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04b5de3a8f
Commit 87e81786b1 ("x86/idt: Move early IDT setup out of 32-bit asm")
switched early_ignore_irq to use ENTRY. ENTRY aligns the code, so there
is no need for one more ALIGN right before the function.
And add one \n after the function to separate it from the data.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Link: http://lkml.kernel.org/r/20170831121653.28917-1-jslaby@suse.cz
615 lines
14 KiB
ArmAsm
615 lines
14 KiB
ArmAsm
/*
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* Enhanced CPU detection and feature setting code by Mike Jagdis
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* and Martin Mares, November 1997.
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*/
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.text
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#include <linux/threads.h>
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#include <linux/init.h>
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#include <linux/linkage.h>
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#include <asm/segment.h>
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#include <asm/page_types.h>
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#include <asm/pgtable_types.h>
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#include <asm/cache.h>
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#include <asm/thread_info.h>
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#include <asm/asm-offsets.h>
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#include <asm/setup.h>
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#include <asm/processor-flags.h>
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#include <asm/msr-index.h>
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#include <asm/cpufeatures.h>
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#include <asm/percpu.h>
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#include <asm/nops.h>
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#include <asm/bootparam.h>
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#include <asm/export.h>
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#include <asm/pgtable_32.h>
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/* Physical address */
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#define pa(X) ((X) - __PAGE_OFFSET)
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/*
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* References to members of the new_cpu_data structure.
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*/
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#define X86 new_cpu_data+CPUINFO_x86
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#define X86_VENDOR new_cpu_data+CPUINFO_x86_vendor
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#define X86_MODEL new_cpu_data+CPUINFO_x86_model
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#define X86_MASK new_cpu_data+CPUINFO_x86_mask
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#define X86_HARD_MATH new_cpu_data+CPUINFO_hard_math
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#define X86_CPUID new_cpu_data+CPUINFO_cpuid_level
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#define X86_CAPABILITY new_cpu_data+CPUINFO_x86_capability
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#define X86_VENDOR_ID new_cpu_data+CPUINFO_x86_vendor_id
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#define SIZEOF_PTREGS 17*4
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/*
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* Worst-case size of the kernel mapping we need to make:
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* a relocatable kernel can live anywhere in lowmem, so we need to be able
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* to map all of lowmem.
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*/
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KERNEL_PAGES = LOWMEM_PAGES
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INIT_MAP_SIZE = PAGE_TABLE_SIZE(KERNEL_PAGES) * PAGE_SIZE
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RESERVE_BRK(pagetables, INIT_MAP_SIZE)
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/*
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* 32-bit kernel entrypoint; only used by the boot CPU. On entry,
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* %esi points to the real-mode code as a 32-bit pointer.
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* CS and DS must be 4 GB flat segments, but we don't depend on
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* any particular GDT layout, because we load our own as soon as we
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* can.
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*/
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__HEAD
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ENTRY(startup_32)
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movl pa(initial_stack),%ecx
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/* test KEEP_SEGMENTS flag to see if the bootloader is asking
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us to not reload segments */
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testb $KEEP_SEGMENTS, BP_loadflags(%esi)
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jnz 2f
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/*
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* Set segments to known values.
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*/
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lgdt pa(boot_gdt_descr)
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movl $(__BOOT_DS),%eax
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movl %eax,%ds
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movl %eax,%es
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movl %eax,%fs
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movl %eax,%gs
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movl %eax,%ss
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2:
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leal -__PAGE_OFFSET(%ecx),%esp
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/*
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* Clear BSS first so that there are no surprises...
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*/
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cld
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xorl %eax,%eax
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movl $pa(__bss_start),%edi
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movl $pa(__bss_stop),%ecx
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subl %edi,%ecx
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shrl $2,%ecx
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rep ; stosl
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/*
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* Copy bootup parameters out of the way.
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* Note: %esi still has the pointer to the real-mode data.
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* With the kexec as boot loader, parameter segment might be loaded beyond
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* kernel image and might not even be addressable by early boot page tables.
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* (kexec on panic case). Hence copy out the parameters before initializing
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* page tables.
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*/
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movl $pa(boot_params),%edi
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movl $(PARAM_SIZE/4),%ecx
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cld
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rep
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movsl
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movl pa(boot_params) + NEW_CL_POINTER,%esi
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andl %esi,%esi
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jz 1f # No command line
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movl $pa(boot_command_line),%edi
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movl $(COMMAND_LINE_SIZE/4),%ecx
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rep
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movsl
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1:
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#ifdef CONFIG_OLPC
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/* save OFW's pgdir table for later use when calling into OFW */
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movl %cr3, %eax
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movl %eax, pa(olpc_ofw_pgd)
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#endif
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#ifdef CONFIG_MICROCODE
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/* Early load ucode on BSP. */
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call load_ucode_bsp
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#endif
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/* Create early pagetables. */
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call mk_early_pgtbl_32
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/* Do early initialization of the fixmap area */
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movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax
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#ifdef CONFIG_X86_PAE
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#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */
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movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8)
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#else
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movl %eax,pa(initial_page_table+0xffc)
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#endif
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#ifdef CONFIG_PARAVIRT
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/* This is can only trip for a broken bootloader... */
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cmpw $0x207, pa(boot_params + BP_version)
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jb .Ldefault_entry
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/* Paravirt-compatible boot parameters. Look to see what architecture
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we're booting under. */
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movl pa(boot_params + BP_hardware_subarch), %eax
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cmpl $num_subarch_entries, %eax
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jae .Lbad_subarch
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movl pa(subarch_entries)(,%eax,4), %eax
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subl $__PAGE_OFFSET, %eax
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jmp *%eax
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.Lbad_subarch:
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WEAK(xen_entry)
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/* Unknown implementation; there's really
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nothing we can do at this point. */
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ud2a
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__INITDATA
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subarch_entries:
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.long .Ldefault_entry /* normal x86/PC */
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.long xen_entry /* Xen hypervisor */
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.long .Ldefault_entry /* Moorestown MID */
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num_subarch_entries = (. - subarch_entries) / 4
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.previous
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#else
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jmp .Ldefault_entry
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#endif /* CONFIG_PARAVIRT */
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#ifdef CONFIG_HOTPLUG_CPU
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/*
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* Boot CPU0 entry point. It's called from play_dead(). Everything has been set
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* up already except stack. We just set up stack here. Then call
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* start_secondary().
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*/
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ENTRY(start_cpu0)
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movl initial_stack, %ecx
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movl %ecx, %esp
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call *(initial_code)
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1: jmp 1b
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ENDPROC(start_cpu0)
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#endif
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/*
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* Non-boot CPU entry point; entered from trampoline.S
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* We can't lgdt here, because lgdt itself uses a data segment, but
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* we know the trampoline has already loaded the boot_gdt for us.
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*
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* If cpu hotplug is not supported then this code can go in init section
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* which will be freed later
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*/
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ENTRY(startup_32_smp)
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cld
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movl $(__BOOT_DS),%eax
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movl %eax,%ds
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movl %eax,%es
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movl %eax,%fs
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movl %eax,%gs
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movl pa(initial_stack),%ecx
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movl %eax,%ss
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leal -__PAGE_OFFSET(%ecx),%esp
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#ifdef CONFIG_MICROCODE
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/* Early load ucode on AP. */
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call load_ucode_ap
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#endif
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.Ldefault_entry:
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#define CR0_STATE (X86_CR0_PE | X86_CR0_MP | X86_CR0_ET | \
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X86_CR0_NE | X86_CR0_WP | X86_CR0_AM | \
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X86_CR0_PG)
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movl $(CR0_STATE & ~X86_CR0_PG),%eax
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movl %eax,%cr0
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/*
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* We want to start out with EFLAGS unambiguously cleared. Some BIOSes leave
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* bits like NT set. This would confuse the debugger if this code is traced. So
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* initialize them properly now before switching to protected mode. That means
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* DF in particular (even though we have cleared it earlier after copying the
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* command line) because GCC expects it.
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*/
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pushl $0
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popfl
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/*
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* New page tables may be in 4Mbyte page mode and may be using the global pages.
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*
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* NOTE! If we are on a 486 we may have no cr4 at all! Specifically, cr4 exists
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* if and only if CPUID exists and has flags other than the FPU flag set.
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*/
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movl $-1,pa(X86_CPUID) # preset CPUID level
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movl $X86_EFLAGS_ID,%ecx
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pushl %ecx
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popfl # set EFLAGS=ID
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pushfl
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popl %eax # get EFLAGS
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testl $X86_EFLAGS_ID,%eax # did EFLAGS.ID remained set?
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jz .Lenable_paging # hw disallowed setting of ID bit
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# which means no CPUID and no CR4
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xorl %eax,%eax
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cpuid
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movl %eax,pa(X86_CPUID) # save largest std CPUID function
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movl $1,%eax
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cpuid
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andl $~1,%edx # Ignore CPUID.FPU
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jz .Lenable_paging # No flags or only CPUID.FPU = no CR4
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movl pa(mmu_cr4_features),%eax
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movl %eax,%cr4
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testb $X86_CR4_PAE, %al # check if PAE is enabled
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jz .Lenable_paging
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/* Check if extended functions are implemented */
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movl $0x80000000, %eax
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cpuid
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/* Value must be in the range 0x80000001 to 0x8000ffff */
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subl $0x80000001, %eax
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cmpl $(0x8000ffff-0x80000001), %eax
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ja .Lenable_paging
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/* Clear bogus XD_DISABLE bits */
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call verify_cpu
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mov $0x80000001, %eax
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cpuid
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/* Execute Disable bit supported? */
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btl $(X86_FEATURE_NX & 31), %edx
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jnc .Lenable_paging
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/* Setup EFER (Extended Feature Enable Register) */
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movl $MSR_EFER, %ecx
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rdmsr
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btsl $_EFER_NX, %eax
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/* Make changes effective */
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wrmsr
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.Lenable_paging:
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/*
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* Enable paging
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*/
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movl $pa(initial_page_table), %eax
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movl %eax,%cr3 /* set the page table pointer.. */
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movl $CR0_STATE,%eax
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movl %eax,%cr0 /* ..and set paging (PG) bit */
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ljmp $__BOOT_CS,$1f /* Clear prefetch and normalize %eip */
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1:
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/* Shift the stack pointer to a virtual address */
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addl $__PAGE_OFFSET, %esp
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/*
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* start system 32-bit setup. We need to re-do some of the things done
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* in 16-bit mode for the "real" operations.
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*/
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movl setup_once_ref,%eax
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andl %eax,%eax
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jz 1f # Did we do this already?
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call *%eax
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1:
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/*
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* Check if it is 486
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*/
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movb $4,X86 # at least 486
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cmpl $-1,X86_CPUID
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je .Lis486
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/* get vendor info */
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xorl %eax,%eax # call CPUID with 0 -> return vendor ID
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cpuid
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movl %eax,X86_CPUID # save CPUID level
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movl %ebx,X86_VENDOR_ID # lo 4 chars
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movl %edx,X86_VENDOR_ID+4 # next 4 chars
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movl %ecx,X86_VENDOR_ID+8 # last 4 chars
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orl %eax,%eax # do we have processor info as well?
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je .Lis486
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movl $1,%eax # Use the CPUID instruction to get CPU type
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cpuid
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movb %al,%cl # save reg for future use
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andb $0x0f,%ah # mask processor family
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movb %ah,X86
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andb $0xf0,%al # mask model
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shrb $4,%al
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movb %al,X86_MODEL
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andb $0x0f,%cl # mask mask revision
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movb %cl,X86_MASK
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movl %edx,X86_CAPABILITY
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.Lis486:
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movl $0x50022,%ecx # set AM, WP, NE and MP
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movl %cr0,%eax
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andl $0x80000011,%eax # Save PG,PE,ET
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orl %ecx,%eax
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movl %eax,%cr0
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lgdt early_gdt_descr
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ljmp $(__KERNEL_CS),$1f
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1: movl $(__KERNEL_DS),%eax # reload all the segment registers
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movl %eax,%ss # after changing gdt.
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movl $(__USER_DS),%eax # DS/ES contains default USER segment
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movl %eax,%ds
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movl %eax,%es
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movl $(__KERNEL_PERCPU), %eax
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movl %eax,%fs # set this cpu's percpu
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movl $(__KERNEL_STACK_CANARY),%eax
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movl %eax,%gs
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xorl %eax,%eax # Clear LDT
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lldt %ax
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call *(initial_code)
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1: jmp 1b
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ENDPROC(startup_32_smp)
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#include "verify_cpu.S"
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/*
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* setup_once
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*
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* The setup work we only want to run on the BSP.
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*
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* Warning: %esi is live across this function.
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*/
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__INIT
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setup_once:
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#ifdef CONFIG_CC_STACKPROTECTOR
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/*
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* Configure the stack canary. The linker can't handle this by
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* relocation. Manually set base address in stack canary
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* segment descriptor.
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*/
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movl $gdt_page,%eax
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movl $stack_canary,%ecx
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movw %cx, 8 * GDT_ENTRY_STACK_CANARY + 2(%eax)
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shrl $16, %ecx
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movb %cl, 8 * GDT_ENTRY_STACK_CANARY + 4(%eax)
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movb %ch, 8 * GDT_ENTRY_STACK_CANARY + 7(%eax)
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#endif
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andl $0,setup_once_ref /* Once is enough, thanks */
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ret
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ENTRY(early_idt_handler_array)
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# 36(%esp) %eflags
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# 32(%esp) %cs
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# 28(%esp) %eip
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# 24(%rsp) error code
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i = 0
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.rept NUM_EXCEPTION_VECTORS
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.ifeq (EXCEPTION_ERRCODE_MASK >> i) & 1
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pushl $0 # Dummy error code, to make stack frame uniform
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.endif
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pushl $i # 20(%esp) Vector number
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jmp early_idt_handler_common
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i = i + 1
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.fill early_idt_handler_array + i*EARLY_IDT_HANDLER_SIZE - ., 1, 0xcc
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.endr
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ENDPROC(early_idt_handler_array)
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early_idt_handler_common:
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/*
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* The stack is the hardware frame, an error code or zero, and the
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* vector number.
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*/
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cld
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incl %ss:early_recursion_flag
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/* The vector number is in pt_regs->gs */
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cld
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pushl %fs /* pt_regs->fs (__fsh varies by model) */
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pushl %es /* pt_regs->es (__esh varies by model) */
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pushl %ds /* pt_regs->ds (__dsh varies by model) */
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pushl %eax /* pt_regs->ax */
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pushl %ebp /* pt_regs->bp */
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pushl %edi /* pt_regs->di */
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pushl %esi /* pt_regs->si */
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pushl %edx /* pt_regs->dx */
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pushl %ecx /* pt_regs->cx */
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pushl %ebx /* pt_regs->bx */
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/* Fix up DS and ES */
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movl $(__KERNEL_DS), %ecx
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movl %ecx, %ds
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movl %ecx, %es
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/* Load the vector number into EDX */
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movl PT_GS(%esp), %edx
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/* Load GS into pt_regs->gs (and maybe clobber __gsh) */
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movw %gs, PT_GS(%esp)
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movl %esp, %eax /* args are pt_regs (EAX), trapnr (EDX) */
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call early_fixup_exception
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popl %ebx /* pt_regs->bx */
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popl %ecx /* pt_regs->cx */
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popl %edx /* pt_regs->dx */
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popl %esi /* pt_regs->si */
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popl %edi /* pt_regs->di */
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popl %ebp /* pt_regs->bp */
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popl %eax /* pt_regs->ax */
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popl %ds /* pt_regs->ds (always ignores __dsh) */
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popl %es /* pt_regs->es (always ignores __esh) */
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popl %fs /* pt_regs->fs (always ignores __fsh) */
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popl %gs /* pt_regs->gs (always ignores __gsh) */
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decl %ss:early_recursion_flag
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addl $4, %esp /* pop pt_regs->orig_ax */
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iret
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ENDPROC(early_idt_handler_common)
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/* This is the default interrupt "handler" :-) */
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ENTRY(early_ignore_irq)
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cld
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#ifdef CONFIG_PRINTK
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pushl %eax
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pushl %ecx
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pushl %edx
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pushl %es
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pushl %ds
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movl $(__KERNEL_DS),%eax
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movl %eax,%ds
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movl %eax,%es
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cmpl $2,early_recursion_flag
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je hlt_loop
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incl early_recursion_flag
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pushl 16(%esp)
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pushl 24(%esp)
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pushl 32(%esp)
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pushl 40(%esp)
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pushl $int_msg
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call printk
|
|
|
|
call dump_stack
|
|
|
|
addl $(5*4),%esp
|
|
popl %ds
|
|
popl %es
|
|
popl %edx
|
|
popl %ecx
|
|
popl %eax
|
|
#endif
|
|
iret
|
|
|
|
hlt_loop:
|
|
hlt
|
|
jmp hlt_loop
|
|
ENDPROC(early_ignore_irq)
|
|
|
|
__INITDATA
|
|
.align 4
|
|
GLOBAL(early_recursion_flag)
|
|
.long 0
|
|
|
|
__REFDATA
|
|
.align 4
|
|
ENTRY(initial_code)
|
|
.long i386_start_kernel
|
|
ENTRY(setup_once_ref)
|
|
.long setup_once
|
|
|
|
/*
|
|
* BSS section
|
|
*/
|
|
__PAGE_ALIGNED_BSS
|
|
.align PAGE_SIZE
|
|
#ifdef CONFIG_X86_PAE
|
|
.globl initial_pg_pmd
|
|
initial_pg_pmd:
|
|
.fill 1024*KPMDS,4,0
|
|
#else
|
|
.globl initial_page_table
|
|
initial_page_table:
|
|
.fill 1024,4,0
|
|
#endif
|
|
initial_pg_fixmap:
|
|
.fill 1024,4,0
|
|
.globl empty_zero_page
|
|
empty_zero_page:
|
|
.fill 4096,1,0
|
|
.globl swapper_pg_dir
|
|
swapper_pg_dir:
|
|
.fill 1024,4,0
|
|
EXPORT_SYMBOL(empty_zero_page)
|
|
|
|
/*
|
|
* This starts the data section.
|
|
*/
|
|
#ifdef CONFIG_X86_PAE
|
|
__PAGE_ALIGNED_DATA
|
|
/* Page-aligned for the benefit of paravirt? */
|
|
.align PAGE_SIZE
|
|
ENTRY(initial_page_table)
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0 /* low identity map */
|
|
# if KPMDS == 3
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x2000),0
|
|
# elif KPMDS == 2
|
|
.long 0,0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR+0x1000),0
|
|
# elif KPMDS == 1
|
|
.long 0,0
|
|
.long 0,0
|
|
.long pa(initial_pg_pmd+PGD_IDENT_ATTR),0
|
|
# else
|
|
# error "Kernel PMDs should be 1, 2 or 3"
|
|
# endif
|
|
.align PAGE_SIZE /* needs to be page-sized too */
|
|
#endif
|
|
|
|
.data
|
|
.balign 4
|
|
ENTRY(initial_stack)
|
|
/*
|
|
* The SIZEOF_PTREGS gap is a convention which helps the in-kernel
|
|
* unwinder reliably detect the end of the stack.
|
|
*/
|
|
.long init_thread_union + THREAD_SIZE - SIZEOF_PTREGS - \
|
|
TOP_OF_KERNEL_STACK_PADDING;
|
|
|
|
__INITRODATA
|
|
int_msg:
|
|
.asciz "Unknown interrupt or fault at: %p %p %p\n"
|
|
|
|
#include "../../x86/xen/xen-head.S"
|
|
|
|
/*
|
|
* The IDT and GDT 'descriptors' are a strange 48-bit object
|
|
* only used by the lidt and lgdt instructions. They are not
|
|
* like usual segment descriptors - they consist of a 16-bit
|
|
* segment size, and 32-bit linear address value:
|
|
*/
|
|
|
|
.data
|
|
.globl boot_gdt_descr
|
|
|
|
ALIGN
|
|
# early boot GDT descriptor (must use 1:1 address mapping)
|
|
.word 0 # 32 bit align gdt_desc.address
|
|
boot_gdt_descr:
|
|
.word __BOOT_DS+7
|
|
.long boot_gdt - __PAGE_OFFSET
|
|
|
|
# boot GDT descriptor (later on used by CPU#0):
|
|
.word 0 # 32 bit align gdt_desc.address
|
|
ENTRY(early_gdt_descr)
|
|
.word GDT_ENTRIES*8-1
|
|
.long gdt_page /* Overwritten for secondary CPUs */
|
|
|
|
/*
|
|
* The boot_gdt must mirror the equivalent in setup.S and is
|
|
* used only for booting.
|
|
*/
|
|
.align L1_CACHE_BYTES
|
|
ENTRY(boot_gdt)
|
|
.fill GDT_ENTRY_BOOT_CS,8,0
|
|
.quad 0x00cf9a000000ffff /* kernel 4GB code at 0x00000000 */
|
|
.quad 0x00cf92000000ffff /* kernel 4GB data at 0x00000000 */
|