Commit 87cc0376 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Ingo Molnar
Browse files

x86/ldttss: Clean up 32-bit descriptors 



Like the IDT descriptors, the LDT/TSS descriptors are pointlessly different
on 32 and 64 bit kernels.

Unify them and get rid of the duplicated code.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064958.289634692@linutronix.de


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 38e9e81f

arch/x86/include/asm/desc.h

+3 −23
Original line number Diff line number Diff line
@@ -166,42 +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->limit0		= (u16) limit;

	desc->base0		= (u16) base;

	desc->base1		= (base >> 16) & 0xFF;

	desc->type		= type & 0x0F;

	desc->s			= 0;

	desc->dpl		= 0;

	desc->p			= 1;

	desc->limit1		= (limit >> 16) & 0xF;

	desc->avl		= (flags >> 0) & 0x01;

	desc->l			= (flags >> 1) & 0x01;

	desc->d			= (flags >> 2) & 0x01;

	desc->g			= (flags >> 3) & 0x01;

}



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->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		= (addr >> 24) & 0xFF;

#ifdef CONFIG_X86_64

	desc->base3		= (u32) (addr >> 32);

#else

	pack_descriptor((struct desc_struct *)d, addr, size, type, 0);

#endif

}

arch/x86/include/asm/desc_defs.h

+12 −15
Original line number Diff line number Diff line
@@ -49,24 +49,21 @@ enum { 
	DESCTYPE_S = 0x10,	/* !system */

};



/* LDT or TSS descriptor in the GDT. 16 bytes. */

struct ldttss_desc64 {

/* LDT or TSS descriptor in the GDT. */

struct ldttss_desc {

	u16	limit0;

	u16	base0;

	unsigned base1 : 8, type : 5, dpl : 2, p : 1;

	unsigned limit1 : 4, zero0 : 3, g : 1, base2 : 8;



	u16	base1 : 8, type : 5, dpl : 2, p : 1;

	u16	limit1 : 4, zero0 : 3, g : 1, base2 : 8;

#ifdef CONFIG_X86_64

	u32	base3;

	u32	zero1;

#endif

} __attribute__((packed));





#ifdef CONFIG_X86_64

typedef struct ldttss_desc64 ldt_desc;

typedef struct ldttss_desc64 tss_desc;

#else

typedef struct desc_struct ldt_desc;

typedef struct desc_struct tss_desc;

#endif

typedef struct ldttss_desc ldt_desc;

typedef struct ldttss_desc tss_desc;



struct idt_bits {

	u16		ist	: 3,

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