like xfs or
30 * ipv6 the relocation types R_PARISC_PCREL17F and R_PARISC_PCREL22F may
31 * fail to reach their PLT stub if we only create one big stub array for
32 * all sections at the beginning of the core or init section.
33 * Instead we now insert individual PLT stub entries directly in front of
34 * of the code sections where the stubs are actually called.
35 * This reduces the distance between the PCREL location and the stub entry
36 * so that the relocations can be fulfilled.
37 * While calculating the final layout of the kernel module in memory, the
38 * kernel module loader calls arch_mod_section_prepend() to request the
39 * to be reserved amount of memory in front of each individual section.
42 * We are not doing SEGREL32 handling correctly. According to the ABI, we
43 * should do a value offset, like this:
44 * if (in_init(me, (void *)val))
45 * val -= (uint32_t)me->module_init;
47 * val -= (uint32_t)me->module_core;
48 * However, SEGREL32 is used only for PARISC unwind entries, and we want
49 * those entries to have an absolute address, and not just an offset.
51 * The unwind table mechanism has the ability to specify an offset for
52 * the unwind table; however, because we split off the init functions into
53 * a different piece of memory, it is not possible to do this using a
54 * single offset. Instead, we use the above hack for now.
57 #include <linux/moduleloader.h>
58 #include <linux/elf.h>
59 #include <linux/vmalloc.h>
61 #include <linux/string.h>
62 #include <linux/kernel.h>
63 #include <linux/bug.h>
64 #include <linux/uaccess.h>
66 #include <asm/sections.h>
67 #include <asm/unwind.h>
72 #define DEBUGP(fmt...)
75 #define RELOC_REACHABLE(val, bits) \
76 (( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \
77 ( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) ? \
80 #define CHECK_RELOC(val, bits) \
81 if (!RELOC_REACHABLE(val, bits)) { \
82 printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
83 me->name, strtab + sym->st_name, (unsigned long)val, bits); \
87 /* Maximum number of GOT entries. We use a long displacement ldd from
88 * the bottom of the table, which has a maximum signed displacement of
89 * 0x3fff; however, since we're only going forward, this becomes
90 * 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
91 * at most 1023 entries */
94 /* three functions to determine where in the module core
95 * or init pieces the location is */
96 static inline int in_init(struct module *me, void *loc)
98 return (loc >= me->module_init &&
99 loc <= (me->module_init + me->init_size));
102 static inline int in_core(struct module *me, void *loc)
104 return (loc >= me->module_core &&
105 loc <= (me->module_core + me->core_size));
108 static inline int in_local(struct module *me, void *loc)
110 return in_init(me, loc) || in_core(me, loc);
119 Elf32_Word insns[2]; /* each stub entry has two insns */
127 Elf64_Word insns[4]; /* each stub entry has four insns */
131 /* Field selection types defined by hppa */
132 #define rnd(x) (((x)+0x1000)&~0x1fff)
133 /* fsel: full 32 bits */
134 #define fsel(v,a) ((v)+(a))
135 /* lsel: select left 21 bits */
136 #define lsel(v,a) (((v)+(a))>>11)
137 /* rsel: select right 11 bits */
138 #define rsel(v,a) (((v)+(a))&0x7ff)
139 /* lrsel with rounding of addend to nearest 8k */
140 #define lrsel(v,a) (((v)+rnd(a))>>11)
141 /* rrsel with rounding of addend to nearest 8k */
142 #define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
144 #define mask(x,sz) ((x) & ~((1<<(sz))-1))
147 /* The reassemble_* functions prepare an immediate value for
148 insertion into an opcode. pa-risc uses all sorts of weird bitfields
149 in the instruction to hold the value. */
150 static inline int reassemble_14(int as14)
152 return (((as14 & 0x1fff) << 1) |
153 ((as14 & 0x2000) >> 13));
156 static inline int reassemble_17(int as17)
158 return (((as17 & 0x10000) >> 16) |
159 ((as17 & 0x0f800) << 5) |
160 ((as17 & 0x00400) >> 8) |
161 ((as17 & 0x003ff) << 3));
164 static inline int reassemble_21(int as21)
166 return (((as21 & 0x100000) >> 20) |
167 ((as21 & 0x0ffe00) >> 8) |
168 ((as21 & 0x000180) << 7) |
169 ((as21 & 0x00007c) << 14) |
170 ((as21 & 0x000003) << 12));
173 static inline int reassemble_22(int as22)
175 return (((as22 & 0x200000) >> 21) |
176 ((as22 & 0x1f0000) << 5) |
177 ((as22 & 0x00f800) << 5) |
178 ((as22 & 0x000400) >> 8) |
179 ((as22 & 0x0003ff) << 3));
182 void *module_alloc(unsigned long size)
186 return vmalloc(size);
190 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
195 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
200 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
202 unsigned long cnt = 0;
204 for (; n > 0; n--, rela++)
206 switch (ELF32_R_TYPE(rela->r_info)) {
207 case R_PARISC_PCREL17F:
208 case R_PARISC_PCREL22F:
216 static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
218 unsigned long cnt = 0;
220 for (; n > 0; n--, rela++)
222 switch (ELF64_R_TYPE(rela->r_info)) {
223 case R_PARISC_LTOFF21L:
224 case R_PARISC_LTOFF14R:
225 case R_PARISC_PCREL22F:
233 static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
235 unsigned long cnt = 0;
237 for (; n > 0; n--, rela++)
239 switch (ELF64_R_TYPE(rela->r_info)) {
240 case R_PARISC_FPTR64:
248 static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
250 unsigned long cnt = 0;
252 for (; n > 0; n--, rela++)
254 switch (ELF64_R_TYPE(rela->r_info)) {
255 case R_PARISC_PCREL22F:
265 /* Free memory returned from module_alloc */
266 void module_free(struct module *mod, void *module_region)
268 kfree(mod->arch.section);
269 mod->arch.section = NULL;
271 vfree(module_region);
272 /* FIXME: If module_region == mod->init_region, trim exception
276 /* Additional bytes needed in front of individual sections */
277 unsigned int arch_mod_section_prepend(struct module *mod,
278 unsigned int section)
280 /* size needed for all stubs of this section (including
281 * one additional for correct alignment of the stubs) */
282 return (mod->arch.section[section].stub_entries + 1)
283 * sizeof(struct stub_entry);
287 int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
288 CONST Elf_Shdr *sechdrs,
289 CONST char *secstrings,
292 unsigned long gots = 0, fdescs = 0, len;
295 len = hdr->e_shnum * sizeof(me->arch.section[0]);
296 me->arch.section = kzalloc(len, GFP_KERNEL);
297 if (!me->arch.section)
300 for (i = 1; i < hdr->e_shnum; i++) {
301 const Elf_Rela *rels = (void *)sechdrs[i].sh_addr;
302 unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
303 unsigned int count, s;
305 if (strncmp(secstrings + sechdrs[i].sh_name,
306 ".PARISC.unwind", 14) == 0)
307 me->arch.unwind_section = i;
309 if (sechdrs[i].sh_type != SHT_RELA)
312 /* some of these are not relevant for 32-bit/64-bit
313 * we leave them here to make the code common. the
314 * compiler will do its thing and optimize out the
315 * stuff we don't need
317 gots += count_gots(rels, nrels);
318 fdescs += count_fdescs(rels, nrels);
320 /* XXX: By sorting the relocs and finding duplicate entries
321 * we could reduce the number of necessary stubs and save
323 count = count_stubs(rels, nrels);
327 /* so we need relocation stubs. reserve necessary memory. */
328 /* sh_info gives the section for which we need to add stubs. */
329 s = sechdrs[i].sh_info;
331 /* each code section should only have one relocation section */
332 WARN_ON(me->arch.section[s].stub_entries);
334 /* store number of stubs we need for this section */
335 me->arch.section[s].stub_entries += count;
338 /* align things a bit */
339 me->core_size = ALIGN(me->core_size, 16);
340 me->arch.got_offset = me->core_size;
341 me->core_size += gots * sizeof(struct got_entry);
343 me->core_size = ALIGN(me->core_size, 16);
344 me->arch.fdesc_offset = me->core_size;
345 me->core_size += fdescs * sizeof(Elf_Fdesc);
347 me->arch.got_max = gots;
348 me->arch.fdesc_max = fdescs;
354 static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
357 struct got_entry *got;
363 got = me->module_core + me->arch.got_offset;
364 for (i = 0; got[i].addr; i++)
365 if (got[i].addr == value)
368 BUG_ON(++me->arch.got_count > me->arch.got_max);
372 DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
374 return i * sizeof(struct got_entry);
376 #endif /* CONFIG_64BIT */
379 static Elf_Addr get_fdesc(struct module *me, unsigned long value)
381 Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
384 printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
388 /* Look for existing fdesc entry. */
389 while (fdesc->addr) {
390 if (fdesc->addr == value)
391 return (Elf_Addr)fdesc;
395 BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
399 fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
400 return (Elf_Addr)fdesc;
402 #endif /* CONFIG_64BIT */
410 static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
411 enum elf_stub_type stub_type, Elf_Addr loc0, unsigned int targetsec)
413 struct stub_entry *stub;
415 /* initialize stub_offset to point in front of the section */
416 if (!me->arch.section[targetsec].stub_offset) {
417 loc0 -= (me->arch.section[targetsec].stub_entries + 1) *
418 sizeof(struct stub_entry);
419 /* get correct alignment for the stubs */
420 loc0 = ALIGN(loc0, sizeof(struct stub_entry));
421 me->arch.section[targetsec].stub_offset = loc0;
424 /* get address of stub entry */
425 stub = (void *) me->arch.section[targetsec].stub_offset;
426 me->arch.section[targetsec].stub_offset += sizeof(struct stub_entry);
428 /* do not write outside available stub area */
429 BUG_ON(0 == me->arch.section[targetsec].stub_entries--);
433 /* for 32-bit the stub looks like this:
435 * be,n R'XXX(%sr4,%r1)
437 //value = *(unsigned long *)((value + addend) & ~3); /* why? */
439 stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */
440 stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */
442 stub->insns[0] |= reassemble_21(lrsel(value, addend));
443 stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
446 /* for 64-bit we have three kinds of stubs:
447 * for normal function calls:
459 * for direct branches (jumps between different section of the
467 stub->insns[0] = 0x537b0000; /* ldd 0(%dp),%dp */
468 stub->insns[1] = 0x53610020; /* ldd 10(%dp),%r1 */
469 stub->insns[2] = 0xe820d000; /* bve (%r1) */
470 stub->insns[3] = 0x537b0030; /* ldd 18(%dp),%dp */
472 stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff);
475 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
476 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
477 stub->insns[2] = 0x50210020; /* ldd 10(%r1),%r1 */
478 stub->insns[3] = 0xe820d002; /* bve,n (%r1) */
480 stub->insns[0] |= reassemble_21(lrsel(value, addend));
481 stub->insns[1] |= reassemble_14(rrsel(value, addend));
483 case ELF_STUB_DIRECT:
484 stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
485 stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
486 stub->insns[2] = 0xe820d002; /* bve,n (%r1) */
488 stub->insns[0] |= reassemble_21(lrsel(value, addend));
489 stub->insns[1] |= reassemble_14(rrsel(value, addend));
495 return (Elf_Addr)stub;
498 int apply_relocate(Elf_Shdr *sechdrs,
500 unsigned int symindex,
504 /* parisc should not need this ... */
505 printk(KERN_ERR "module %s: RELOCATION unsupported\n",
511 int apply_relocate_add(Elf_Shdr *sechdrs,
513 unsigned int symindex,
518 Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
525 unsigned int targetsec = sechdrs[relsec].sh_info;
526 //unsigned long dp = (unsigned long)$global$;
527 register unsigned long dp asm ("r27");
529 DEBUGP("Applying relocate section %u to %u\n", relsec,
531 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
532 /* This is where to make the change */
533 loc = (void *)sechdrs[targetsec].sh_addr
535 /* This is the start of the target section */
536 loc0 = sechdrs[targetsec].sh_addr;
537 /* This is the symbol it is referring to */
538 sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
539 + ELF32_R_SYM(rel[i].r_info);
540 if (!sym->st_value) {
541 printk(KERN_WARNING "%s: Unknown symbol %s\n",
542 me->name, strtab + sym->st_name);
545 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
546 dot = (Elf32_Addr)loc & ~0x03;
549 addend = rel[i].r_addend;
552 #define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
553 DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
554 strtab + sym->st_name,
555 (uint32_t)loc, val, addend,
569 switch (ELF32_R_TYPE(rel[i].r_info)) {
570 case R_PARISC_PLABEL32:
571 /* 32-bit function address */
572 /* no function descriptors... */
573 *loc = fsel(val, addend);
576 /* direct 32-bit ref */
577 *loc = fsel(val, addend);
579 case R_PARISC_DIR21L:
580 /* left 21 bits of effective address */
581 val = lrsel(val, addend);
582 *loc = mask(*loc, 21) | reassemble_21(val);
584 case R_PARISC_DIR14R:
585 /* right 14 bits of effective address */
586 val = rrsel(val, addend);
587 *loc = mask(*loc, 14) | reassemble_14(val);
589 case R_PARISC_SEGREL32:
590 /* 32-bit segment relative address */
591 /* See note about special handling of SEGREL32 at
592 * the beginning of this file.
594 *loc = fsel(val, addend);
596 case R_PARISC_DPREL21L:
597 /* left 21 bit of relative address */
598 val = lrsel(val - dp, addend);
599 *loc = mask(*loc, 21) | reassemble_21(val);
601 case R_PARISC_DPREL14R:
602 /* right 14 bit of relative address */
603 val = rrsel(val - dp, addend);
604 *loc = mask(*loc, 14) | reassemble_14(val);
606 case R_PARISC_PCREL17F:
607 /* 17-bit PC relative address */
608 /* calculate direct call offset */
610 val = (val - dot - 8)/4;
611 if (!RELOC_REACHABLE(val, 17)) {
612 /* direct distance too far, create
613 * stub entry instead */
614 val = get_stub(me, sym->st_value, addend,
615 ELF_STUB_DIRECT, loc0, targetsec);
616 val = (val - dot - 8)/4;
617 CHECK_RELOC(val, 17);
619 *loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
621 case R_PARISC_PCREL22F:
622 /* 22-bit PC relative address; only defined for pa20 */
623 /* calculate direct call offset */
625 val = (val - dot - 8)/4;
626 if (!RELOC_REACHABLE(val, 22)) {
627 /* direct distance too far, create
628 * stub entry instead */
629 val = get_stub(me, sym->st_value, addend,
630 ELF_STUB_DIRECT, loc0, targetsec);
631 val = (val - dot - 8)/4;
632 CHECK_RELOC(val, 22);
634 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
638 printk(KERN_ERR "module %s: Unknown relocation: %u\n",
639 me->name, ELF32_R_TYPE(rel[i].r_info));
648 int apply_relocate_add(Elf_Shdr *sechdrs,
650 unsigned int symindex,
655 Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
663 unsigned int targetsec = sechdrs[relsec].sh_info;
665 DEBUGP("Applying relocate section %u to %u\n", relsec,
667 for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
668 /* This is where to make the change */
669 loc = (void *)sechdrs[targetsec].sh_addr
671 /* This is the start of the target section */
672 loc0 = sechdrs[targetsec].sh_addr;
673 /* This is the symbol it is referring to */
674 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
675 + ELF64_R_SYM(rel[i].r_info);
676 if (!sym->st_value) {
677 printk(KERN_WARNING "%s: Unknown symbol %s\n",
678 me->name, strtab + sym->st_name);
681 //dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
682 dot = (Elf64_Addr)loc & ~0x03;
683 loc64 = (Elf64_Xword *)loc;
686 addend = rel[i].r_addend;
689 #define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
690 printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
691 strtab + sym->st_name,
703 switch (ELF64_R_TYPE(rel[i].r_info)) {
704 case R_PARISC_LTOFF21L:
705 /* LT-relative; left 21 bits */
706 val = get_got(me, val, addend);
707 DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
708 strtab + sym->st_name,
711 *loc = mask(*loc, 21) | reassemble_21(val);
713 case R_PARISC_LTOFF14R:
714 /* L(ltoff(val+addend)) */
715 /* LT-relative; right 14 bits */
716 val = get_got(me, val, addend);
718 DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
719 strtab + sym->st_name,
721 *loc = mask(*loc, 14) | reassemble_14(val);
723 case R_PARISC_PCREL22F:
724 /* PC-relative; 22 bits */
725 DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
726 strtab + sym->st_name,
729 /* can we reach it locally? */
730 if (in_local(me, (void *)val)) {
731 /* this is the case where the symbol is local
732 * to the module, but in a different section,
733 * so stub the jump in case it's more than 22
735 val = (val - dot - 8)/4;
736 if (!RELOC_REACHABLE(val, 22)) {
737 /* direct distance too far, create
738 * stub entry instead */
739 val = get_stub(me, sym->st_value,
740 addend, ELF_STUB_DIRECT,
743 /* Ok, we can reach it directly. */
749 if (strncmp(strtab + sym->st_name, "$$", 2)
751 val = get_stub(me, val, addend, ELF_STUB_MILLI,
754 val = get_stub(me, val, addend, ELF_STUB_GOT,
757 DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n",
758 strtab + sym->st_name, loc, sym->st_value,
760 val = (val - dot - 8)/4;
761 CHECK_RELOC(val, 22);
762 *loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
765 /* 64-bit effective address */
766 *loc64 = val + addend;
768 case R_PARISC_SEGREL32:
769 /* 32-bit segment relative address */
770 /* See note about special handling of SEGREL32 at
771 * the beginning of this file.
773 *loc = fsel(val, addend);
775 case R_PARISC_FPTR64:
776 /* 64-bit function address */
777 if(in_local(me, (void *)(val + addend))) {
778 *loc64 = get_fdesc(me, val+addend);
779 DEBUGP("FDESC for %s at %p points to %lx\n",
780 strtab + sym->st_name, *loc64,
781 ((Elf_Fdesc *)*loc64)->addr);
783 /* if the symbol is not local to this
784 * module then val+addend is a pointer
785 * to the function descriptor */
786 DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
787 strtab + sym->st_name,
789 *loc64 = val + addend;
794 printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
795 me->name, ELF64_R_TYPE(rel[i].r_info));
804 register_unwind_table(struct module *me,
805 const Elf_Shdr *sechdrs)
807 unsigned char *table, *end;
810 if (!me->arch.unwind_section)
813 table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
814 end = table + sechdrs[me->arch.unwind_section].sh_size;
815 gp = (Elf_Addr)me->module_core + me->arch.got_offset;
817 DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
818 me->arch.unwind_section, table, end, gp);
819 me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
823 deregister_unwind_table(struct module *me)
826 unwind_table_remove(me->arch.unwind);
829 int module_finalize(const Elf_Ehdr *hdr,
830 const Elf_Shdr *sechdrs,
835 const char *strtab = NULL;
836 Elf_Sym *newptr, *oldptr;
837 Elf_Shdr *symhdr = NULL;
842 entry = (Elf_Fdesc *)me->init;
843 printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
844 entry->gp, entry->addr);
845 addr = (u32 *)entry->addr;
846 printk("INSNS: %x %x %x %x\n",
847 addr[0], addr[1], addr[2], addr[3]);
848 printk("got entries used %ld, gots max %ld\n"
849 "fdescs used %ld, fdescs max %ld\n",
850 me->arch.got_count, me->arch.got_max,
851 me->arch.fdesc_count, me->arch.fdesc_max);
854 register_unwind_table(me, sechdrs);
856 /* haven't filled in me->symtab yet, so have to find it
858 for (i = 1; i < hdr->e_shnum; i++) {
859 if(sechdrs[i].sh_type == SHT_SYMTAB
860 && (sechdrs[i].sh_type & SHF_ALLOC)) {
861 int strindex = sechdrs[i].sh_link;
863 * The cast is to drop the const from
864 * the sechdrs pointer */
865 symhdr = (Elf_Shdr *)&sechdrs[i];
866 strtab = (char *)sechdrs[strindex].sh_addr;
871 DEBUGP("module %s: strtab %p, symhdr %p\n",
872 me->name, strtab, symhdr);
874 if(me->arch.got_count > MAX_GOTS) {
875 printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d)\n",
876 me->name, me->arch.got_count, MAX_GOTS);
880 kfree(me->arch.section);
881 me->arch.section = NULL;
883 /* no symbol table */
887 oldptr = (void *)symhdr->sh_addr;
888 newptr = oldptr + 1; /* we start counting at 1 */
889 nsyms = symhdr->sh_size / sizeof(Elf_Sym);
890 DEBUGP("OLD num_symtab %lu\n", nsyms);
892 for (i = 1; i < nsyms; i++) {
893 oldptr++; /* note, count starts at 1 so preincrement */
894 if(strncmp(strtab + oldptr->st_name,
904 nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
905 DEBUGP("NEW num_symtab %lu\n", nsyms);
906 symhdr->sh_size = nsyms * sizeof(Elf_Sym);
907 return module_bug_finalize(hdr, sechdrs, me);
910 void module_arch_cleanup(struct module *mod)
912 deregister_unwind_table(mod);
913 module_bug_cleanup(mod);
917 void *dereference_function_descriptor(void *ptr)
919 Elf64_Fdesc *desc = ptr;
922 if (!probe_kernel_address(&desc->addr, p))