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4c5023a3fa
If we get an exception during early boot, walk the exception table to see if we should intercept it. The main use case for this is to allow rdmsr_safe()/wrmsr_safe() during CPU initialization. Since the exception table is currently sorted at runtime, and fairly late in startup, this code walks the exception table linearly. We obviously don't need to worry about modules, however: none have been loaded at this point. This patch changes the early IDT setup to look a lot more like x86-64: we now install handlers for all 32 exception vectors. The output of the early exception handler has changed somewhat as it directly reflects the stack frame of the exception handler, and the stack frame has been somewhat restructured. Finally, centralize the code that can and should be run only once. [ v2: Use early_fixup_exception() instead of linear search ] Signed-off-by: H. Peter Anvin <hpa@zytor.com> Link: http://lkml.kernel.org/r/1334794610-5546-6-git-send-email-hpa@zytor.com
767 lines
18 KiB
ArmAsm
767 lines
18 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/cpufeature.h>
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#include <asm/percpu.h>
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#include <asm/nops.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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/*
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* This is how much memory in addition to the memory covered up to
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* and including _end we need mapped initially.
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* We need:
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* (KERNEL_IMAGE_SIZE/4096) / 1024 pages (worst case, non PAE)
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* (KERNEL_IMAGE_SIZE/4096) / 512 + 4 pages (worst case for PAE)
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*
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* Modulo rounding, each megabyte assigned here requires a kilobyte of
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* memory, which is currently unreclaimed.
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*
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* This should be a multiple of a page.
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*
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* KERNEL_IMAGE_SIZE should be greater than pa(_end)
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* and small than max_low_pfn, otherwise will waste some page table entries
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*/
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#if PTRS_PER_PMD > 1
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#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
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#else
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#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
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#endif
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/* Number of possible pages in the lowmem region */
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LOWMEM_PAGES = (((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT)
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/* Enough space to fit pagetables for the low memory linear map */
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MAPPING_BEYOND_END = PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT
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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(stack_start),%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 $(1<<6), 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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/*
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* Initialize page tables. This creates a PDE and a set of page
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* tables, which are located immediately beyond __brk_base. The variable
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* _brk_end is set up to point to the first "safe" location.
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* Mappings are created both at virtual address 0 (identity mapping)
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* and PAGE_OFFSET for up to _end.
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*/
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#ifdef CONFIG_X86_PAE
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/*
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* In PAE mode initial_page_table is statically defined to contain
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* enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3
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* entries). The identity mapping is handled by pointing two PGD entries
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* to the first kernel PMD.
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*
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* Note the upper half of each PMD or PTE are always zero at this stage.
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*/
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#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */
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xorl %ebx,%ebx /* %ebx is kept at zero */
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movl $pa(__brk_base), %edi
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movl $pa(initial_pg_pmd), %edx
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movl $PTE_IDENT_ATTR, %eax
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10:
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leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */
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movl %ecx,(%edx) /* Store PMD entry */
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/* Upper half already zero */
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addl $8,%edx
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movl $512,%ecx
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11:
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stosl
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xchgl %eax,%ebx
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stosl
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xchgl %eax,%ebx
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addl $0x1000,%eax
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loop 11b
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/*
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* End condition: we must map up to the end + MAPPING_BEYOND_END.
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*/
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movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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cmpl %ebp,%eax
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jb 10b
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1:
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addl $__PAGE_OFFSET, %edi
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movl %edi, pa(_brk_end)
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shrl $12, %eax
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movl %eax, pa(max_pfn_mapped)
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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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movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8)
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#else /* Not PAE */
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page_pde_offset = (__PAGE_OFFSET >> 20);
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movl $pa(__brk_base), %edi
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movl $pa(initial_page_table), %edx
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movl $PTE_IDENT_ATTR, %eax
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10:
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leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */
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movl %ecx,(%edx) /* Store identity PDE entry */
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movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */
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addl $4,%edx
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movl $1024, %ecx
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11:
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stosl
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addl $0x1000,%eax
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loop 11b
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/*
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* End condition: we must map up to the end + MAPPING_BEYOND_END.
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*/
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movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp
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cmpl %ebp,%eax
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jb 10b
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addl $__PAGE_OFFSET, %edi
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movl %edi, pa(_brk_end)
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shrl $12, %eax
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movl %eax, pa(max_pfn_mapped)
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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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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 default_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 bad_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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bad_subarch:
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WEAK(lguest_entry)
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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 default_entry /* normal x86/PC */
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.long lguest_entry /* lguest hypervisor */
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.long xen_entry /* Xen hypervisor */
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.long default_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 default_entry
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#endif /* CONFIG_PARAVIRT */
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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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__CPUINIT
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#ifdef CONFIG_SMP
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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(stack_start),%ecx
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movl %eax,%ss
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leal -__PAGE_OFFSET(%ecx),%esp
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#endif /* CONFIG_SMP */
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default_entry:
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/*
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* New page tables may be in 4Mbyte page mode and may
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* 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!
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* So we do not try to touch it unless we really have
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* some bits in it to set. This won't work if the BSP
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* implements cr4 but this AP does not -- very unlikely
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* but be warned! The same applies to the pse feature
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* if not equally supported. --macro
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*
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* NOTE! We have to correct for the fact that we're
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* not yet offset PAGE_OFFSET..
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*/
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#define cr4_bits pa(mmu_cr4_features)
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movl cr4_bits,%edx
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andl %edx,%edx
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jz 6f
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movl %cr4,%eax # Turn on paging options (PSE,PAE,..)
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orl %edx,%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 6f
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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 6f
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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 6f
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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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6:
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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,%eax
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orl $X86_CR0_PG,%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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* Initialize eflags. Some BIOS's leave bits like NT set. This would
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* confuse the debugger if this code is traced.
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* XXX - best to initialize before switching to protected mode.
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*/
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pushl $0
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popfl
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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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/* check if it is 486 or 386. */
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/*
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* XXX - this does a lot of unnecessary setup. Alignment checks don't
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* apply at our cpl of 0 and the stack ought to be aligned already, and
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* we don't need to preserve eflags.
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*/
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movl $-1,X86_CPUID # -1 for no CPUID initially
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movb $3,X86 # at least 386
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pushfl # push EFLAGS
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popl %eax # get EFLAGS
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movl %eax,%ecx # save original EFLAGS
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xorl $0x240000,%eax # flip AC and ID bits in EFLAGS
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pushl %eax # copy to EFLAGS
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popfl # set EFLAGS
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pushfl # get new EFLAGS
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popl %eax # put it in eax
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xorl %ecx,%eax # change in flags
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pushl %ecx # restore original EFLAGS
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popfl
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testl $0x40000,%eax # check if AC bit changed
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je is386
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movb $4,X86 # at least 486
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testl $0x200000,%eax # check if ID bit changed
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je is486
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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 is486
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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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is486: movl $0x50022,%ecx # set AM, WP, NE and MP
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jmp 2f
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is386: movl $2,%ecx # set MP
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2: 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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call check_x87
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lgdt early_gdt_descr
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lidt idt_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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cld # gcc2 wants the direction flag cleared at all times
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pushl $0 # fake return address for unwinder
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jmp *(initial_code)
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/*
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* We depend on ET to be correct. This checks for 287/387.
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*/
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check_x87:
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movb $0,X86_HARD_MATH
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clts
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fninit
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fstsw %ax
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cmpb $0,%al
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je 1f
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movl %cr0,%eax /* no coprocessor: have to set bits */
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xorl $4,%eax /* set EM */
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movl %eax,%cr0
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ret
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ALIGN
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1: movb $1,X86_HARD_MATH
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.byte 0xDB,0xE4 /* fsetpm for 287, ignored by 387 */
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ret
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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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/*
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* Set up a idt with 256 entries pointing to ignore_int,
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* 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.
|
|
*/
|
|
|
|
movl $idt_table,%edi
|
|
movl $early_idt_handlers,%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 $9,%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
|
|
* 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
|
|
|
|
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
|
|
|
|
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
|
|
|
|
cmpl $(__KERNEL_CS),32(%esp)
|
|
jne 10f
|
|
|
|
leal 28(%esp),%eax # Pointer to %eip
|
|
call early_fixup_exception
|
|
andl %eax,%eax
|
|
jnz ex_entry /* found an exception entry */
|
|
|
|
10:
|
|
#ifdef CONFIG_PRINTK
|
|
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 (20+6*4)(%esp) /* trapno */
|
|
pushl $fault_msg
|
|
call printk
|
|
#endif
|
|
call dump_stack
|
|
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:
|
|
cld
|
|
#ifdef CONFIG_PRINTK
|
|
pushl %eax
|
|
pushl %ecx
|
|
pushl %edx
|
|
pushl %es
|
|
pushl %ds
|
|
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)
|
|
pushl 40(%esp)
|
|
pushl $int_msg
|
|
call printk
|
|
|
|
call dump_stack
|
|
|
|
addl $(5*4),%esp
|
|
popl %ds
|
|
popl %es
|
|
popl %edx
|
|
popl %ecx
|
|
popl %eax
|
|
#endif
|
|
iret
|
|
ENDPROC(ignore_int)
|
|
__INITDATA
|
|
.align 4
|
|
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
|
|
initial_pg_pmd:
|
|
.fill 1024*KPMDS,4,0
|
|
#else
|
|
ENTRY(initial_page_table)
|
|
.fill 1024,4,0
|
|
#endif
|
|
initial_pg_fixmap:
|
|
.fill 1024,4,0
|
|
ENTRY(empty_zero_page)
|
|
.fill 4096,1,0
|
|
ENTRY(swapper_pg_dir)
|
|
.fill 1024,4,0
|
|
|
|
/*
|
|
* 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(stack_start)
|
|
.long init_thread_union+THREAD_SIZE
|
|
|
|
__INITRODATA
|
|
int_msg:
|
|
.asciz "Unknown interrupt or fault at: %p %p %p\n"
|
|
|
|
fault_msg:
|
|
/* fault info: */
|
|
.ascii "BUG: Int %d: CR2 %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 " 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"
|
|
|
|
#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
|
|
.globl idt_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
|
|
|
|
.word 0 # 32-bit align idt_desc.address
|
|
idt_descr:
|
|
.word IDT_ENTRIES*8-1 # idt contains 256 entries
|
|
.long idt_table
|
|
|
|
# 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 */
|