[PATCH] ia64: force all kernel sections into one and the same segment

Older versions of the linker do not handle cross-segment segment-relative
relocations properly.  This becomes a real problem when the linker decides
to put .text and .text.init into different segments (for whatever reasons)
because in that case, broken linkers will produce a broken unwind section,
which can cause nasty Heisenbugs, where, for example, unwinding may or may
not work depending on the exact value of the IP in a function.

arch/ia64/kernel/vmlinux.lds.S

@@ -12,6 +12,11 @@ OUTPUT_FORMAT("elf64-ia64-little")
 OUTPUT_ARCH(ia64)
 ENTRY(phys_start)
 jiffies = jiffies_64;
+PHDRS {
+  code   PT_LOAD;
+  percpu PT_LOAD;
+  data   PT_LOAD;
+}
 SECTIONS
 {
   /* Sections to be discarded */
@@ -26,6 +31,7 @@ SECTIONS
   v = PAGE_OFFSET;	/* this symbol is here to make debugging easier... */
   phys_start = _start - LOAD_OFFSET;
 
+  code : { } :code
   . = KERNEL_START;
 
   _text = .;
@@ -173,6 +179,7 @@ SECTIONS
         { *(.data.cacheline_aligned) }
 
   /* Per-cpu data: */
+  percpu : { } :percpu
   . = ALIGN(PERCPU_PAGE_SIZE);
   __phys_per_cpu_start = .;
   .data.percpu PERCPU_ADDR : AT(__phys_per_cpu_start - LOAD_OFFSET)
@@ -183,6 +190,7 @@ SECTIONS
 	}
   . = __phys_per_cpu_start + PERCPU_PAGE_SIZE;	/* ensure percpu data fits into percpu page size */
 
+  data : { } :data
   .data : AT(ADDR(.data) - LOAD_OFFSET)
 	{ *(.data) *(.data1) *(.gnu.linkonce.d*) CONSTRUCTORS }
 
@@ -205,6 +213,7 @@ SECTIONS
 
   _end = .;
 
+  code : { } :code
   /* Stabs debugging sections.  */
   .stab 0 : { *(.stab) }
   .stabstr 0 : { *(.stabstr) }