arm64: Add support for relocations needed for linaro gcc

grub-core/kern/arm64/dl.c

@@ -132,6 +132,12 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
 	    *abs_place = (grub_uint64_t) sym_addr;
 	  }
 	  break;
+	case R_AARCH64_ADD_ABS_LO12_NC:
+	  grub_arm64_set_abs_lo12 (place, sym_addr);
+	  break;
+	case R_AARCH64_LDST64_ABS_LO12_NC:
+	  grub_arm64_set_abs_lo12_ldst64 (place, sym_addr);
+	  break;
 	case R_AARCH64_CALL26:
 	case R_AARCH64_JUMP26:
 	  {
@@ -154,6 +160,18 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
 	    grub_arm64_set_xxxx26_offset (place, offset);
 	  }
 	  break;
+	case R_AARCH64_ADR_PREL_PG_HI21:
+	  {
+	    grub_int64_t offset = (sym_addr & ~0xfffULL) - (((grub_uint64_t) place) & ~0xfffULL);
+
+	    if (!grub_arm64_check_hi21_signed (offset))
+		return grub_error (GRUB_ERR_BAD_MODULE,
+				   "HI21 out of range");
+
+	    grub_arm64_set_hi21 (place, offset);
+	  }
+	  break;
+
 	default:
 	  return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
 			     N_("relocation 0x%x is not implemented yet"),

grub-core/kern/arm64/dl_helper.c

@@ -53,3 +53,43 @@ grub_arm64_set_xxxx26_offset (grub_uint32_t *place, grub_int64_t offset)
   *place &= insmask;
   *place |= grub_cpu_to_le32 (offset >> 2) & ~insmask;
 }
+
+int
+grub_arm64_check_hi21_signed (grub_int64_t offset)
+{
+  if (offset != (grub_int64_t)(grub_int32_t)offset)
+    return 0;
+  return 1;
+}
+
+void
+grub_arm64_set_hi21 (grub_uint32_t *place, grub_int64_t offset)
+{
+  const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0x9f00001f);
+  grub_uint32_t val;
+
+  offset >>= 12;
+  
+  val = ((offset & 3) << 29) | (((offset >> 2) & 0x7ffff) << 5);
+  
+  *place &= insmask;
+  *place |= grub_cpu_to_le32 (val) & ~insmask;
+}
+
+void
+grub_arm64_set_abs_lo12 (grub_uint32_t *place, grub_int64_t target)
+{
+  const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xffc003ff);
+
+  *place &= insmask;
+  *place |= grub_cpu_to_le32 (target << 10) & ~insmask;
+}
+
+void
+grub_arm64_set_abs_lo12_ldst64 (grub_uint32_t *place, grub_int64_t target)
+{
+  const grub_uint32_t insmask = grub_cpu_to_le32_compile_time (0xfff803ff);
+
+  *place &= insmask;
+  *place |= grub_cpu_to_le32 (target << 7) & ~insmask;
+}

include/grub/arm64/reloc.h

@@ -22,5 +22,13 @@
 int grub_arm_64_check_xxxx26_offset (grub_int64_t offset);
 void
 grub_arm64_set_xxxx26_offset (grub_uint32_t *place, grub_int64_t offset);
+int
+grub_arm64_check_hi21_signed (grub_int64_t offset);
+void
+grub_arm64_set_hi21 (grub_uint32_t *place, grub_int64_t offset);
+void
+grub_arm64_set_abs_lo12 (grub_uint32_t *place, grub_int64_t target);
+void
+grub_arm64_set_abs_lo12_ldst64 (grub_uint32_t *place, grub_int64_t target);
 
 #endif

include/grub/elf.h

@@ -2068,6 +2068,9 @@ typedef Elf32_Addr Elf32_Conflict;
 #define R_AARCH64_NONE			0	/* No relocation.  */
 #define R_AARCH64_ABS64			257	/* Direct 64 bit. */
 #define R_AARCH64_ABS32			258	/* Direct 32 bit.  */
+#define R_AARCH64_ADR_PREL_PG_HI21	275
+#define R_AARCH64_ADD_ABS_LO12_NC	277
+#define R_AARCH64_LDST64_ABS_LO12_NC	286
 #define R_AARCH64_JUMP26		282	/* 26-bit relative. */
 #define R_AARCH64_CALL26		283	/* 26-bit relative. */
 #define R_AARCH64_COPY			1024	/* Copy symbol at runtime.  */

util/grub-mkimagexx.c

@@ -836,6 +836,14 @@ SUFFIX (relocate_addresses) (Elf_Ehdr *e, Elf_Shdr *sections,
 		       *target = grub_host_to_target64 (grub_target_to_host64 (*target) + sym_addr);
 		     }
 		     break;
+		   case R_AARCH64_ADD_ABS_LO12_NC:
+		     grub_arm64_set_abs_lo12 ((grub_uint32_t *) target,
+					      sym_addr);
+		     break;
+		   case R_AARCH64_LDST64_ABS_LO12_NC:
+		     grub_arm64_set_abs_lo12_ldst64 ((grub_uint32_t *) target,
+						     sym_addr);
+		     break;
 		   case R_AARCH64_JUMP26:
 		   case R_AARCH64_CALL26:
 		     {
@@ -848,6 +856,17 @@ SUFFIX (relocate_addresses) (Elf_Ehdr *e, Elf_Shdr *sections,
 						     sym_addr);
 		     }
 		     break;
+		   case R_AARCH64_ADR_PREL_PG_HI21:
+		     {
+		       sym_addr &= ~0xfffULL;
+		       sym_addr -= (offset + SUFFIX (entry_point)) & ~0xfffULL;
+		       if (!grub_arm64_check_hi21_signed (sym_addr))
+			 grub_util_error ("%s", "CALL26 Relocation out of range");
+
+		       grub_arm64_set_hi21((grub_uint32_t *)target,
+					   sym_addr);
+		     }
+		     break;
 		   default:
 		     grub_util_error (_("relocation 0x%x is not implemented yet"),
 				      (unsigned int) ELF_R_TYPE (info));
@@ -1200,6 +1219,15 @@ SUFFIX (make_reloc_section) (Elf_Ehdr *e, void **out,
 		  case R_AARCH64_CALL26:
 		  case R_AARCH64_JUMP26:
 		    break;
+		    /* Page-relative relocations do not require fixup entries. */
+		  case R_AARCH64_ADR_PREL_PG_HI21:
+		     /* We page-align the whole kernel, so no need
+			for fixup entries.
+		      */
+		  case R_AARCH64_ADD_ABS_LO12_NC:
+		  case R_AARCH64_LDST64_ABS_LO12_NC:
+		    break;
+
 		  default:
 		    grub_util_error (_("relocation 0x%x is not implemented yet"),
 				     (unsigned int) ELF_R_TYPE (info));
@@ -1343,6 +1371,9 @@ SUFFIX (locate_sections) (const char *kernel_path,
   Elf_Shdr *s;
 
   *all_align = 1;
+  /* Page-aligning simplifies relocation handling.  */
+  if (image_target->elf_target == EM_AARCH64)
+    *all_align = 4096;
 
   section_addresses = xmalloc (sizeof (*section_addresses) * num_sections);
   memset (section_addresses, 0, sizeof (*section_addresses) * num_sections);

util/grub-module-verifier.c

@@ -107,7 +107,13 @@ struct grub_module_verifier_arch archs[] = {
       R_AARCH64_CALL26,
       R_AARCH64_JUMP26,
       -1
-    } },
+    }, (int[]){
+      R_AARCH64_ADR_PREL_PG_HI21,
+      R_AARCH64_ADD_ABS_LO12_NC,
+      R_AARCH64_LDST64_ABS_LO12_NC,
+      -1
+    }
+  },
 };