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    Subject[patch V3 33/44] x86/idt: Move early IDT setup out of 32bit asm
    The early IDT setup can be done in C code like it's done on 64 bit. Reuse
    the 64 bit version.

    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
    ---
    arch/x86/include/asm/segment.h | 1 +
    arch/x86/kernel/head32.c | 4 ++++
    arch/x86/kernel/head_32.S | 36 ++----------------------------------
    arch/x86/kernel/idt.c | 4 ++++
    4 files changed, 11 insertions(+), 34 deletions(-)

    --- a/arch/x86/include/asm/segment.h
    +++ b/arch/x86/include/asm/segment.h
    @@ -238,6 +238,7 @@
    #ifndef __ASSEMBLY__

    extern const char early_idt_handler_array[NUM_EXCEPTION_VECTORS][EARLY_IDT_HANDLER_SIZE];
    +extern void early_ignore_irq(void);

    /*
    * Load a segment. Fall back on loading the zero segment if something goes
    --- a/arch/x86/kernel/head32.c
    +++ b/arch/x86/kernel/head32.c
    @@ -10,6 +10,7 @@
    #include <linux/mm.h>
    #include <linux/memblock.h>

    +#include <asm/desc.h>
    #include <asm/setup.h>
    #include <asm/sections.h>
    #include <asm/e820/api.h>
    @@ -30,6 +31,9 @@ static void __init i386_default_early_se
    asmlinkage __visible void __init i386_start_kernel(void)
    {
    cr4_init_shadow();
    +
    + idt_setup_early_handler();
    +
    sanitize_boot_params(&boot_params);

    x86_early_init_platform_quirks();
    --- a/arch/x86/kernel/head_32.S
    +++ b/arch/x86/kernel/head_32.S
    @@ -345,7 +345,6 @@ ENTRY(startup_32_smp)
    movl %eax,%cr0

    lgdt early_gdt_descr
    - lidt idt_descr
    ljmp $(__KERNEL_CS),$1f
    1: movl $(__KERNEL_DS),%eax # reload all the segment registers
    movl %eax,%ss # after changing gdt.
    @@ -378,37 +377,6 @@ ENDPROC(startup_32_smp)
    */
    __INIT
    setup_once:
    - /*
    - * Set up a idt with 256 interrupt gates that push zero if there
    - * is no error code and then jump to early_idt_handler_common.
    - * It doesn't actually load the idt - that needs to be done on
    - * each CPU. Interrupts are enabled elsewhere, when we can be
    - * relatively sure everything is ok.
    - */
    -
    - movl $idt_table,%edi
    - movl $early_idt_handler_array,%eax
    - movl $NUM_EXCEPTION_VECTORS,%ecx
    -1:
    - movl %eax,(%edi)
    - movl %eax,4(%edi)
    - /* interrupt gate, dpl=0, present */
    - movl $(0x8E000000 + __KERNEL_CS),2(%edi)
    - addl $EARLY_IDT_HANDLER_SIZE,%eax
    - addl $8,%edi
    - loop 1b
    -
    - movl $256 - NUM_EXCEPTION_VECTORS,%ecx
    - movl $ignore_int,%edx
    - movl $(__KERNEL_CS << 16),%eax
    - movw %dx,%ax /* selector = 0x0010 = cs */
    - movw $0x8E00,%dx /* interrupt gate - dpl=0, present */
    -2:
    - movl %eax,(%edi)
    - movl %edx,4(%edi)
    - addl $8,%edi
    - loop 2b
    -
    #ifdef CONFIG_CC_STACKPROTECTOR
    /*
    * Configure the stack canary. The linker can't handle this by
    @@ -498,7 +466,7 @@ ENDPROC(early_idt_handler_common)

    /* This is the default interrupt "handler" :-) */
    ALIGN
    -ignore_int:
    +ENTRY(early_ignore_irq)
    cld
    #ifdef CONFIG_PRINTK
    pushl %eax
    @@ -533,7 +501,7 @@ ENDPROC(early_idt_handler_common)
    hlt_loop:
    hlt
    jmp hlt_loop
    -ENDPROC(ignore_int)
    +ENDPROC(early_ignore_irq)
    __INITDATA
    .align 4
    GLOBAL(early_recursion_flag)
    --- a/arch/x86/kernel/idt.c
    +++ b/arch/x86/kernel/idt.c
    @@ -34,6 +34,10 @@ void __init idt_setup_early_handler(void

    for (i = 0; i < NUM_EXCEPTION_VECTORS; i++)
    set_intr_gate(i, early_idt_handler_array[i]);
    +#ifdef CONFIG_X86_32
    + for ( ; i < NR_VECTORS; i++)
    + set_intr_gate(i, early_ignore_irq);
    +#endif
    load_idt(&idt_descr);
    }


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