| From 5988b32500933add4877201667ce7b1725254072 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@suse.de> |
| Date: Mon, 11 Apr 2011 16:04:59 -0700 |
| Subject: [PATCH] Revert "x86: Cleanup highmap after brk is concluded" |
| |
| This reverts upstream commit e5f15b45ddf3afa2bbbb10c7ea34fb32b6de0a0e |
| |
| It caused problems in the stable tree and should not have been there. |
| |
| Cc: Yinghai Lu <yinghai@kernel.org> |
| Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> |
| Cc: H. Peter Anvin <hpa@zytor.com> |
| Cc: Ingo Molnar <mingo@elte.hu> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| arch/x86/kernel/head64.c | 3 +++ |
| arch/x86/kernel/setup.c | 5 ----- |
| arch/x86/mm/init.c | 19 +++++++++++++++++++ |
| arch/x86/mm/init_64.c | 11 +++++------ |
| 4 files changed, 27 insertions(+), 11 deletions(-) |
| |
| --- a/arch/x86/kernel/head64.c |
| +++ b/arch/x86/kernel/head64.c |
| @@ -76,6 +76,9 @@ void __init x86_64_start_kernel(char * r |
| /* Make NULL pointers segfault */ |
| zap_identity_mappings(); |
| |
| + /* Cleanup the over mapped high alias */ |
| + cleanup_highmap(); |
| + |
| for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) { |
| #ifdef CONFIG_EARLY_PRINTK |
| set_intr_gate(i, &early_idt_handlers[i]); |
| --- a/arch/x86/kernel/setup.c |
| +++ b/arch/x86/kernel/setup.c |
| @@ -294,9 +294,6 @@ static void __init init_gbpages(void) |
| static inline void init_gbpages(void) |
| { |
| } |
| -static void __init cleanup_highmap(void) |
| -{ |
| -} |
| #endif |
| |
| static void __init reserve_brk(void) |
| @@ -924,8 +921,6 @@ void __init setup_arch(char **cmdline_p) |
| |
| reserve_brk(); |
| |
| - cleanup_highmap(); |
| - |
| init_gbpages(); |
| |
| /* max_pfn_mapped is updated here */ |
| --- a/arch/x86/mm/init.c |
| +++ b/arch/x86/mm/init.c |
| @@ -287,6 +287,25 @@ unsigned long __init_refok init_memory_m |
| load_cr3(swapper_pg_dir); |
| #endif |
| |
| +#ifdef CONFIG_X86_64 |
| + if (!after_bootmem && !start) { |
| + pud_t *pud; |
| + pmd_t *pmd; |
| + |
| + mmu_cr4_features = read_cr4(); |
| + |
| + /* |
| + * _brk_end cannot change anymore, but it and _end may be |
| + * located on different 2M pages. cleanup_highmap(), however, |
| + * can only consider _end when it runs, so destroy any |
| + * mappings beyond _brk_end here. |
| + */ |
| + pud = pud_offset(pgd_offset_k(_brk_end), _brk_end); |
| + pmd = pmd_offset(pud, _brk_end - 1); |
| + while (++pmd <= pmd_offset(pud, (unsigned long)_end - 1)) |
| + pmd_clear(pmd); |
| + } |
| +#endif |
| __flush_tlb_all(); |
| |
| if (!after_bootmem && e820_table_end > e820_table_start) |
| --- a/arch/x86/mm/init_64.c |
| +++ b/arch/x86/mm/init_64.c |
| @@ -49,7 +49,6 @@ |
| #include <asm/numa.h> |
| #include <asm/cacheflush.h> |
| #include <asm/init.h> |
| -#include <asm/setup.h> |
| #include <linux/bootmem.h> |
| |
| static unsigned long dma_reserve __initdata; |
| @@ -258,18 +257,18 @@ void __init init_extra_mapping_uc(unsign |
| * to the compile time generated pmds. This results in invalid pmds up |
| * to the point where we hit the physaddr 0 mapping. |
| * |
| - * We limit the mappings to the region from _text to _brk_end. _brk_end |
| - * is rounded up to the 2MB boundary. This catches the invalid pmds as |
| + * We limit the mappings to the region from _text to _end. _end is |
| + * rounded up to the 2MB boundary. This catches the invalid pmds as |
| * well, as they are located before _text: |
| */ |
| void __init cleanup_highmap(void) |
| { |
| unsigned long vaddr = __START_KERNEL_map; |
| - unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT); |
| - unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; |
| + unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1; |
| pmd_t *pmd = level2_kernel_pgt; |
| + pmd_t *last_pmd = pmd + PTRS_PER_PMD; |
| |
| - for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) { |
| + for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) { |
| if (pmd_none(*pmd)) |
| continue; |
| if (vaddr < (unsigned long) _text || vaddr > end) |