xnu-1699.26.8.tar.gz

[apple/xnu.git] / osfmk / x86_64 / start.s

diff --git a/osfmk/x86_64/start.s b/osfmk/x86_64/start.s
index ccba4f64b213490f19a6e49987de07e11d185e6b..8ca246de3c1c9ed18996a46ff790df3758556b7d 100644 (file)
--- a/osfmk/x86_64/start.s
+++ b/osfmk/x86_64/start.s
@@ -84,7 +84,7 @@ EXT(low_intstack):
        .globl  EXT(gIOHibernateRestoreStack)
 EXT(gIOHibernateRestoreStack):
 
-       .set    ., .+INTSTACK_SIZE
+       .space  INTSTACK_SIZE
 
        .globl  EXT(low_eintstack)
 EXT(low_eintstack:)
@@ -101,7 +101,7 @@ EXT(gIOHibernateRestoreStackEnd):
        .align  12
        .globl  EXT(df_task_stack)
 EXT(df_task_stack):
-       .set    ., .+INTSTACK_SIZE
+       .space  INTSTACK_SIZE
        .globl  EXT(df_task_stack_end)
 EXT(df_task_stack_end):
 
@@ -112,37 +112,10 @@ EXT(df_task_stack_end):
        .align  12
        .globl  EXT(mc_task_stack)
 EXT(mc_task_stack):
-       .set    ., .+INTSTACK_SIZE
+       .space  INTSTACK_SIZE
        .globl  EXT(mc_task_stack_end)
 EXT(mc_task_stack_end):
 
-
-#if    MACH_KDB
-/*
- * Kernel debugger stack for each processor.
- */
-       .align  12
-       .globl  EXT(db_stack_store)
-EXT(db_stack_store):
-       .set    ., .+(INTSTACK_SIZE*MAX_CPUS)
-
-/*
- * Stack for last-ditch debugger task for each processor.
- */
-       .align  12
-       .globl  EXT(db_task_stack_store)
-EXT(db_task_stack_store):
-       .set    ., .+(INTSTACK_SIZE*MAX_CPUS)
-
-/*
- * per-processor kernel debugger stacks
- */
-       .align  ALIGN
-       .globl  EXT(kgdb_stack_store)
-EXT(kgdb_stack_store):
-       .set    ., .+(INTSTACK_SIZE*MAX_CPUS)
-#endif /* MACH_KDB */
-
 /*
  * BSP CPU start here.
  *     eax points to kernbootstruct
@@ -176,7 +149,6 @@ EXT(kgdb_stack_store):
  * This proves that Little Endian is superior to Big Endian.
  */
        
-
        .text
        .align  ALIGN
        .globl  EXT(_start)
@@ -222,14 +194,6 @@ LEXT(_pstart)
        movl    $EXT(protected_mode_gdtr), %eax
        lgdtl   (%eax)
 
-       mov     $(KERNEL_DS), %ax
-       mov     %ax, %ds
-       mov     %ax, %es
-       mov     %ax, %ss
-       xor     %eax, %eax
-       mov     %ax, %fs
-       mov %ax, %gs
-
 /* the following code is shared by the master CPU and all slave CPUs */
 L_pstart_common:
        /*
@@ -237,6 +201,14 @@ L_pstart_common:
         */
        SWITCH_TO_64BIT_MODE
 
+       /* Flush data segment selectors */
+       xor     %eax, %eax
+       mov     %ax, %ss
+       mov     %ax, %ds
+       mov     %ax, %es
+       mov     %ax, %fs
+       mov     %ax, %gs
+
        /* %edi = boot_args_start */
        
        leaq _vstart(%rip), %rcx
@@ -441,8 +413,12 @@ ENTRY(acpi_sleep_cpu)
        movw    %gs, saved_gs(%rip)
        movw    %ss, saved_ss(%rip)     
 
-       /* save the 64bit kernel gs base */
+       /* save the 64bit user and kernel gs base */
+       /* note: user's curently swapped into kernel base MSR */
        mov     $MSR_IA32_KERNEL_GS_BASE, %rcx
+       rdmsr
+       movl    %eax, saved_ugs_base(%rip)
+       movl    %edx, saved_ugs_base+4(%rip)
        swapgs
        rdmsr
        movl    %eax, saved_kgs_base(%rip)
@@ -519,8 +495,9 @@ Lwake_64:
        /* protected mode, paging enabled */
        POSTCODE(ACPI_WAKE_PAGED_ENTRY)
 
-       /* switch to kernel data segment */
-       movw    $(KERNEL_DS), %ax
+       /* load null segment selectors */
+       xor     %eax, %eax
+       movw    %ax, %ss
        movw    %ax, %ds
 
        /* restore local and interrupt descriptor tables */
@@ -533,14 +510,16 @@ Lwake_64:
        movw    saved_gs(%rip), %gs
        movw    saved_ss(%rip), %ss
 
-       /* save the 64bit kernel gs base */
+       /* restore the 64bit kernel and user gs base */
        mov     $MSR_IA32_KERNEL_GS_BASE, %rcx
        movl    saved_kgs_base(%rip),   %eax 
        movl    saved_kgs_base+4(%rip), %edx 
        wrmsr
        swapgs
+       movl    saved_ugs_base(%rip),   %eax 
+       movl    saved_ugs_base+4(%rip), %edx 
+       wrmsr
 
-       //K64todo verify this TSS stuff
        /*
         * Restore task register. Before doing this, clear the busy flag
         * in the TSS descriptor set by the CPU.
@@ -661,4 +640,5 @@ saved_idt:  .word 0
 saved_ldt:     .word 0
 saved_tr:      .word 0
 saved_kgs_base:        .quad 0
+saved_ugs_base:        .quad 0