MN10300: Add support for new ELF relocs in kernel modules
Add support for new relocs which may show up in MN10300 kernel modules due to
linker relaxation.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/mn10300/include/asm/elf.h b/arch/mn10300/include/asm/elf.h
index 4910546..75a70aa 100644
--- a/arch/mn10300/include/asm/elf.h
+++ b/arch/mn10300/include/asm/elf.h
@@ -28,6 +28,8 @@
#define R_MN10300_PCREL8 6 /* PC-relative 8-bit signed. */
#define R_MN10300_24 9 /* Direct 24 bit. */
#define R_MN10300_RELATIVE 23 /* Adjust by program base. */
+#define R_MN10300_SYM_DIFF 33 /* Adjustment when relaxing. */
+#define R_MN10300_ALIGN 34 /* Alignment requirement. */
/*
* ELF register definitions..
diff --git a/arch/mn10300/kernel/module.c b/arch/mn10300/kernel/module.c
index 4fa0e36..6aea7fd 100644
--- a/arch/mn10300/kernel/module.c
+++ b/arch/mn10300/kernel/module.c
@@ -1,6 +1,6 @@
/* MN10300 Kernel module helper routines
*
- * Copyright (C) 2007, 2008 Red Hat, Inc. All Rights Reserved.
+ * Copyright (C) 2007, 2008, 2009 Red Hat, Inc. All Rights Reserved.
* Written by Mark Salter (msalter@redhat.com)
* - Derived from arch/i386/kernel/module.c
*
@@ -103,10 +103,10 @@
unsigned int relsec,
struct module *me)
{
- unsigned int i;
+ unsigned int i, sym_diff_seen = 0;
Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
Elf32_Sym *sym;
- Elf32_Addr relocation;
+ Elf32_Addr relocation, sym_diff_val = 0;
uint8_t *location;
uint32_t value;
@@ -126,6 +126,22 @@
/* this is the adjustment to be made */
relocation = sym->st_value + rel[i].r_addend;
+ if (sym_diff_seen) {
+ switch (ELF32_R_TYPE(rel[i].r_info)) {
+ case R_MN10300_32:
+ case R_MN10300_24:
+ case R_MN10300_16:
+ case R_MN10300_8:
+ relocation -= sym_diff_val;
+ sym_diff_seen = 0;
+ break;
+ default:
+ printk(KERN_ERR "module %s: Unexpected SYM_DIFF relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
+ }
+
switch (ELF32_R_TYPE(rel[i].r_info)) {
/* for the first four relocation types, we simply
* store the adjustment at the location given */
@@ -157,12 +173,29 @@
*location = relocation - (uint32_t) location;
break;
+ case R_MN10300_SYM_DIFF:
+ /* This is used to adjust the next reloc as required
+ * by relaxation. */
+ sym_diff_seen = 1;
+ sym_diff_val = sym->st_value;
+ break;
+
+ case R_MN10300_ALIGN:
+ /* Just ignore the ALIGN relocs.
+ * Only interesting if kernel performed relaxation. */
+ continue;
+
default:
printk(KERN_ERR "module %s: Unknown relocation: %u\n",
me->name, ELF32_R_TYPE(rel[i].r_info));
return -ENOEXEC;
}
}
+ if (sym_diff_seen) {
+ printk(KERN_ERR "module %s: Nothing follows SYM_DIFF relocation: %u\n",
+ me->name, ELF32_R_TYPE(rel[i].r_info));
+ return -ENOEXEC;
+ }
return 0;
}