1 files changed, 88 insertions, 0 deletions

diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
index dab48f27263f..bac03c81489d 100644
--- a/arch/arm/kernel/module.c
+++ b/arch/arm/kernel/module.c
@@ -22,6 +22,7 @@
 
 #include <asm/pgtable.h>
 #include <asm/sections.h>
+#include <asm/unwind.h>
 
 #ifdef CONFIG_XIP_KERNEL
 /*
@@ -66,6 +67,24 @@ int module_frob_arch_sections(Elf_Ehdr *hdr,
                               char *secstrings,
                               struct module *mod)
 {
+#ifdef CONFIG_ARM_UNWIND
+        Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
+
+        for (s = sechdrs; s < sechdrs_end; s++) {
+                if (strcmp(".ARM.exidx.init.text", secstrings + s->sh_name) == 0)
+                        mod->arch.unw_sec_init = s;
+                else if (strcmp(".ARM.exidx.devinit.text", secstrings + s->sh_name) == 0)
+                        mod->arch.unw_sec_devinit = s;
+                else if (strcmp(".ARM.exidx", secstrings + s->sh_name) == 0)
+                        mod->arch.unw_sec_core = s;
+                else if (strcmp(".init.text", secstrings + s->sh_name) == 0)
+                        mod->arch.sec_init_text = s;
+                else if (strcmp(".devinit.text", secstrings + s->sh_name) == 0)
+                        mod->arch.sec_devinit_text = s;
+                else if (strcmp(".text", secstrings + s->sh_name) == 0)
+                        mod->arch.sec_core_text = s;
+        }
+#endif
         return 0;
 }
 
@@ -104,6 +123,10 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
                 loc = dstsec->sh_addr + rel->r_offset;
 
                 switch (ELF32_R_TYPE(rel->r_info)) {
+                case R_ARM_NONE:
+                        /* ignore */
+                        break;
+
                 case R_ARM_ABS32:
                         *(u32 *)loc += sym->st_value;
                         break;
@@ -132,6 +155,35 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
                         *(u32 *)loc |= offset & 0x00ffffff;
                         break;
 
+               case R_ARM_V4BX:
+                       /* Preserve Rm and the condition code. Alter
+                        * other bits to re-code instruction as
+                        * MOV PC,Rm.
+                        */
+                       *(u32 *)loc &= 0xf000000f;
+                       *(u32 *)loc |= 0x01a0f000;
+                       break;
+
+                case R_ARM_PREL31:
+                        offset = *(u32 *)loc + sym->st_value - loc;
+                        *(u32 *)loc = offset & 0x7fffffff;
+                        break;
+
+                case R_ARM_MOVW_ABS_NC:
+                case R_ARM_MOVT_ABS:
+                        offset = *(u32 *)loc;
+                        offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
+                        offset = (offset ^ 0x8000) - 0x8000;
+
+                        offset += sym->st_value;
+                        if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
+                                offset >>= 16;
+
+                        *(u32 *)loc &= 0xfff0f000;
+                        *(u32 *)loc |= ((offset & 0xf000) << 4) |
+                                        (offset & 0x0fff);
+                        break;
+
                 default:
                         printk(KERN_ERR "%s: unknown relocation: %u\n",
                                module->name, ELF32_R_TYPE(rel->r_info));
@@ -150,14 +202,50 @@ apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
         return -ENOEXEC;
 }
 
+#ifdef CONFIG_ARM_UNWIND
+static void register_unwind_tables(struct module *mod)
+{
+        if (mod->arch.unw_sec_init && mod->arch.sec_init_text)
+                mod->arch.unwind_init =
+                        unwind_table_add(mod->arch.unw_sec_init->sh_addr,
+                                         mod->arch.unw_sec_init->sh_size,
+                                         mod->arch.sec_init_text->sh_addr,
+                                         mod->arch.sec_init_text->sh_size);
+        if (mod->arch.unw_sec_devinit && mod->arch.sec_devinit_text)
+                mod->arch.unwind_devinit =
+                        unwind_table_add(mod->arch.unw_sec_devinit->sh_addr,
+                                         mod->arch.unw_sec_devinit->sh_size,
+                                         mod->arch.sec_devinit_text->sh_addr,
+                                         mod->arch.sec_devinit_text->sh_size);
+        if (mod->arch.unw_sec_core && mod->arch.sec_core_text)
+                mod->arch.unwind_core =
+                        unwind_table_add(mod->arch.unw_sec_core->sh_addr,
+                                         mod->arch.unw_sec_core->sh_size,
+                                         mod->arch.sec_core_text->sh_addr,
+                                         mod->arch.sec_core_text->sh_size);
+}
+
+static void unregister_unwind_tables(struct module *mod)
+{
+        unwind_table_del(mod->arch.unwind_init);
+        unwind_table_del(mod->arch.unwind_devinit);
+        unwind_table_del(mod->arch.unwind_core);
+}
+#else
+static inline void register_unwind_tables(struct module *mod) { }
+static inline void unregister_unwind_tables(struct module *mod) { }
+#endif
+
 int
 module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
                 struct module *module)
 {
+        register_unwind_tables(module);
         return 0;
 }
 
 void
 module_arch_cleanup(struct module *mod)
 {
+        unregister_unwind_tables(mod);
 }