x86: move stack_canary into irq_stack

[pandora-kernel.git] / arch / x86 / kernel / head_64.S

diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 98ea26a..a0a2b5c 100644 (file)
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -242,13 +242,10 @@ ENTRY(secondary_startup_64)
 
        /* Set up %gs.
         *
-        * On SMP, %gs should point to the per-cpu area.  For initial
-        * boot, make %gs point to the init data section.  For a
-        * secondary CPU,initial_gs should be set to its pda address
-        * before the CPU runs this code.
-        *
-        * On UP, initial_gs points to PER_CPU_VAR(__pda) and doesn't
-        * change.
+        * The base of %gs always points to the bottom of the irqstack
+        * union.  If the stack protector canary is enabled, it is
+        * located at %gs:40.  Note that, on SMP, the boot cpu uses
+        * init data section till per cpu areas are set up.
         */
        movl    $MSR_GS_BASE,%ecx
        movq    initial_gs(%rip),%rax
@@ -281,7 +278,7 @@ ENTRY(secondary_startup_64)
 #ifdef CONFIG_SMP
        .quad   __per_cpu_load
 #else
-       .quad   PER_CPU_VAR(__pda)
+       .quad   PER_CPU_VAR(irq_stack_union)
 #endif
        __FINITDATA