x86, realmode: fix 64-bit wakeup sequence

There were number of issues in wakeup sequence:

- Wakeup stack was placed in hardcoded address.
- NX bit in EFER was not enabled.
- Initialization incorrectly set physical address
of secondary_startup_64.
- Some alignment issues.

This patch fixes these issues and in addition:

- Unifies coding conventions in .S files.
- Sets alignments of code and data right.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-18-git-send-email-jarkko.sakkinen@intel.com
Originally-by: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Len Brown <len.brown@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

8 files changed, 109 insertions, 106 deletions

diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 2423142b4da4..c2c27a41ab8f 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -13,6 +13,7 @@ always := realmode.bin
 
 realmode-y                      += header.o
 realmode-y                      += trampoline_$(BITS).o
+realmode-y                      += stack.o
 realmode-$(CONFIG_X86_32)       += reboot_32.o
 realmode-$(CONFIG_ACPI_SLEEP)   += wakeup/wakeup.o
 
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S
index 730b1316c099..a91ec8f6b15f 100644
--- a/arch/x86/realmode/rm/header.S
+++ b/arch/x86/realmode/rm/header.S
@@ -9,7 +9,7 @@
 
                 .section ".header", "a"
 
-ENTRY(real_mode_header)
+GLOBAL(real_mode_header)
                 .long   pa_text_start
                 .long   pa_ro_end
                 .long   pa_end
diff --git a/arch/x86/realmode/rm/reboot_32.S b/arch/x86/realmode/rm/reboot_32.S
index 50ba994ba921..8d9bfd13a93e 100644
--- a/arch/x86/realmode/rm/reboot_32.S
+++ b/arch/x86/realmode/rm/reboot_32.S
@@ -16,10 +16,9 @@
  */
         .section ".text32", "ax"
         .code32
-        .globl machine_real_restart_asm
 
-        .balign 16
-machine_real_restart_asm:
+        .balign 16
+ENTRY(machine_real_restart_asm)
         /* Set up the IDT for real mode. */
         lidtl   pa_machine_real_restart_idt
 
@@ -67,7 +66,7 @@ machine_real_restart_asm:
         .text
         .code16
 
-        .balign 16
+        .balign 16
 machine_real_restart_asm16:
 1:
         xorl    %ecx, %ecx
@@ -102,15 +101,15 @@ bios:
         ljmpw   $0xf000, $0xfff0
 
         .section ".rodata", "a"
-        .globl  machine_real_restart_idt, machine_real_restart_gdt
 
-        .balign 16
-machine_real_restart_idt:
+        .balign 16
+GLOBAL(machine_real_restart_idt)
         .word   0xffff          /* Length - real mode default value */
         .long   0               /* Base - real mode default value */
+END(machine_real_restart_idt)
 
-        .balign 16
-machine_real_restart_gdt:
+        .balign 16
+GLOBAL(machine_real_restart_gdt)
         /* Self-pointer */
         .word   0xffff          /* Length - real mode default value */
         .long   pa_machine_real_restart_gdt
@@ -130,3 +129,4 @@ machine_real_restart_gdt:
          * semantics we don't have to reload the segments once CR0.PE = 0.
          */
         .quad   GDT_ENTRY(0x0093, 0x100, 0xffff)
+END(machine_real_restart_gdt)
diff --git a/arch/x86/realmode/rm/stack.S b/arch/x86/realmode/rm/stack.S
new file mode 100644
index 000000000000..867ae87adfae
--- /dev/null
+++ b/arch/x86/realmode/rm/stack.S
@@ -0,0 +1,19 @@
+/*
+ * Common heap and stack allocations
+ */
+
+#include <linux/linkage.h>
+
+        .data
+GLOBAL(HEAP)
+        .long   rm_heap
+GLOBAL(heap_end)
+        .long   rm_stack
+
+        .bss
+        .balign 16
+GLOBAL(rm_heap)
+        .space  2048
+GLOBAL(rm_stack)
+        .space  2048
+GLOBAL(rm_stack_end)
diff --git a/arch/x86/realmode/rm/trampoline_32.S b/arch/x86/realmode/rm/trampoline_32.S
index 279f82ef7a9e..1ecdbb59191b 100644
--- a/arch/x86/realmode/rm/trampoline_32.S
+++ b/arch/x86/realmode/rm/trampoline_32.S
@@ -33,10 +33,9 @@
 
         .text
         .code16
-        .globl trampoline_data
 
-        .balign PAGE_SIZE
-trampoline_data:
+        .balign PAGE_SIZE
+ENTRY(trampoline_data)
         wbinvd                  # Needed for NUMA-Q should be harmless for others
 
         LJMPW_RM(1f)
@@ -70,20 +69,22 @@ trampoline_data:
 ENTRY(startup_32)                       # note: also used from wakeup_asm.S
         jmp     *%eax
 
-        .data
-        .globl startup_32_smp, boot_gdt, trampoline_status
-        .balign 4
-boot_gdt_descr:
-        .word   __BOOT_DS + 7                   # gdt limit
-boot_gdt:
-        .long   0                               # gdt base
+        .section ".rodata","a"
 
+        .balign 4
 boot_idt_descr:
         .word   0                               # idt limit = 0
         .long   0                               # idt base = 0L
 
-trampoline_status:
-        .long   0
+        .data
 
-startup_32_smp:
-        .long   0
+boot_gdt_descr:
+        .word   __BOOT_DS + 7                   # gdt limit
+GLOBAL(boot_gdt)
+        .long   0                               # gdt base
+
+        .bss
+
+        .balign 4
+GLOBAL(trampoline_status)       .space  4
+GLOBAL(startup_32_smp)          .space  4
diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S
index 7459c52f0c25..f71ea0800d3d 100644
--- a/arch/x86/realmode/rm/trampoline_64.S
+++ b/arch/x86/realmode/rm/trampoline_64.S
@@ -52,7 +52,7 @@ ENTRY(trampoline_data)
         # write marker for master knows we're running
 
         # Setup stack
-        movw    $trampoline_stack_end, %sp
+        movl    $rm_stack_end, %esp
 
         call    verify_cpu              # Verify the cpu supports long mode
         testl   %eax, %eax              # Check for return code
@@ -68,8 +68,11 @@ ENTRY(trampoline_data)
         lidtl   tidt    # load idt with 0, 0
         lgdtl   tgdt    # load gdt with whatever is appropriate
 
-        mov     $X86_CR0_PE, %ax        # protected mode (PE) bit
-        lmsw    %ax                     # into protected mode
+        movw    $__KERNEL_DS, %dx       # Data segment descriptor
+
+        # Enable protected mode
+        movl    $X86_CR0_PE, %eax       # protected mode (PE) bit
+        movl    %eax, %cr0              # into protected mode
 
         # flush prefetch and jump to startup_32
         ljmpl   $__KERNEL32_CS, $pa_startup_32
@@ -83,27 +86,27 @@ no_longmode:
         .code32
         .balign 4
 ENTRY(startup_32)
-        movl    $__KERNEL_DS, %eax      # Initialize the %ds segment register
-        movl    %eax, %ds
+        movl    %edx, %ss
+        addl    $pa_real_mode_base, %esp
+        movl    %edx, %ds
+        movl    %edx, %es
+        movl    %edx, %fs
+        movl    %edx, %gs
 
         movl    $X86_CR4_PAE, %eax
         movl    %eax, %cr4              # Enable PAE mode
 
-        movl    pa_startup_64_smp, %esi
-        movl    pa_startup_64_smp_high, %edi
-
-                                        # Setup trampoline 4 level pagetables
-        leal    pa_trampoline_level4_pgt, %eax
+        # Setup trampoline 4 level pagetables
+        movl    $pa_level3_ident_pgt, %eax
         movl    %eax, %cr3
 
         movl    $MSR_EFER, %ecx
-        movl    $(1 << _EFER_LME), %eax # Enable Long Mode
+        movl    $((1 << _EFER_LME) | (1 << _EFER_NX)), %eax     # Enable Long Mode
         xorl    %edx, %edx
         wrmsr
 
         # Enable paging and in turn activate Long Mode
-        # Enable protected mode
-        movl    $(X86_CR0_PG | X86_CR0_PE), %eax
+        movl    $(X86_CR0_PG | X86_CR0_WP | X86_CR0_PE), %eax
         movl    %eax, %cr0
 
         /*
@@ -119,10 +122,7 @@ ENTRY(startup_32)
         .balign 4
 ENTRY(startup_64)
         # Now jump into the kernel using virtual addresses
-        movl    %edi, %eax
-        shlq    $32, %rax
-        addl    %esi, %eax
-        jmp     *%rax
+        jmpq    *startup_64_smp(%rip)
 
         .section ".rodata","a"
         .balign 16
@@ -132,10 +132,10 @@ tidt:
 
         # Duplicate the global descriptor table
         # so the kernel can live anywhere
-        .balign 4
+        .balign 16
         .globl tgdt
 tgdt:
-        .short  tgdt_end - tgdt         # gdt limit
+        .short  tgdt_end - tgdt - 1     # gdt limit
         .long   pa_tgdt
         .short  0
         .quad   0x00cf9b000000ffff      # __KERNEL32_CS
@@ -143,23 +143,12 @@ tgdt:
         .quad   0x00cf93000000ffff      # __KERNEL_DS
 tgdt_end:
 
-        .data
-        .balign 4
-GLOBAL(trampoline_status)
-        .long   0
-
-trampoline_stack:
-        .org 0x1000
-trampoline_stack_end:
-
-        .globl  level3_ident_pgt
-        .globl  level3_kernel_pgt
-GLOBAL(trampoline_level4_pgt)
-        level3_ident_pgt:       .quad   0
-        .fill 510,8,0
-        level3_kernel_pgt:      .quad   0
-
-        .globl  startup_64_smp
-        .globl  startup_64_smp_high
-startup_64_smp:         .long 0
-startup_64_smp_high:    .long 0
+        .bss
+
+        .balign PAGE_SIZE
+GLOBAL(level3_ident_pgt)        .space  511*8
+GLOBAL(level3_kernel_pgt)       .space  8
+
+        .balign 8
+GLOBAL(startup_64_smp)          .space  8
+GLOBAL(trampoline_status)       .space  4
diff --git a/arch/x86/realmode/rm/wakeup/wakeup_asm.S b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
index 8064e1c3591b..f81c1cd99eaf 100644
--- a/arch/x86/realmode/rm/wakeup/wakeup_asm.S
+++ b/arch/x86/realmode/rm/wakeup/wakeup_asm.S
@@ -1,6 +1,7 @@
 /*
  * ACPI wakeup real mode startup stub
  */
+#include <linux/linkage.h>
 #include <asm/segment.h>
 #include <asm/msr-index.h>
 #include <asm/page_types.h>
@@ -9,31 +10,33 @@
 #include "../realmode.h"
 #include "wakeup.h"
 
-                .code16
+        .code16
 
 /* This should match the structure in wakeup.h */
-                .section ".data", "aw"
-                .globl  wakeup_header
-wakeup_header:
-video_mode:     .short  0       /* Video mode number */
-pmode_entry:    .long   0
-pmode_cs:       .short  __KERNEL_CS
-pmode_cr0:      .long   0       /* Saved %cr0 */
-pmode_cr3:      .long   0       /* Saved %cr3 */
-pmode_cr4:      .long   0       /* Saved %cr4 */
-pmode_efer:     .quad   0       /* Saved EFER */
-pmode_gdt:      .quad   0
-pmode_misc_en:  .quad   0       /* Saved MISC_ENABLE MSR */
-pmode_behavior: .long   0       /* Wakeup behavior flags */
-realmode_flags: .long   0
-real_magic:     .long   0
-signature:      .long   WAKEUP_HEADER_SIGNATURE
-                .size   wakeup_header, .-wakeup_header
+        .section ".data", "aw"
+
+        .balign 16
+GLOBAL(wakeup_header)
+        video_mode:     .short  0       /* Video mode number */
+        pmode_entry:    .long   0
+        pmode_cs:       .short  __KERNEL_CS
+        pmode_cr0:      .long   0       /* Saved %cr0 */
+        pmode_cr3:      .long   0       /* Saved %cr3 */
+        pmode_cr4:      .long   0       /* Saved %cr4 */
+        pmode_efer:     .quad   0       /* Saved EFER */
+        pmode_gdt:      .quad   0
+        pmode_misc_en:  .quad   0       /* Saved MISC_ENABLE MSR */
+        pmode_behavior: .long   0       /* Wakeup behavior flags */
+        realmode_flags: .long   0
+        real_magic:     .long   0
+        signature:      .long   WAKEUP_HEADER_SIGNATURE
+END(wakeup_header)
 
         .text
         .code16
-        .globl  wakeup_start
-wakeup_start:
+
+        .balign 16
+ENTRY(wakeup_start)
         cli
         cld
 
@@ -62,12 +65,14 @@ wakeup_start:
 3:
         /* Set up segments */
         movw    %cs, %ax
+        movw    %ax, %ss
+        movl    $rm_stack_end, %esp
         movw    %ax, %ds
         movw    %ax, %es
-        movw    %ax, %ss
-        lidtl   wakeup_idt
+        movw    %ax, %fs
+        movw    %ax, %gs
 
-        movl    $wakeup_stack_end, %esp
+        lidtl   wakeup_idt
 
         /* Clear the EFLAGS */
         pushl   $0
@@ -145,9 +150,8 @@ bogus_real_magic:
          * be the case for other laptops or integrated video devices.
          */
 
-        .globl  wakeup_gdt
         .balign 16
-wakeup_gdt:
+GLOBAL(wakeup_gdt)
         .word   3*8-1           /* Self-descriptor */
         .long   pa_wakeup_gdt
         .word   0
@@ -159,29 +163,18 @@ wakeup_gdt:
         .word   0xffff          /* 16-bit data segment @ real_mode_base */
         .long   0x93000000 + pa_real_mode_base
         .word   0x008f          /* big real mode */
-        .size   wakeup_gdt, .-wakeup_gdt
+END(wakeup_gdt)
 
-        .data
+        .section ".rodata","a"
         .balign 8
 
         /* This is the standard real-mode IDT */
-wakeup_idt:
+        .balign 16
+GLOBAL(wakeup_idt)
         .word   0xffff          /* limit */
         .long   0               /* address */
         .word   0
-
-        .globl  HEAP, heap_end
-HEAP:
-        .long   wakeup_heap
-heap_end:
-        .long   wakeup_stack
-
-        .bss
-wakeup_heap:
-        .space  2048
-wakeup_stack:
-        .space  2048
-wakeup_stack_end:
+END(wakeup_idt)
 
         .section ".signature","a"
 end_signature:
diff --git a/arch/x86/realmode/rmpiggy.S b/arch/x86/realmode/rmpiggy.S
index 6047d7f604cf..fd72a99d12ae 100644
--- a/arch/x86/realmode/rmpiggy.S
+++ b/arch/x86/realmode/rmpiggy.S
@@ -9,10 +9,10 @@
 
         .balign PAGE_SIZE
 
-ENTRY(real_mode_blob)
+GLOBAL(real_mode_blob)
         .incbin "arch/x86/realmode/rm/realmode.bin"
 END(real_mode_blob)
 
-ENTRY(real_mode_relocs)
+GLOBAL(real_mode_relocs)
         .incbin "arch/x86/realmode/rm/realmode.relocs"
 END(real_mode_relocs)