diff options
Diffstat (limited to 'arch/x86/mm/cpu_entry_area.c')
| -rw-r--r-- | arch/x86/mm/cpu_entry_area.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/arch/x86/mm/cpu_entry_area.c b/arch/x86/mm/cpu_entry_area.c index 476d810639a8..12d7e7fb4efd 100644 --- a/arch/x86/mm/cpu_entry_area.c +++ b/arch/x86/mm/cpu_entry_area.c @@ -2,6 +2,8 @@ #include <linux/spinlock.h> #include <linux/percpu.h> +#include <linux/kallsyms.h> +#include <linux/kcore.h> #include <asm/cpu_entry_area.h> #include <asm/pgtable.h> @@ -27,8 +29,20 @@ EXPORT_SYMBOL(get_cpu_entry_area); void cea_set_pte(void *cea_vaddr, phys_addr_t pa, pgprot_t flags) { unsigned long va = (unsigned long) cea_vaddr; + pte_t pte = pfn_pte(pa >> PAGE_SHIFT, flags); - set_pte_vaddr(va, pfn_pte(pa >> PAGE_SHIFT, flags)); + /* + * The cpu_entry_area is shared between the user and kernel + * page tables. All of its ptes can safely be global. + * _PAGE_GLOBAL gets reused to help indicate PROT_NONE for + * non-present PTEs, so be careful not to set it in that + * case to avoid confusion. + */ + if (boot_cpu_has(X86_FEATURE_PGE) && + (pgprot_val(flags) & _PAGE_PRESENT)) + pte = pte_set_flags(pte, _PAGE_GLOBAL); + + set_pte_vaddr(va, pte); } static void __init @@ -68,8 +82,6 @@ static void percpu_setup_debug_store(int cpu) static void __init setup_cpu_entry_area(int cpu) { #ifdef CONFIG_X86_64 - extern char _entry_trampoline[]; - /* On 64-bit systems, we use a read-only fixmap GDT and TSS. */ pgprot_t gdt_prot = PAGE_KERNEL_RO; pgprot_t tss_prot = PAGE_KERNEL_RO; @@ -131,9 +143,6 @@ static void __init setup_cpu_entry_area(int cpu) cea_map_percpu_pages(&get_cpu_entry_area(cpu)->exception_stacks, &per_cpu(exception_stacks, cpu), sizeof(exception_stacks) / PAGE_SIZE, PAGE_KERNEL); - - cea_set_pte(&get_cpu_entry_area(cpu)->entry_trampoline, - __pa_symbol(_entry_trampoline), PAGE_KERNEL_RX); #endif percpu_setup_debug_store(cpu); } |