X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fi386%2Fkernel%2Fhead.S;h=edef5084ce17104b6c46f900d70d22b480ed8794;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=e0b7c632efbcb63fa6704baae50b300422da624e;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S index e0b7c632e..edef5084c 100644 --- a/arch/i386/kernel/head.S +++ b/arch/i386/kernel/head.S @@ -8,7 +8,6 @@ */ .text -#include #include #include #include @@ -56,6 +55,12 @@ */ ENTRY(startup_32) +#ifdef CONFIG_PARAVIRT + movl %cs, %eax + testl $0x3, %eax + jnz startup_paravirt +#endif + /* * Set segments to known values. */ @@ -303,6 +308,7 @@ is386: movl $2,%ecx # set MP movl %eax,%cr0 call check_x87 + call setup_pda lgdt cpu_gdt_descr lidt idt_descr ljmp $(__KERNEL_CS),$1f @@ -313,25 +319,22 @@ is386: movl $2,%ecx # set MP movl %eax,%ds movl %eax,%es - xorl %eax,%eax # Clear FS/GS and LDT + xorl %eax,%eax # Clear FS and LDT movl %eax,%fs - movl %eax,%gs lldt %ax + + movl $(__KERNEL_PDA),%eax + mov %eax,%gs + cld # gcc2 wants the direction flag cleared at all times + pushl $0 # fake return address for unwinder #ifdef CONFIG_SMP movb ready, %cl movb $1, ready - cmpb $0,%cl - je 1f # the first CPU calls start_kernel - # all other CPUs call initialize_secondary - call initialize_secondary - jmp L6 -1: + cmpb $0,%cl # the first CPU calls start_kernel + jne initialize_secondary # all other CPUs call initialize_secondary #endif /* CONFIG_SMP */ - call start_kernel -L6: - jmp L6 # main should never return here, but - # just in case, we know what happens. + jmp start_kernel /* * We depend on ET to be correct. This checks for 287/387. @@ -352,6 +355,23 @@ check_x87: .byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */ ret +/* + * Point the GDT at this CPU's PDA. On boot this will be + * cpu_gdt_table and boot_pda; for secondary CPUs, these will be + * that CPU's GDT and PDA. + */ +setup_pda: + /* get the PDA pointer */ + movl start_pda, %eax + + /* slot the PDA address into the GDT */ + mov cpu_gdt_descr+2, %ecx + mov %ax, (__KERNEL_PDA+0+2)(%ecx) /* base & 0x0000ffff */ + shr $16, %eax + mov %al, (__KERNEL_PDA+4+0)(%ecx) /* base & 0x00ff0000 */ + mov %ah, (__KERNEL_PDA+4+3)(%ecx) /* base & 0xff000000 */ + ret + /* * setup_idt * @@ -378,8 +398,65 @@ rp_sidt: addl $8,%edi dec %ecx jne rp_sidt + +.macro set_early_handler handler,trapno + lea \handler,%edx + movl $(__KERNEL_CS << 16),%eax + movw %dx,%ax + movw $0x8E00,%dx /* interrupt gate - dpl=0, present */ + lea idt_table,%edi + movl %eax,8*\trapno(%edi) + movl %edx,8*\trapno+4(%edi) +.endm + + 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 + ret +early_divide_err: + xor %edx,%edx + pushl $0 /* fake errcode */ + jmp early_fault + +early_illegal_opcode: + movl $6,%edx + pushl $0 /* fake errcode */ + jmp early_fault + +early_protection_fault: + movl $13,%edx + jmp early_fault + +early_page_fault: + movl $14,%edx + jmp early_fault + +early_fault: + cld +#ifdef CONFIG_PRINTK + movl $(__KERNEL_DS),%eax + movl %eax,%ds + movl %eax,%es + cmpl $2,early_recursion_flag + je hlt_loop + incl early_recursion_flag + movl %cr2,%eax + pushl %eax + pushl %edx /* trapno */ + pushl $fault_msg +#ifdef CONFIG_EARLY_PRINTK + call early_printk +#else + call printk +#endif +#endif +hlt_loop: + hlt + jmp hlt_loop + /* This is the default interrupt "handler" :-) */ ALIGN ignore_int: @@ -393,6 +470,9 @@ ignore_int: movl $(__KERNEL_DS),%eax movl %eax,%ds movl %eax,%es + cmpl $2,early_recursion_flag + je hlt_loop + incl early_recursion_flag pushl 16(%esp) pushl 24(%esp) pushl 32(%esp) @@ -412,6 +492,33 @@ ignore_int: #endif iret +#ifdef CONFIG_PARAVIRT +startup_paravirt: + cld + movl $(init_thread_union+THREAD_SIZE),%esp + + /* We take pains to preserve all the regs. */ + pushl %edx + pushl %ecx + pushl %eax + + /* paravirt.o is last in link, and that probe fn never returns */ + pushl $__start_paravirtprobe +1: + movl 0(%esp), %eax + pushl (%eax) + movl 8(%esp), %eax + call *(%esp) + popl %eax + + movl 4(%esp), %eax + movl 8(%esp), %ecx + movl 12(%esp), %edx + + addl $4, (%esp) + jmp 1b +#endif + /* * Real beginning of normal "text" segment */ @@ -431,6 +538,8 @@ ENTRY(empty_zero_page) * This starts the data section. */ .data +ENTRY(start_pda) + .long boot_pda ENTRY(stack_start) .long init_thread_union+THREAD_SIZE @@ -438,9 +547,16 @@ ENTRY(stack_start) ready: .byte 0 +early_recursion_flag: + .long 0 + int_msg: .asciz "Unknown interrupt or fault at EIP %p %p %p\n" +fault_msg: + .ascii "Int %d: CR2 %p err %p EIP %p CS %p flags %p\n" + .asciz "Stack: %p %p %p %p %p %p %p %p\n" + /* * The IDT and GDT 'descriptors' are a strange 48-bit object * only used by the lidt and lgdt instructions. They are not @@ -450,7 +566,6 @@ int_msg: .globl boot_gdt_descr .globl idt_descr -.globl cpu_gdt_descr ALIGN # early boot GDT descriptor (must use 1:1 address mapping) @@ -466,12 +581,10 @@ idt_descr: # boot GDT descriptor (later on used by CPU#0): .word 0 # 32 bit align gdt_desc.address -cpu_gdt_descr: +ENTRY(cpu_gdt_descr) .word GDT_ENTRIES*8-1 .long cpu_gdt_table - .fill NR_CPUS-1,8,0 # space for the other GDT descriptors - /* * The boot_gdt_table must mirror the equivalent in setup.S and is * used only for booting. @@ -485,7 +598,7 @@ ENTRY(boot_gdt_table) /* * The Global Descriptor Table contains 28 quadwords, per-CPU. */ - .align PAGE_SIZE_asm + .align L1_CACHE_BYTES ENTRY(cpu_gdt_table) .quad 0x0000000000000000 /* NULL descriptor */ .quad 0x0000000000000000 /* 0x0b reserved */ @@ -527,8 +640,8 @@ ENTRY(cpu_gdt_table) .quad 0x00009a000000ffff /* 0xc0 APM CS 16 code (16 bit) */ .quad 0x004092000000ffff /* 0xc8 APM DS data */ - .quad 0x0000920000000000 /* 0xd0 - ESPFIX 16-bit SS */ - .quad 0x0000000000000000 /* 0xd8 - unused */ + .quad 0x00c0920000000000 /* 0xd0 - ESPFIX SS */ + .quad 0x00cf92000000ffff /* 0xd8 - PDA */ .quad 0x0000000000000000 /* 0xe0 - unused */ .quad 0x0000000000000000 /* 0xe8 - unused */ .quad 0x0000000000000000 /* 0xf0 - unused */