From d50d8fe192428090790e7178e9507e981e0b005b Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 4 Jan 2011 17:20:54 +1030 Subject: x86, mm: Initialize initial_page_table before paravirt jumps v2.6.36-rc8-54-gb40827f (x86-32, mm: Add an initial page table for core bootstrapping) made x86 boot using initial_page_table and broke lguest. For 2.6.37 we simply cut & paste the initialization code into lguest (da32dac10126 "lguest: populate initial_page_table"), now we fix it properly by doing that initialization before the paravirt jump. Signed-off-by: Rusty Russell Acked-by: Jeremy Fitzhardinge Cc: lguest Cc: Linus Torvalds Cc: Andrew Morton Cc: Peter Zijlstra LKML-Reference: <201101041720.54535.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar --- arch/x86/lguest/i386_head.S | 105 -------------------------------------------- 1 file changed, 105 deletions(-) (limited to 'arch/x86/lguest') diff --git a/arch/x86/lguest/i386_head.S b/arch/x86/lguest/i386_head.S index e7d5382ef263..4f420c2f2d55 100644 --- a/arch/x86/lguest/i386_head.S +++ b/arch/x86/lguest/i386_head.S @@ -4,7 +4,6 @@ #include #include #include -#include /*G:020 * Our story starts with the kernel booting into startup_32 in @@ -38,113 +37,9 @@ ENTRY(lguest_entry) /* Set up the initial stack so we can run C code. */ movl $(init_thread_union+THREAD_SIZE),%esp - call init_pagetables - /* Jumps are relative: we're running __PAGE_OFFSET too low. */ jmp lguest_init+__PAGE_OFFSET -/* - * Initialize page tables. This creates a PDE and a set of page - * tables, which are located immediately beyond __brk_base. The variable - * _brk_end is set up to point to the first "safe" location. - * Mappings are created both at virtual address 0 (identity mapping) - * and PAGE_OFFSET for up to _end. - * - * FIXME: This code is taken verbatim from arch/x86/kernel/head_32.S: they - * don't have a stack at this point, so we can't just use call and ret. - */ -init_pagetables: -#if PTRS_PER_PMD > 1 -#define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD) -#else -#define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD) -#endif -#define pa(X) ((X) - __PAGE_OFFSET) - -/* Enough space to fit pagetables for the low memory linear map */ -MAPPING_BEYOND_END = \ - PAGE_TABLE_SIZE(((1<<32) - __PAGE_OFFSET) >> PAGE_SHIFT) << PAGE_SHIFT -#ifdef CONFIG_X86_PAE - - /* - * In PAE mode initial_page_table is statically defined to contain - * enough entries to cover the VMSPLIT option (that is the top 1, 2 or 3 - * entries). The identity mapping is handled by pointing two PGD entries - * to the first kernel PMD. - * - * Note the upper half of each PMD or PTE are always zero at this stage. - */ - -#define KPMDS (((-__PAGE_OFFSET) >> 30) & 3) /* Number of kernel PMDs */ - - xorl %ebx,%ebx /* %ebx is kept at zero */ - - movl $pa(__brk_base), %edi - movl $pa(initial_pg_pmd), %edx - movl $PTE_IDENT_ATTR, %eax -10: - leal PDE_IDENT_ATTR(%edi),%ecx /* Create PMD entry */ - movl %ecx,(%edx) /* Store PMD entry */ - /* Upper half already zero */ - addl $8,%edx - movl $512,%ecx -11: - stosl - xchgl %eax,%ebx - stosl - xchgl %eax,%ebx - addl $0x1000,%eax - loop 11b - - /* - * End condition: we must map up to the end + MAPPING_BEYOND_END. - */ - movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp - cmpl %ebp,%eax - jb 10b -1: - addl $__PAGE_OFFSET, %edi - movl %edi, pa(_brk_end) - shrl $12, %eax - movl %eax, pa(max_pfn_mapped) - - /* Do early initialization of the fixmap area */ - movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax - movl %eax,pa(initial_pg_pmd+0x1000*KPMDS-8) -#else /* Not PAE */ - -page_pde_offset = (__PAGE_OFFSET >> 20); - - movl $pa(__brk_base), %edi - movl $pa(initial_page_table), %edx - movl $PTE_IDENT_ATTR, %eax -10: - leal PDE_IDENT_ATTR(%edi),%ecx /* Create PDE entry */ - movl %ecx,(%edx) /* Store identity PDE entry */ - movl %ecx,page_pde_offset(%edx) /* Store kernel PDE entry */ - addl $4,%edx - movl $1024, %ecx -11: - stosl - addl $0x1000,%eax - loop 11b - /* - * End condition: we must map up to the end + MAPPING_BEYOND_END. - */ - movl $pa(_end) + MAPPING_BEYOND_END + PTE_IDENT_ATTR, %ebp - cmpl %ebp,%eax - jb 10b - addl $__PAGE_OFFSET, %edi - movl %edi, pa(_brk_end) - shrl $12, %eax - movl %eax, pa(max_pfn_mapped) - - /* Do early initialization of the fixmap area */ - movl $pa(initial_pg_fixmap)+PDE_IDENT_ATTR,%eax - movl %eax,pa(initial_page_table+0xffc) -#endif - ret - /*G:055 * We create a macro which puts the assembler code between lgstart_ and lgend_ * markers. These templates are put in the .text section: they can't be -- cgit v1.2.3