Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933516Ab1CZAGs (ORCPT ); Fri, 25 Mar 2011 20:06:48 -0400 Received: from kroah.org ([198.145.64.141]:35962 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933485Ab1CZAGp (ORCPT ); Fri, 25 Mar 2011 20:06:45 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Mar 25 17:04:59 2011 Message-Id: <20110326000459.189962134@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 25 Mar 2011 17:04:04 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Yinghai Lu , Stefano Stabellini , "H. Peter Anvin" Subject: [32/35] x86: Cleanup highmap after brk is concluded In-Reply-To: <20110326000509.GA29736@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4490 Lines: 135 2.6.33-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Yinghai Lu commit e5f15b45ddf3afa2bbbb10c7ea34fb32b6de0a0e upstream. Now cleanup_highmap actually is in two steps: one is early in head64.c and only clears above _end; a second one is in init_memory_mapping() and tries to clean from _brk_end to _end. It should check if those boundaries are PMD_SIZE aligned but currently does not. Also init_memory_mapping() is called several times for numa or memory hotplug, so we really should not handle initial kernel mappings there. This patch moves cleanup_highmap() down after _brk_end is settled so we can do everything in one step. Also we honor max_pfn_mapped in the implementation of cleanup_highmap. Signed-off-by: Yinghai Lu Signed-off-by: Stefano Stabellini LKML-Reference: Signed-off-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- 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, 11 insertions(+), 27 deletions(-) --- a/arch/x86/kernel/head64.c +++ b/arch/x86/kernel/head64.c @@ -76,9 +76,6 @@ 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 @@ -295,6 +295,9 @@ 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) @@ -895,6 +898,8 @@ void __init setup_arch(char **cmdline_p) reserve_brk(); + cleanup_highmap(); + /* * Find and reserve possible boot-time SMP configuration: */ --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -283,25 +283,6 @@ 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 @@ -49,6 +49,7 @@ #include #include #include +#include #include static unsigned long dma_reserve __initdata; @@ -257,18 +258,18 @@ 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 _end. _end is - * rounded up to the 2MB boundary. This catches the invalid pmds as + * 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 * well, as they are located before _text: */ void __init cleanup_highmap(void) { unsigned long vaddr = __START_KERNEL_map; - unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1; + unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT); + unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1; pmd_t *pmd = level2_kernel_pgt; - pmd_t *last_pmd = pmd + PTRS_PER_PMD; - for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) { + for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) { if (pmd_none(*pmd)) continue; if (vaddr < (unsigned long) _text || vaddr > end) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/