Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 apic updates from Thomas Gleixner:
 "This update provides:

   - Cleanup of the IDT management including the removal of the extra
     tracing IDT. A first step to cleanup the vector management code.

   - The removal of the paravirt op adjust_exception_frame. This is a
     XEN specific issue, but merged through this branch to avoid nasty
     merge collisions

   - Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has
     disabled the TSC DEADLINE timer in CPUID.

   - Adjust a debug message in the ioapic code to print out the
     information correctly"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  x86/idt: Fix the X86_TRAP_BP gate
  x86/xen: Get rid of paravirt op adjust_exception_frame
  x86/eisa: Add missing include
  x86/idt: Remove superfluous ALIGNment
  x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
  x86/idt: Remove the tracing IDT leftovers
  x86/idt: Hide set_intr_gate()
  x86/idt: Simplify alloc_intr_gate()
  x86/idt: Deinline setup functions
  x86/idt: Remove unused functions/inlines
  x86/idt: Move interrupt gate initialization to IDT code
  x86/idt: Move APIC gate initialization to tables
  x86/idt: Move regular trap init to tables
  x86/idt: Move IST stack based traps to table init
  x86/idt: Move debug stack init to table based
  x86/idt: Switch early trap init to IDT tables
  x86/idt: Prepare for table based init
  x86/idt: Move early IDT setup out of 32-bit asm
  x86/idt: Move early IDT handler setup to IDT code
  x86/idt: Consolidate IDT invalidation
  ...

58 files changed, 901 insertions, 1077 deletions

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index e007887a33b0..926c2cc4facc 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -1058,7 +1058,7 @@ struct boot_params *efi_main(struct efi_config *c,
 		desc->s = DESC_TYPE_CODE_DATA;
 		desc->dpl = 0;
 		desc->p = 1;
-		desc->limit = 0xf;
+		desc->limit1 = 0xf;
 		desc->avl = 0;
 		desc->l = 0;
 		desc->d = SEG_OP_SIZE_32BIT;
@@ -1078,7 +1078,7 @@ struct boot_params *efi_main(struct efi_config *c,
 	desc->s = DESC_TYPE_CODE_DATA;
 	desc->dpl = 0;
 	desc->p = 1;
-	desc->limit = 0xf;
+	desc->limit1 = 0xf;
 	desc->avl = 0;
 	if (IS_ENABLED(CONFIG_X86_64)) {
 		desc->l = 1;
@@ -1099,7 +1099,7 @@ struct boot_params *efi_main(struct efi_config *c,
 	desc->s = DESC_TYPE_CODE_DATA;
 	desc->dpl = 0;
 	desc->p = 1;
-	desc->limit = 0xf;
+	desc->limit1 = 0xf;
 	desc->avl = 0;
 	desc->l = 0;
 	desc->d = SEG_OP_SIZE_32BIT;
@@ -1116,7 +1116,7 @@ struct boot_params *efi_main(struct efi_config *c,
 		desc->s = 0;
 		desc->dpl = 0;
 		desc->p = 1;
-		desc->limit = 0x0;
+		desc->limit1 = 0x0;
 		desc->avl = 0;
 		desc->l = 0;
 		desc->d = 0;
diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S
index 48ef7bb32c42..8a13d468635a 100644
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -673,16 +673,8 @@ ENTRY(name)				\
 	jmp	ret_from_intr;		\
 ENDPROC(name)
 
-
-#ifdef CONFIG_TRACING
-# define TRACE_BUILD_INTERRUPT(name, nr)	BUILD_INTERRUPT3(trace_##name, nr, smp_trace_##name)
-#else
-# define TRACE_BUILD_INTERRUPT(name, nr)
-#endif
-
 #define BUILD_INTERRUPT(name, nr)		\
 	BUILD_INTERRUPT3(name, nr, smp_##name);	\
-	TRACE_BUILD_INTERRUPT(name, nr)
 
 /* The include is where all of the SMP etc. interrupts come from */
 #include <asm/entry_arch.h>
@@ -880,25 +872,17 @@ ENTRY(xen_failsafe_callback)
 ENDPROC(xen_failsafe_callback)
 
 BUILD_INTERRUPT3(xen_hvm_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
-		xen_evtchn_do_upcall)
+		 xen_evtchn_do_upcall)
 
 #endif /* CONFIG_XEN */
 
 #if IS_ENABLED(CONFIG_HYPERV)
 
 BUILD_INTERRUPT3(hyperv_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
-	hyperv_vector_handler)
+		 hyperv_vector_handler)
 
 #endif /* CONFIG_HYPERV */
 
-#ifdef CONFIG_TRACING
-ENTRY(trace_page_fault)
-	ASM_CLAC
-	pushl	$trace_do_page_fault
-	jmp	common_exception
-END(trace_page_fault)
-#endif
-
 ENTRY(page_fault)
 	ASM_CLAC
 	pushl	$do_page_fault
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index ca0b250eefc4..49167258d587 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -748,18 +748,6 @@ ENTRY(\sym)
 END(\sym)
 .endm
 
-#ifdef CONFIG_TRACING
-#define trace(sym) trace_##sym
-#define smp_trace(sym) smp_trace_##sym
-
-.macro trace_apicinterrupt num sym
-apicinterrupt3 \num trace(\sym) smp_trace(\sym)
-.endm
-#else
-.macro trace_apicinterrupt num sym do_sym
-.endm
-#endif
-
 /* Make sure APIC interrupt handlers end up in the irqentry section: */
 #define PUSH_SECTION_IRQENTRY	.pushsection .irqentry.text, "ax"
 #define POP_SECTION_IRQENTRY	.popsection
@@ -767,7 +755,6 @@ apicinterrupt3 \num trace(\sym) smp_trace(\sym)
 .macro apicinterrupt num sym do_sym
 PUSH_SECTION_IRQENTRY
 apicinterrupt3 \num \sym \do_sym
-trace_apicinterrupt \num \sym
 POP_SECTION_IRQENTRY
 .endm
 
@@ -829,7 +816,6 @@ ENTRY(\sym)
 	.endif
 
 	ASM_CLAC
-	PARAVIRT_ADJUST_EXCEPTION_FRAME
 
 	.ifeq \has_error_code
 	pushq	$-1				/* ORIG_RAX: no syscall to restart */
@@ -913,17 +899,6 @@ ENTRY(\sym)
 END(\sym)
 .endm
 
-#ifdef CONFIG_TRACING
-.macro trace_idtentry sym do_sym has_error_code:req
-idtentry trace(\sym) trace(\do_sym) has_error_code=\has_error_code
-idtentry \sym \do_sym has_error_code=\has_error_code
-.endm
-#else
-.macro trace_idtentry sym do_sym has_error_code:req
-idtentry \sym \do_sym has_error_code=\has_error_code
-.endm
-#endif
-
 idtentry divide_error			do_divide_error			has_error_code=0
 idtentry overflow			do_overflow			has_error_code=0
 idtentry bounds				do_bounds			has_error_code=0
@@ -986,7 +961,7 @@ ENTRY(do_softirq_own_stack)
 ENDPROC(do_softirq_own_stack)
 
 #ifdef CONFIG_XEN
-idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
+idtentry hypervisor_callback xen_do_hypervisor_callback has_error_code=0
 
 /*
  * A note on the "critical region" in our callback handler.
@@ -1053,8 +1028,6 @@ ENTRY(xen_failsafe_callback)
 	movq	8(%rsp), %r11
 	addq	$0x30, %rsp
 	pushq	$0				/* RIP */
-	pushq	%r11
-	pushq	%rcx
 	UNWIND_HINT_IRET_REGS offset=8
 	jmp	general_protection
 1:	/* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */
@@ -1085,13 +1058,12 @@ idtentry int3			do_int3			has_error_code=0	paranoid=1 shift_ist=DEBUG_STACK
 idtentry stack_segment		do_stack_segment	has_error_code=1
 
 #ifdef CONFIG_XEN
-idtentry xen_debug		do_debug		has_error_code=0
-idtentry xen_int3		do_int3			has_error_code=0
-idtentry xen_stack_segment	do_stack_segment	has_error_code=1
+idtentry xendebug		do_debug		has_error_code=0
+idtentry xenint3		do_int3			has_error_code=0
 #endif
 
 idtentry general_protection	do_general_protection	has_error_code=1
-trace_idtentry page_fault	do_page_fault		has_error_code=1
+idtentry page_fault		do_page_fault		has_error_code=1
 
 #ifdef CONFIG_KVM_GUEST
 idtentry async_page_fault	do_async_page_fault	has_error_code=1
@@ -1251,21 +1223,10 @@ ENTRY(error_exit)
 END(error_exit)
 
 /* Runs on exception stack */
+/* XXX: broken on Xen PV */
 ENTRY(nmi)
 	UNWIND_HINT_IRET_REGS
 	/*
-	 * Fix up the exception frame if we're on Xen.
-	 * PARAVIRT_ADJUST_EXCEPTION_FRAME is guaranteed to push at most
-	 * one value to the stack on native, so it may clobber the rdx
-	 * scratch slot, but it won't clobber any of the important
-	 * slots past it.
-	 *
-	 * Xen is a different story, because the Xen frame itself overlaps
-	 * the "NMI executing" variable.
-	 */
-	PARAVIRT_ADJUST_EXCEPTION_FRAME
-
-	/*
 	 * We allow breakpoints in NMIs. If a breakpoint occurs, then
 	 * the iretq it performs will take us out of NMI context.
 	 * This means that we can have nested NMIs where the next
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 4b86d8da3ea3..e26c25ca7756 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -293,7 +293,6 @@ ENTRY(entry_INT80_compat)
 	/*
 	 * Interrupts are off on entry.
 	 */
-	PARAVIRT_ADJUST_EXCEPTION_FRAME
 	ASM_CLAC			/* Do this early to minimize exposure */
 	SWAPGS
 
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 726355ce8497..1911310959f8 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -351,7 +351,7 @@ static void vgetcpu_cpu_init(void *arg)
 	 * and 8 bits for the node)
 	 */
 	d.limit0 = cpu | ((node & 0xf) << 12);
-	d.limit = node >> 4;
+	d.limit1 = node >> 4;
 	d.type = 5;		/* RO data, expand down, accessed */
 	d.dpl = 3;		/* Visible to user code */
 	d.s = 1;		/* Not a system segment */
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
index d0a21b12dd58..1a2ba368da39 100644
--- a/arch/x86/include/asm/desc.h
+++ b/arch/x86/include/asm/desc.h
@@ -5,6 +5,7 @@
 #include <asm/ldt.h>
 #include <asm/mmu.h>
 #include <asm/fixmap.h>
+#include <asm/irq_vectors.h>
 
 #include <linux/smp.h>
 #include <linux/percpu.h>
@@ -22,7 +23,7 @@ static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *in
 	desc->s			= 1;
 	desc->dpl		= 0x3;
 	desc->p			= info->seg_not_present ^ 1;
-	desc->limit		= (info->limit & 0xf0000) >> 16;
+	desc->limit1		= (info->limit & 0xf0000) >> 16;
 	desc->avl		= info->useable;
 	desc->d			= info->seg_32bit;
 	desc->g			= info->limit_in_pages;
@@ -83,33 +84,25 @@ static inline phys_addr_t get_cpu_gdt_paddr(unsigned int cpu)
 	return per_cpu_ptr_to_phys(get_cpu_gdt_rw(cpu));
 }
 
-#ifdef CONFIG_X86_64
-
 static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,
 			     unsigned dpl, unsigned ist, unsigned seg)
 {
-	gate->offset_low	= PTR_LOW(func);
+	gate->offset_low	= (u16) func;
+	gate->bits.p		= 1;
+	gate->bits.dpl		= dpl;
+	gate->bits.zero		= 0;
+	gate->bits.type		= type;
+	gate->offset_middle	= (u16) (func >> 16);
+#ifdef CONFIG_X86_64
 	gate->segment		= __KERNEL_CS;
-	gate->ist		= ist;
-	gate->p			= 1;
-	gate->dpl		= dpl;
-	gate->zero0		= 0;
-	gate->zero1		= 0;
-	gate->type		= type;
-	gate->offset_middle	= PTR_MIDDLE(func);
-	gate->offset_high	= PTR_HIGH(func);
-}
-
+	gate->bits.ist		= ist;
+	gate->reserved		= 0;
+	gate->offset_high	= (u32) (func >> 32);
 #else
-static inline void pack_gate(gate_desc *gate, unsigned char type,
-			     unsigned long base, unsigned dpl, unsigned flags,
-			     unsigned short seg)
-{
-	gate->a = (seg << 16) | (base & 0xffff);
-	gate->b = (base & 0xffff0000) | (((0x80 | type | (dpl << 5)) & 0xff) << 8);
-}
-
+	gate->segment		= seg;
+	gate->bits.ist		= 0;
 #endif
+}
 
 static inline int desc_empty(const void *ptr)
 {
@@ -173,35 +166,22 @@ native_write_gdt_entry(struct desc_struct *gdt, int entry, const void *desc, int
 	memcpy(&gdt[entry], desc, size);
 }
 
-static inline void pack_descriptor(struct desc_struct *desc, unsigned long base,
-				   unsigned long limit, unsigned char type,
-				   unsigned char flags)
-{
-	desc->a = ((base & 0xffff) << 16) | (limit & 0xffff);
-	desc->b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
-		(limit & 0x000f0000) | ((type & 0xff) << 8) |
-		((flags & 0xf) << 20);
-	desc->p = 1;
-}
-
-
-static inline void set_tssldt_descriptor(void *d, unsigned long addr, unsigned type, unsigned size)
+static inline void set_tssldt_descriptor(void *d, unsigned long addr,
+					 unsigned type, unsigned size)
 {
-#ifdef CONFIG_X86_64
-	struct ldttss_desc64 *desc = d;
+	struct ldttss_desc *desc = d;
 
 	memset(desc, 0, sizeof(*desc));
 
-	desc->limit0		= size & 0xFFFF;
-	desc->base0		= PTR_LOW(addr);
-	desc->base1		= PTR_MIDDLE(addr) & 0xFF;
+	desc->limit0		= (u16) size;
+	desc->base0		= (u16) addr;
+	desc->base1		= (addr >> 16) & 0xFF;
 	desc->type		= type;
 	desc->p			= 1;
 	desc->limit1		= (size >> 16) & 0xF;
-	desc->base2		= (PTR_MIDDLE(addr) >> 8) & 0xFF;
-	desc->base3		= PTR_HIGH(addr);
-#else
-	pack_descriptor((struct desc_struct *)d, addr, size, 0x80 | type, 0);
+	desc->base2		= (addr >> 24) & 0xFF;
+#ifdef CONFIG_X86_64
+	desc->base3		= (u32) (addr >> 32);
 #endif
 }
 
@@ -401,147 +381,20 @@ static inline void set_desc_base(struct desc_struct *desc, unsigned long base)
 
 static inline unsigned long get_desc_limit(const struct desc_struct *desc)
 {
-	return desc->limit0 | (desc->limit << 16);
+	return desc->limit0 | (desc->limit1 << 16);
 }
 
 static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit)
 {
 	desc->limit0 = limit & 0xffff;
-	desc->limit = (limit >> 16) & 0xf;
-}
-
-#ifdef CONFIG_X86_64
-static inline void set_nmi_gate(int gate, void *addr)
-{
-	gate_desc s;
-
-	pack_gate(&s, GATE_INTERRUPT, (unsigned long)addr, 0, 0, __KERNEL_CS);
-	write_idt_entry(debug_idt_table, gate, &s);
+	desc->limit1 = (limit >> 16) & 0xf;
 }
-#endif
 
-#ifdef CONFIG_TRACING
-extern struct desc_ptr trace_idt_descr;
-extern gate_desc trace_idt_table[];
-static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
-{
-	write_idt_entry(trace_idt_table, entry, gate);
-}
+void update_intr_gate(unsigned int n, const void *addr);
+void alloc_intr_gate(unsigned int n, const void *addr);
 
-static inline void _trace_set_gate(int gate, unsigned type, void *addr,
-				   unsigned dpl, unsigned ist, unsigned seg)
-{
-	gate_desc s;
-
-	pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
-	/*
-	 * does not need to be atomic because it is only done once at
-	 * setup time
-	 */
-	write_trace_idt_entry(gate, &s);
-}
-#else
-static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
-{
-}
-
-#define _trace_set_gate(gate, type, addr, dpl, ist, seg)
-#endif
-
-static inline void _set_gate(int gate, unsigned type, void *addr,
-			     unsigned dpl, unsigned ist, unsigned seg)
-{
-	gate_desc s;
-
-	pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
-	/*
-	 * does not need to be atomic because it is only done once at
-	 * setup time
-	 */
-	write_idt_entry(idt_table, gate, &s);
-	write_trace_idt_entry(gate, &s);
-}
-
-/*
- * This needs to use 'idt_table' rather than 'idt', and
- * thus use the _nonmapped_ version of the IDT, as the
- * Pentium F0 0F bugfix can have resulted in the mapped
- * IDT being write-protected.
- */
-#define set_intr_gate_notrace(n, addr)					\
-	do {								\
-		BUG_ON((unsigned)n > 0xFF);				\
-		_set_gate(n, GATE_INTERRUPT, (void *)addr, 0, 0,	\
-			  __KERNEL_CS);					\
-	} while (0)
-
-#define set_intr_gate(n, addr)						\
-	do {								\
-		set_intr_gate_notrace(n, addr);				\
-		_trace_set_gate(n, GATE_INTERRUPT, (void *)trace_##addr,\
-				0, 0, __KERNEL_CS);			\
-	} while (0)
-
-extern int first_system_vector;
-/* used_vectors is BITMAP for irq is not managed by percpu vector_irq */
 extern unsigned long used_vectors[];
 
-static inline void alloc_system_vector(int vector)
-{
-	if (!test_bit(vector, used_vectors)) {
-		set_bit(vector, used_vectors);
-		if (first_system_vector > vector)
-			first_system_vector = vector;
-	} else {
-		BUG();
-	}
-}
-
-#define alloc_intr_gate(n, addr)				\
-	do {							\
-		alloc_system_vector(n);				\
-		set_intr_gate(n, addr);				\
-	} while (0)
-
-/*
- * This routine sets up an interrupt gate at directory privilege level 3.
- */
-static inline void set_system_intr_gate(unsigned int n, void *addr)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_INTERRUPT, addr, 0x3, 0, __KERNEL_CS);
-}
-
-static inline void set_system_trap_gate(unsigned int n, void *addr)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_TRAP, addr, 0x3, 0, __KERNEL_CS);
-}
-
-static inline void set_trap_gate(unsigned int n, void *addr)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_TRAP, addr, 0, 0, __KERNEL_CS);
-}
-
-static inline void set_task_gate(unsigned int n, unsigned int gdt_entry)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_TASK, (void *)0, 0, 0, (gdt_entry<<3));
-}
-
-static inline void set_intr_gate_ist(int n, void *addr, unsigned ist)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_INTERRUPT, addr, 0, ist, __KERNEL_CS);
-}
-
-static inline void set_system_intr_gate_ist(int n, void *addr, unsigned ist)
-{
-	BUG_ON((unsigned)n > 0xFF);
-	_set_gate(n, GATE_INTERRUPT, addr, 0x3, ist, __KERNEL_CS);
-}
-
 #ifdef CONFIG_X86_64
 DECLARE_PER_CPU(u32, debug_idt_ctr);
 static inline bool is_debug_idt_enabled(void)
@@ -567,31 +420,6 @@ static inline void load_debug_idt(void)
 }
 #endif
 
-#ifdef CONFIG_TRACING
-extern atomic_t trace_idt_ctr;
-static inline bool is_trace_idt_enabled(void)
-{
-	if (atomic_read(&trace_idt_ctr))
-		return true;
-
-	return false;
-}
-
-static inline void load_trace_idt(void)
-{
-	load_idt((const struct desc_ptr *)&trace_idt_descr);
-}
-#else
-static inline bool is_trace_idt_enabled(void)
-{
-	return false;
-}
-
-static inline void load_trace_idt(void)
-{
-}
-#endif
-
 /*
  * The load_current_idt() must be called with interrupts disabled
  * to avoid races. That way the IDT will always be set back to the expected
@@ -603,9 +431,25 @@ static inline void load_current_idt(void)
 {
 	if (is_debug_idt_enabled())
 		load_debug_idt();
-	else if (is_trace_idt_enabled())
-		load_trace_idt();
 	else
 		load_idt((const struct desc_ptr *)&idt_descr);
 }
+
+extern void idt_setup_early_handler(void);
+extern void idt_setup_early_traps(void);
+extern void idt_setup_traps(void);
+extern void idt_setup_apic_and_irq_gates(void);
+
+#ifdef CONFIG_X86_64
+extern void idt_setup_early_pf(void);
+extern void idt_setup_ist_traps(void);
+extern void idt_setup_debugidt_traps(void);
+#else
+static inline void idt_setup_early_pf(void) { }
+static inline void idt_setup_ist_traps(void) { }
+static inline void idt_setup_debugidt_traps(void) { }
+#endif
+
+extern void idt_invalidate(void *addr);
+
 #endif /* _ASM_X86_DESC_H */
diff --git a/arch/x86/include/asm/desc_defs.h b/arch/x86/include/asm/desc_defs.h
index 49265345d4d2..346d252029b7 100644
--- a/arch/x86/include/asm/desc_defs.h
+++ b/arch/x86/include/asm/desc_defs.h
@@ -11,34 +11,30 @@
 
 #include <linux/types.h>
 
-/*
- * FIXME: Accessing the desc_struct through its fields is more elegant,
- * and should be the one valid thing to do. However, a lot of open code
- * still touches the a and b accessors, and doing this allow us to do it
- * incrementally. We keep the signature as a struct, rather than a union,
- * so we can get rid of it transparently in the future -- glommer
- */
 /* 8 byte segment descriptor */
 struct desc_struct {
-	union {
-		struct {
-			unsigned int a;
-			unsigned int b;
-		};
-		struct {
-			u16 limit0;
-			u16 base0;
-			unsigned base1: 8, type: 4, s: 1, dpl: 2, p: 1;
-			unsigned limit: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8;
-		};
-	};
+	u16	limit0;
+	u16	base0;
+	u16	base1: 8, type: 4, s: 1, dpl: 2, p: 1;
+	u16	limit1: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8;
 } __attribute__((packed));
 
-#define GDT_ENTRY_INIT(flags, base, limit) { { { \
-		.a = ((limit) & 0xffff) | (((base) & 0xffff) << 16), \
-		.b = (((base) & 0xff0000) >> 16) | (((flags) & 0xf0ff) << 8) | \
-			((limit) & 0xf0000) | ((base) & 0xff000000), \
-	} } }
+#define GDT_ENTRY_INIT(flags, base, limit)			\
+	{							\
+		.limit0		= (u16) (limit),		\
+		.limit1		= ((limit) >> 16) & 0x0F,	\
+		.base0		= (u16) (base),			\
+		.base1		= ((base) >> 16) & 0xFF,	\
+		.base2		= ((base) >> 24) & 0xFF,	\
+		.type		= (flags & 0x0f),		\
+		.s		= (flags >> 4) & 0x01,		\
+		.dpl		= (flags >> 5) & 0x03,		\
+		.p		= (flags >> 7) & 0x01,		\
+		.avl		= (flags >> 12) & 0x01,		\
+		.l		= (flags >> 13) & 0x01,		\
+		.d		= (flags >> 14) & 0x01,		\
+		.g		= (flags >> 15) & 0x01,		\
+	}
 
 enum {
 	GATE_INTERRUPT = 0xE,
@@ -47,49 +43,63 @@ enum {
 	GATE_TASK = 0x5,
 };
 
-/* 16byte gate */
-struct gate_struct64 {
-	u16 offset_low;
-	u16 segment;
-	unsigned ist : 3, zero0 : 5, type : 5, dpl : 2, p : 1;
-	u16 offset_middle;
-	u32 offset_high;
-	u32 zero1;
-} __attribute__((packed));
-
-#define PTR_LOW(x) ((unsigned long long)(x) & 0xFFFF)
-#define PTR_MIDDLE(x) (((unsigned long long)(x) >> 16) & 0xFFFF)
-#define PTR_HIGH(x) ((unsigned long long)(x) >> 32)
-
 enum {
 	DESC_TSS = 0x9,
 	DESC_LDT = 0x2,
 	DESCTYPE_S