diff --git a/arch/i386/kernel/apm.c b/arch/i386/kernel/apm.c
index 1e60acbed3c1468189d6323437a03420383deb25..6c8e483ce9e40af033e3cbc063db9442c90b3a75 100644
--- a/arch/i386/kernel/apm.c
+++ b/arch/i386/kernel/apm.c
@@ -2317,6 +2317,8 @@ static int __init apm_init(void)
for (i = 0; i < NR_CPUS; i++) {
struct desc_struct *gdt = get_cpu_gdt_table(i);
+ if (!gdt)
+ continue;
set_base(gdt[APM_CS >> 3],
__va((unsigned long)apm_info.bios.cseg << 4));
set_base(gdt[APM_CS_16 >> 3],
diff --git a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c
index 31e344b26bae824f255baa1446980486d8aff52a..cbc32069683f9bc3a2e516e37da88285e833385e 100644
--- a/arch/i386/kernel/cpu/common.c
+++ b/arch/i386/kernel/cpu/common.c
@@ -18,9 +18,6 @@
#include "cpu.h"
-DEFINE_PER_CPU(struct desc_struct, cpu_gdt_table[GDT_ENTRIES]);
-EXPORT_PER_CPU_SYMBOL(cpu_gdt_table);
-
DEFINE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
diff --git a/arch/i386/kernel/head.S b/arch/i386/kernel/head.S
index e437fb367498c029ea21f5a7d5495d6b965a70cd..870f20bf33c83325988b28b7343e6464aada4388 100644
--- a/arch/i386/kernel/head.S
+++ b/arch/i386/kernel/head.S
@@ -525,3 +525,5 @@ ENTRY(cpu_gdt_table)
.quad 0x0000000000000000 /* 0xf0 - unused */
.quad 0x0000000000000000 /* 0xf8 - GDT entry 31: double-fault TSS */
+ /* Be sure this is zeroed to avoid false validations in Xen */
+ .fill PAGE_SIZE_asm / 8 - GDT_ENTRIES,8,0
diff --git a/arch/i386/kernel/i386_ksyms.c b/arch/i386/kernel/i386_ksyms.c
index 180f070d03cbe205f50ebaf0828c26755e3320b9..3999bec50c33d4aceb332d355a0bba15ddfaf3de 100644
--- a/arch/i386/kernel/i386_ksyms.c
+++ b/arch/i386/kernel/i386_ksyms.c
@@ -3,8 +3,7 @@
#include <asm/checksum.h>
#include <asm/desc.h>
-/* This is definitely a GPL-only symbol */
-EXPORT_SYMBOL_GPL(cpu_gdt_table);
+EXPORT_SYMBOL_GPL(cpu_gdt_descr);
EXPORT_SYMBOL(__down_failed);
EXPORT_SYMBOL(__down_failed_interruptible);
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index 9ed449af8e9fdd350a42ff2c606c0af154dad875..b3c2e2c26743381e5f1a8b3dfd592c2c0cb5d2c9 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -903,6 +903,12 @@ static int __devinit do_boot_cpu(int apicid, int cpu)
unsigned long start_eip;
unsigned short nmi_high = 0, nmi_low = 0;
+ if (!cpu_gdt_descr[cpu].address &&
+ !(cpu_gdt_descr[cpu].address = get_zeroed_page(GFP_KERNEL))) {
+ printk("Failed to allocate GDT for CPU %d\n", cpu);
+ return 1;
+ }
+
++cpucount;
/*
diff --git a/drivers/pnp/pnpbios/bioscalls.c b/drivers/pnp/pnpbios/bioscalls.c
index 6b7583f497d0a36f2862806c65e23c80f5ee52c6..7cb476ed7f9183a0ef54fe2fec241b4fab93960b 100644
--- a/drivers/pnp/pnpbios/bioscalls.c
+++ b/drivers/pnp/pnpbios/bioscalls.c
@@ -69,14 +69,16 @@ __asm__(
#define Q_SET_SEL(cpu, selname, address, size) \
do { \
-set_base(per_cpu(cpu_gdt_table,cpu)[(selname) >> 3], __va((u32)(address))); \
-set_limit(per_cpu(cpu_gdt_table,cpu)[(selname) >> 3], size); \
+struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
+set_base(gdt[(selname) >> 3], __va((u32)(address))); \
+set_limit(gdt[(selname) >> 3], size); \
} while(0)
#define Q2_SET_SEL(cpu, selname, address, size) \
do { \
-set_base(per_cpu(cpu_gdt_table,cpu)[(selname) >> 3], (u32)(address)); \
-set_limit(per_cpu(cpu_gdt_table,cpu)[(selname) >> 3], size); \
+struct desc_struct *gdt = get_cpu_gdt_table((cpu)); \
+set_base(gdt[(selname) >> 3], (u32)(address)); \
+set_limit(gdt[(selname) >> 3], size); \
} while(0)
static struct desc_struct bad_bios_desc = { 0, 0x00409200 };
@@ -115,8 +117,8 @@ static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
return PNP_FUNCTION_NOT_SUPPORTED;
cpu = get_cpu();
- save_desc_40 = per_cpu(cpu_gdt_table,cpu)[0x40 / 8];
- per_cpu(cpu_gdt_table,cpu)[0x40 / 8] = bad_bios_desc;
+ save_desc_40 = get_cpu_gdt_table(cpu)[0x40 / 8];
+ get_cpu_gdt_table(cpu)[0x40 / 8] = bad_bios_desc;
/* On some boxes IRQ's during PnP BIOS calls are deadly. */
spin_lock_irqsave(&pnp_bios_lock, flags);
@@ -158,7 +160,7 @@ static inline u16 call_pnp_bios(u16 func, u16 arg1, u16 arg2, u16 arg3,
);
spin_unlock_irqrestore(&pnp_bios_lock, flags);
- per_cpu(cpu_gdt_table,cpu)[0x40 / 8] = save_desc_40;
+ get_cpu_gdt_table(cpu)[0x40 / 8] = save_desc_40;
put_cpu();
/* If we get here and this is set then the PnP BIOS faulted on us. */
@@ -535,8 +537,10 @@ void pnpbios_calls_init(union pnp_bios_install_struct *header)
set_base(bad_bios_desc, __va((unsigned long)0x40 << 4));
_set_limit((char *)&bad_bios_desc, 4095 - (0x40 << 4));
- for(i=0; i < NR_CPUS; i++)
- {
+ for (i = 0; i < NR_CPUS; i++) {
+ struct desc_struct *gdt = get_cpu_gdt_table(i);
+ if (!gdt)
+ continue;
Q2_SET_SEL(i, PNP_CS32, &pnp_bios_callfunc, 64 * 1024);
Q_SET_SEL(i, PNP_CS16, header->fields.pm16cseg, 64 * 1024);
Q_SET_SEL(i, PNP_DS, header->fields.pm16dseg, 64 * 1024);
diff --git a/include/asm-i386/desc.h b/include/asm-i386/desc.h
index 29b851a18c6ed6f0ba119f0ad5d727e3ae3a8c9f..494e73bca0956c2f327e0eaf07e1cb83752cf3bb 100644
--- a/include/asm-i386/desc.h
+++ b/include/asm-i386/desc.h
@@ -15,9 +15,6 @@
#include <asm/mmu.h>
extern struct desc_struct cpu_gdt_table[GDT_ENTRIES];
-DECLARE_PER_CPU(struct desc_struct, cpu_gdt_table[GDT_ENTRIES]);
-
-#define get_cpu_gdt_table(_cpu) (per_cpu(cpu_gdt_table,_cpu))
DECLARE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
@@ -29,6 +26,11 @@ struct Xgt_desc_struct {
extern struct Xgt_desc_struct idt_descr, cpu_gdt_descr[NR_CPUS];
+static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
+{
+ return ((struct desc_struct *)cpu_gdt_descr[cpu].address);
+}
+
#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))