Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 boot and percpu updates from Ingo Molnar:
 "This tree contains a bootable images documentation update plus three
  slightly misplaced x86/asm percpu changes/optimizations"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86-64: Use RIP-relative addressing for most per-CPU accesses
  x86-64: Handle PC-relative relocations on per-CPU data
  x86: Convert a few more per-CPU items to read-mostly ones
  x86, boot: Document intermediates more clearly

1 files changed, 27 insertions, 9 deletions

diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index a5efb21d522..0c2fae8d929 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -20,7 +20,10 @@ struct relocs {
 
 static struct relocs relocs16;
 static struct relocs relocs32;
+#if ELF_BITS == 64
+static struct relocs relocs32neg;
 static struct relocs relocs64;
+#endif
 
 struct section {
 	Elf_Shdr       shdr;
@@ -762,11 +765,16 @@ static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
 
 	switch (r_type) {
 	case R_X86_64_NONE:
+		/* NONE can be ignored. */
+		break;
+
 	case R_X86_64_PC32:
 		/*
-		 * NONE can be ignored and PC relative relocations don't
-		 * need to be adjusted.
+		 * PC relative relocations don't need to be adjusted unless
+		 * referencing a percpu symbol.
 		 */
+		if (is_percpu_sym(sym, symname))
+			add_reloc(&relocs32neg, offset);
 		break;
 
 	case R_X86_64_32:
@@ -986,7 +994,10 @@ static void emit_relocs(int as_text, int use_real_mode)
 	/* Order the relocations for more efficient processing */
 	sort_relocs(&relocs16);
 	sort_relocs(&relocs32);
+#if ELF_BITS == 64
+	sort_relocs(&relocs32neg);
 	sort_relocs(&relocs64);
+#endif
 
 	/* Print the relocations */
 	if (as_text) {
@@ -1007,14 +1018,21 @@ static void emit_relocs(int as_text, int use_real_mode)
 		for (i = 0; i < relocs32.count; i++)
 			write_reloc(relocs32.offset[i], stdout);
 	} else {
-		if (ELF_BITS == 64) {
-			/* Print a stop */
-			write_reloc(0, stdout);
+#if ELF_BITS == 64
+		/* Print a stop */
+		write_reloc(0, stdout);
 
-			/* Now print each relocation */
-			for (i = 0; i < relocs64.count; i++)
-				write_reloc(relocs64.offset[i], stdout);
-		}
+		/* Now print each relocation */
+		for (i = 0; i < relocs64.count; i++)
+			write_reloc(relocs64.offset[i], stdout);
+
+		/* Print a stop */
+		write_reloc(0, stdout);
+
+		/* Now print each inverse 32-bit relocation */
+		for (i = 0; i < relocs32neg.count; i++)
+			write_reloc(relocs32neg.offset[i], stdout);
+#endif
 
 		/* Print a stop */
 		write_reloc(0, stdout);