diff options
| -rw-r--r-- | arch/i386/kernel/ldt.c | 4 | ||||
| -rw-r--r-- | arch/i386/kernel/traps.c | 3 | ||||
| -rw-r--r-- | include/asm-i386/desc.h | 50 | ||||
| -rw-r--r-- | include/asm-i386/mmu_context.h | 4 |
4 files changed, 22 insertions, 39 deletions
diff --git a/arch/i386/kernel/ldt.c b/arch/i386/kernel/ldt.c index 445211eb2d5..b410e5fb034 100644 --- a/arch/i386/kernel/ldt.c +++ b/arch/i386/kernel/ldt.c @@ -160,16 +160,14 @@ static int read_default_ldt(void __user * ptr, unsigned long bytecount) { int err; unsigned long size; - void *address; err = 0; - address = &default_ldt[0]; size = 5*sizeof(struct desc_struct); if (size > bytecount) size = bytecount; err = size; - if (copy_to_user(ptr, address, size)) + if (clear_user(ptr, size)) err = -EFAULT; return err; diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c index 48ebfab661b..56655ea8d98 100644 --- a/arch/i386/kernel/traps.c +++ b/arch/i386/kernel/traps.c @@ -61,9 +61,6 @@ int panic_on_unrecovered_nmi; asmlinkage int system_call(void); -struct desc_struct default_ldt[] = { { 0, 0 }, { 0, 0 }, { 0, 0 }, - { 0, 0 }, { 0, 0 } }; - /* Do we ignore FPU interrupts ? */ char ignore_fpu_irq = 0; diff --git a/include/asm-i386/desc.h b/include/asm-i386/desc.h index 5874ef119ff..a0398f780ca 100644 --- a/include/asm-i386/desc.h +++ b/include/asm-i386/desc.h @@ -33,11 +33,6 @@ static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu) return (struct desc_struct *)per_cpu(cpu_gdt_descr, cpu).address; } -/* - * This is the ldt that every process will get unless we need - * something other than this. - */ -extern struct desc_struct default_ldt[]; extern struct desc_struct idt_table[]; extern void set_intr_gate(unsigned int irq, void * addr); @@ -65,7 +60,6 @@ static inline void pack_gate(__u32 *a, __u32 *b, #define DESCTYPE_S 0x10 /* !system */ #define load_TR_desc() __asm__ __volatile__("ltr %w0"::"q" (GDT_ENTRY_TSS*8)) -#define load_LDT_desc() __asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8)) #define load_gdt(dtr) __asm__ __volatile("lgdt %0"::"m" (*dtr)) #define load_idt(dtr) __asm__ __volatile("lidt %0"::"m" (*dtr)) @@ -115,13 +109,20 @@ static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, const vo write_gdt_entry(get_cpu_gdt_table(cpu), entry, a, b); } -static inline void set_ldt_desc(unsigned int cpu, void *addr, unsigned int entries) +static inline void set_ldt(void *addr, unsigned int entries) { - __u32 a, b; - pack_descriptor(&a, &b, (unsigned long)addr, - entries * sizeof(struct desc_struct) - 1, - DESCTYPE_LDT, 0); - write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT, a, b); + if (likely(entries == 0)) + __asm__ __volatile__("lldt %w0"::"q" (0)); + else { + unsigned cpu = smp_processor_id(); + __u32 a, b; + + pack_descriptor(&a, &b, (unsigned long)addr, + entries * sizeof(struct desc_struct) - 1, + DESCTYPE_LDT, 0); + write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT, a, b); + __asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8)); + } } #define set_tss_desc(cpu,addr) __set_tss_desc(cpu, GDT_ENTRY_TSS, addr) @@ -153,35 +154,22 @@ static inline void set_ldt_desc(unsigned int cpu, void *addr, unsigned int entri static inline void clear_LDT(void) { - int cpu = get_cpu(); - - set_ldt_desc(cpu, &default_ldt[0], 5); - load_LDT_desc(); - put_cpu(); + set_ldt(NULL, 0); } /* * load one particular LDT into the current CPU */ -static inline void load_LDT_nolock(mm_context_t *pc, int cpu) +static inline void load_LDT_nolock(mm_context_t *pc) { - void *segments = pc->ldt; - int count = pc->size; - - if (likely(!count)) { - segments = &default_ldt[0]; - count = 5; - } - - set_ldt_desc(cpu, segments, count); - load_LDT_desc(); + set_ldt(pc->ldt, pc->size); } static inline void load_LDT(mm_context_t *pc) { - int cpu = get_cpu(); - load_LDT_nolock(pc, cpu); - put_cpu(); + preempt_disable(); + load_LDT_nolock(pc); + preempt_enable(); } static inline unsigned long get_desc_base(unsigned long *desc) diff --git a/include/asm-i386/mmu_context.h b/include/asm-i386/mmu_context.h index 62b7bf18409..1b1495372c4 100644 --- a/include/asm-i386/mmu_context.h +++ b/include/asm-i386/mmu_context.h @@ -44,7 +44,7 @@ static inline void switch_mm(struct mm_struct *prev, * load the LDT, if the LDT is different: */ if (unlikely(prev->context.ldt != next->context.ldt)) - load_LDT_nolock(&next->context, cpu); + load_LDT_nolock(&next->context); } #ifdef CONFIG_SMP else { @@ -56,7 +56,7 @@ static inline void switch_mm(struct mm_struct *prev, * tlb flush IPI delivery. We must reload %cr3. */ load_cr3(next->pgd); - load_LDT_nolock(&next->context, cpu); + load_LDT_nolock(&next->context); } } #endif |