---

yaml
---
r: 305437
b: refs/heads/master
c: 4c5023a
h: refs/heads/master
i:
  305435: 1a56135
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 9900aa2f95844eb81428c1d3d202c01b7f3ac77a
+refs/heads/master: 4c5023a3fa2ec12b7ed313b276b157917575745b

trunk/arch/x86/kernel/head_32.S

@@ -21,6 +21,7 @@
 #include <asm/msr-index.h>
 #include <asm/cpufeature.h>
 #include <asm/percpu.h>
+#include <asm/nops.h>
 
 /* Physical address */
 #define pa(X) ((X) - __PAGE_OFFSET)
@@ -363,28 +364,23 @@ default_entry:
 	pushl $0
 	popfl
 
-#ifdef CONFIG_SMP
-	cmpb $0, ready
-	jnz checkCPUtype
-#endif /* CONFIG_SMP */
-
 /*
  * start system 32-bit setup. We need to re-do some of the things done
  * in 16-bit mode for the "real" operations.
  */
-	call setup_idt
-
-checkCPUtype:
-
-	movl $-1,X86_CPUID		#  -1 for no CPUID initially
-
+	movl setup_once_ref,%eax
+	andl %eax,%eax
+	jz 1f				# Did we do this already?
+	call *%eax
+1:
+	
 /* check if it is 486 or 386. */
 /*
  * XXX - this does a lot of unnecessary setup.  Alignment checks don't
  * apply at our cpl of 0 and the stack ought to be aligned already, and
  * we don't need to preserve eflags.
  */
-
+	movl $-1,X86_CPUID	# -1 for no CPUID initially
 	movb $3,X86		# at least 386
 	pushfl			# push EFLAGS
 	popl %eax		# get EFLAGS
@@ -450,21 +446,6 @@ is386:	movl $2,%ecx		# set MP
 	movl $(__KERNEL_PERCPU), %eax
 	movl %eax,%fs			# set this cpu's percpu
 
-#ifdef CONFIG_CC_STACKPROTECTOR
-	/*
-	 * The linker can't handle this by relocation.  Manually set
-	 * base address in stack canary segment descriptor.
-	 */
-	cmpb $0,ready
-	jne 1f
-	movl $gdt_page,%eax
-	movl $stack_canary,%ecx
-	movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
-	shrl $16, %ecx
-	movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
-	movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
-1:
-#endif
 	movl $(__KERNEL_STACK_CANARY),%eax
 	movl %eax,%gs
 
@@ -473,7 +454,6 @@ is386:	movl $2,%ecx		# set MP
 
 	cld			# gcc2 wants the direction flag cleared at all times
 	pushl $0		# fake return address for unwinder
-	movb $1, ready
 	jmp *(initial_code)
 
 /*
@@ -495,81 +475,122 @@ check_x87:
 	.byte 0xDB,0xE4		/* fsetpm for 287, ignored by 387 */
 	ret
 
+
+#include "verify_cpu.S"
+
 /*
- *  setup_idt
+ *  setup_once
  *
- *  sets up a idt with 256 entries pointing to
- *  ignore_int, interrupt gates. It doesn't actually load
- *  idt - that can be done only after paging has been enabled
- *  and the kernel moved to PAGE_OFFSET. Interrupts
- *  are enabled elsewhere, when we can be relatively
- *  sure everything is ok.
+ *  The setup work we only want to run on the BSP.
  *
  *  Warning: %esi is live across this function.
  */
-setup_idt:
-	lea ignore_int,%edx
-	movl $(__KERNEL_CS << 16),%eax
-	movw %dx,%ax		/* selector = 0x0010 = cs */
-	movw $0x8E00,%dx	/* interrupt gate - dpl=0, present */
+__INIT
+setup_once:
+	/*
+	 * Set up a idt with 256 entries pointing to ignore_int,
+	 * interrupt gates. It doesn't actually load idt - that needs
+	 * to be done on each CPU. Interrupts are enabled elsewhere,
+	 * when we can be relatively sure everything is ok.
+	 */
 
-	lea idt_table,%edi
-	mov $256,%ecx
-rp_sidt:
+	movl $idt_table,%edi
+	movl $early_idt_handlers,%eax
+	movl $NUM_EXCEPTION_VECTORS,%ecx
+1:
 	movl %eax,(%edi)
-	movl %edx,4(%edi)
+	movl %eax,4(%edi)
+	/* interrupt gate, dpl=0, present */
+	movl $(0x8E000000 + __KERNEL_CS),2(%edi)
+	addl $9,%eax
 	addl $8,%edi
-	dec %ecx
-	jne rp_sidt
+	loop 1b
 
-.macro	set_early_handler handler,trapno
-	lea \handler,%edx
+	movl $256 - NUM_EXCEPTION_VECTORS,%ecx
+	movl $ignore_int,%edx
 	movl $(__KERNEL_CS << 16),%eax
-	movw %dx,%ax
+	movw %dx,%ax		/* selector = 0x0010 = cs */
 	movw $0x8E00,%dx	/* interrupt gate - dpl=0, present */
-	lea idt_table,%edi
-	movl %eax,8*\trapno(%edi)
-	movl %edx,8*\trapno+4(%edi)
-.endm
+2:
+	movl %eax,(%edi)
+	movl %edx,4(%edi)
+	addl $8,%edi
+	loop 2b
 
-	set_early_handler handler=early_divide_err,trapno=0
-	set_early_handler handler=early_illegal_opcode,trapno=6
-	set_early_handler handler=early_protection_fault,trapno=13
-	set_early_handler handler=early_page_fault,trapno=14
+#ifdef CONFIG_CC_STACKPROTECTOR
+	/*
+	 * Configure the stack canary. The linker can't handle this by
+	 * relocation.  Manually set base address in stack canary
+	 * segment descriptor.
+	 */
+	movl $gdt_page,%eax
+	movl $stack_canary,%ecx
+	movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
+	shrl $16, %ecx
+	movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
+	movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
+#endif
 
+	andl $0,setup_once_ref	/* Once is enough, thanks */
 	ret
 
-early_divide_err:
-	xor %edx,%edx
-	pushl $0	/* fake errcode */
-	jmp early_fault
+ENTRY(early_idt_handlers)
+	# 36(%esp) %eflags
+	# 32(%esp) %cs
+	# 28(%esp) %eip
+	# 24(%rsp) error code
+	i = 0
+	.rept NUM_EXCEPTION_VECTORS
+	.if (EXCEPTION_ERRCODE_MASK >> i) & 1
+	ASM_NOP2
+	.else
+	pushl $0		# Dummy error code, to make stack frame uniform
+	.endif
+	pushl $i		# 20(%esp) Vector number
+	jmp early_idt_handler
+	i = i + 1
+	.endr
+ENDPROC(early_idt_handlers)
+
+	/* This is global to keep gas from relaxing the jumps */
+ENTRY(early_idt_handler)
+	cld
+	cmpl $2,%ss:early_recursion_flag
+	je hlt_loop
+	incl %ss:early_recursion_flag
 
-early_illegal_opcode:
-	movl $6,%edx
-	pushl $0	/* fake errcode */
-	jmp early_fault
+	push %eax		# 16(%esp)
+	push %ecx		# 12(%esp)
+	push %edx		#  8(%esp)
+	push %ds		#  4(%esp)
+	push %es		#  0(%esp)
+	movl $(__KERNEL_DS),%eax
+	movl %eax,%ds
+	movl %eax,%es
 
-early_protection_fault:
-	movl $13,%edx
-	jmp early_fault
+	cmpl $(__KERNEL_CS),32(%esp)
+	jne 10f
 
-early_page_fault:
-	movl $14,%edx
-	jmp early_fault
+	leal 28(%esp),%eax	# Pointer to %eip
+	call early_fixup_exception
+	andl %eax,%eax
+	jnz ex_entry		/* found an exception entry */
 
-early_fault:
-	cld
+10:
 #ifdef CONFIG_PRINTK
-	pusha
-	movl $(__KERNEL_DS),%eax
-	movl %eax,%ds
-	movl %eax,%es
-	cmpl $2,early_recursion_flag
-	je hlt_loop
-	incl early_recursion_flag
+	xorl %eax,%eax
+	movw %ax,2(%esp)	/* clean up the segment values on some cpus */
+	movw %ax,6(%esp)
+	movw %ax,34(%esp)
+	leal  40(%esp),%eax
+	pushl %eax		/* %esp before the exception */
+	pushl %ebx
+	pushl %ebp
+	pushl %esi
+	pushl %edi
 	movl %cr2,%eax
 	pushl %eax
-	pushl %edx		/* trapno */
+	pushl (20+6*4)(%esp)	/* trapno */
 	pushl $fault_msg
 	call printk
 #endif
@@ -578,6 +599,17 @@ hlt_loop:
 	hlt
 	jmp hlt_loop
 
+ex_entry:
+	pop %es
+	pop %ds
+	pop %edx
+	pop %ecx
+	pop %eax
+	addl $8,%esp		/* drop vector number and error code */
+	decl %ss:early_recursion_flag
+	iret
+ENDPROC(early_idt_handler)
+
 /* This is the default interrupt "handler" :-) */
 	ALIGN
 ignore_int:
@@ -611,13 +643,18 @@ ignore_int:
 	popl %eax
 #endif
 	iret
+ENDPROC(ignore_int)
+__INITDATA
+	.align 4
+early_recursion_flag:
+	.long 0
 
-#include "verify_cpu.S"
-
-	__REFDATA
-.align 4
+__REFDATA
+	.align 4
 ENTRY(initial_code)
 	.long i386_start_kernel
+ENTRY(setup_once_ref)
+	.long setup_once
 
 /*
  * BSS section
@@ -670,22 +707,19 @@ ENTRY(initial_page_table)
 ENTRY(stack_start)
 	.long init_thread_union+THREAD_SIZE
 
-early_recursion_flag:
-	.long 0
-
-ready:	.byte 0
-
+__INITRODATA
 int_msg:
 	.asciz "Unknown interrupt or fault at: %p %p %p\n"
 
 fault_msg:
 /* fault info: */
 	.ascii "BUG: Int %d: CR2 %p\n"
-/* pusha regs: */
-	.ascii "     EDI %p  ESI %p  EBP %p  ESP %p\n"
-	.ascii "     EBX %p  EDX %p  ECX %p  EAX %p\n"
+/* regs pushed in early_idt_handler: */
+	.ascii "     EDI %p  ESI %p  EBP %p  EBX %p\n"
+	.ascii "     ESP %p   ES %p   DS %p\n"
+	.ascii "     EDX %p  ECX %p  EAX %p\n"
 /* fault frame: */
-	.ascii "     err %p  EIP %p   CS %p  flg %p\n"
+	.ascii "     vec %p  err %p  EIP %p   CS %p  flg %p\n"
 	.ascii "Stack: %p %p %p %p %p %p %p %p\n"
 	.ascii "       %p %p %p %p %p %p %p %p\n"
 	.asciz "       %p %p %p %p %p %p %p %p\n"
@@ -699,6 +733,7 @@ fault_msg:
  * segment size, and 32-bit linear address value:
  */
 
+	.data
 .globl boot_gdt_descr
 .globl idt_descr