1 files changed, 24 insertions, 2 deletions

diff --git a/arch/x86/kernel/vmlinux_64.lds.S b/arch/x86/kernel/vmlinux_64.lds.S
index 1a614c0e6bef..c9740996430a 100644
--- a/arch/x86/kernel/vmlinux_64.lds.S
+++ b/arch/x86/kernel/vmlinux_64.lds.S
@@ -5,6 +5,7 @@
 #define LOAD_OFFSET __START_KERNEL_map
 
 #include <asm-generic/vmlinux.lds.h>
+#include <asm/asm-offsets.h>
 #include <asm/page.h>
 
 #undef i386     /* in case the preprocessor is a 32bit one */
@@ -13,12 +14,14 @@ OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64")
 OUTPUT_ARCH(i386:x86-64)
 ENTRY(phys_startup_64)
 jiffies_64 = jiffies;
-_proxy_pda = 1;
 PHDRS {
         text PT_LOAD FLAGS(5);  /* R_E */
         data PT_LOAD FLAGS(7);  /* RWE */
         user PT_LOAD FLAGS(7);  /* RWE */
         data.init PT_LOAD FLAGS(7);     /* RWE */
+#ifdef CONFIG_SMP
+        percpu PT_LOAD FLAGS(7);        /* RWE */
+#endif
         note PT_NOTE FLAGS(0);  /* ___ */
 }
 SECTIONS
@@ -208,14 +211,28 @@ SECTIONS
   __initramfs_end = .;
 #endif
 
+#ifdef CONFIG_SMP
+  /*
+   * percpu offsets are zero-based on SMP.  PERCPU_VADDR() changes the
+   * output PHDR, so the next output section - __data_nosave - should
+   * switch it back to data.init.  Also, pda should be at the head of
+   * percpu area.  Preallocate it and define the percpu offset symbol
+   * so that it can be accessed as a percpu variable.
+   */
+  . = ALIGN(PAGE_SIZE);
+  PERCPU_VADDR(0, :percpu)
+#else
   PERCPU(PAGE_SIZE)
+#endif
 
   . = ALIGN(PAGE_SIZE);
   __init_end = .;
 
   . = ALIGN(PAGE_SIZE);
   __nosave_begin = .;
-  .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) { *(.data.nosave) }
+  .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
+      *(.data.nosave)
+  } :data.init  /* switch back to data.init, see PERCPU_VADDR() above */
   . = ALIGN(PAGE_SIZE);
   __nosave_end = .;
 
@@ -244,3 +261,8 @@ SECTIONS
  */
 ASSERT((_end - _text <= KERNEL_IMAGE_SIZE),
         "kernel image bigger than KERNEL_IMAGE_SIZE")
+
+#ifdef CONFIG_SMP
+ASSERT((per_cpu__irq_stack_union == 0),
+        "irq_stack_union is not at start of per-cpu area");
+#endif