From f95190b28daa1bebf78ab5ec4129d01a223982c5 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Wed, 11 Jan 2006 22:44:00 +0100 Subject: [PATCH] [PATCH] x86_64: Remove unnecessary case from the page fault handler Don't need to do the vmalloc check for the module range because its PML4 is shared with the kernel text. Also removed an unnecessary TLB flush. Pointed out by Jan Beulich Cc: jbeulich@novell.com Signed-off-by: Andi Kleen Signed-off-by: Linus Torvalds --- arch/x86_64/mm/fault.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c index fd07b86c062d..2a9c836133a9 100644 --- a/arch/x86_64/mm/fault.c +++ b/arch/x86_64/mm/fault.c @@ -237,7 +237,7 @@ static noinline void pgtable_bad(unsigned long address, struct pt_regs *regs, } /* - * Handle a fault on the vmalloc or module mapping area + * Handle a fault on the vmalloc area * * This assumes no large pages in there. */ @@ -283,7 +283,6 @@ static int vmalloc_fault(unsigned long address) that. */ if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref)) BUG(); - __flush_tlb_all(); return 0; } @@ -346,9 +345,13 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, * protection error (error_code & 9) == 0. */ if (unlikely(address >= TASK_SIZE64)) { + /* + * Don't check for the module range here: its PML4 + * is always initialized because it's shared with the main + * kernel text. Only vmalloc may need PML4 syncups. + */ if (!(error_code & 0xd) && - ((address >= VMALLOC_START && address < VMALLOC_END) || - (address >= MODULES_VADDR && address < MODULES_END))) { + ((address >= VMALLOC_START && address < VMALLOC_END))) { if (vmalloc_fault(address) < 0) goto bad_area_nosemaphore; return; -- 2.20.1