 8866cd9dc9
			
		
	
	
	8866cd9dc9
	
	
	
		
			
			It's not too pretty, but I found this made the "PANIC: early exception" messages become much more reliably useful: 1. print the vector number, 2. print the %cs value, 3. handle error-code-pushing vs non-pushing vectors. Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
		
			
				
	
	
		
			204 lines
		
	
	
	
		
			5.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			204 lines
		
	
	
	
		
			5.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _ASM_X86_SEGMENT_H_
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| #define _ASM_X86_SEGMENT_H_
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| 
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| /* Simple and small GDT entries for booting only */
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| 
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| #define GDT_ENTRY_BOOT_CS	2
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| #define __BOOT_CS		(GDT_ENTRY_BOOT_CS * 8)
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| 
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| #define GDT_ENTRY_BOOT_DS	(GDT_ENTRY_BOOT_CS + 1)
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| #define __BOOT_DS		(GDT_ENTRY_BOOT_DS * 8)
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| 
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| #define GDT_ENTRY_BOOT_TSS	(GDT_ENTRY_BOOT_CS + 2)
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| #define __BOOT_TSS		(GDT_ENTRY_BOOT_TSS * 8)
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| 
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| #ifdef CONFIG_X86_32
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| /*
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|  * The layout of the per-CPU GDT under Linux:
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|  *
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|  *   0 - null
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|  *   1 - reserved
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|  *   2 - reserved
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|  *   3 - reserved
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|  *
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|  *   4 - unused			<==== new cacheline
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|  *   5 - unused
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|  *
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|  *  ------- start of TLS (Thread-Local Storage) segments:
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|  *
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|  *   6 - TLS segment #1			[ glibc's TLS segment ]
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|  *   7 - TLS segment #2			[ Wine's %fs Win32 segment ]
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|  *   8 - TLS segment #3
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|  *   9 - reserved
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|  *  10 - reserved
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|  *  11 - reserved
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|  *
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|  *  ------- start of kernel segments:
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|  *
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|  *  12 - kernel code segment		<==== new cacheline
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|  *  13 - kernel data segment
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|  *  14 - default user CS
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|  *  15 - default user DS
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|  *  16 - TSS
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|  *  17 - LDT
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|  *  18 - PNPBIOS support (16->32 gate)
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|  *  19 - PNPBIOS support
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|  *  20 - PNPBIOS support
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|  *  21 - PNPBIOS support
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|  *  22 - PNPBIOS support
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|  *  23 - APM BIOS support
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|  *  24 - APM BIOS support
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|  *  25 - APM BIOS support
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|  *
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|  *  26 - ESPFIX small SS
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|  *  27 - per-cpu			[ offset to per-cpu data area ]
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|  *  28 - unused
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|  *  29 - unused
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|  *  30 - unused
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|  *  31 - TSS for double fault handler
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|  */
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| #define GDT_ENTRY_TLS_MIN	6
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| #define GDT_ENTRY_TLS_MAX 	(GDT_ENTRY_TLS_MIN + GDT_ENTRY_TLS_ENTRIES - 1)
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| 
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| #define GDT_ENTRY_DEFAULT_USER_CS	14
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| #define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS * 8 + 3)
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| 
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| #define GDT_ENTRY_DEFAULT_USER_DS	15
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| #define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS * 8 + 3)
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| 
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| #define GDT_ENTRY_KERNEL_BASE	12
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| 
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| #define GDT_ENTRY_KERNEL_CS		(GDT_ENTRY_KERNEL_BASE + 0)
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| #define __KERNEL_CS (GDT_ENTRY_KERNEL_CS * 8)
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| 
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| #define GDT_ENTRY_KERNEL_DS		(GDT_ENTRY_KERNEL_BASE + 1)
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| #define __KERNEL_DS (GDT_ENTRY_KERNEL_DS * 8)
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| 
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| #define GDT_ENTRY_TSS			(GDT_ENTRY_KERNEL_BASE + 4)
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| #define GDT_ENTRY_LDT			(GDT_ENTRY_KERNEL_BASE + 5)
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| 
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| #define GDT_ENTRY_PNPBIOS_BASE		(GDT_ENTRY_KERNEL_BASE + 6)
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| #define GDT_ENTRY_APMBIOS_BASE		(GDT_ENTRY_KERNEL_BASE + 11)
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| 
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| #define GDT_ENTRY_ESPFIX_SS		(GDT_ENTRY_KERNEL_BASE + 14)
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| #define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS * 8)
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| 
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| #define GDT_ENTRY_PERCPU			(GDT_ENTRY_KERNEL_BASE + 15)
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| #ifdef CONFIG_SMP
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| #define __KERNEL_PERCPU (GDT_ENTRY_PERCPU * 8)
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| #else
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| #define __KERNEL_PERCPU 0
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| #endif
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| 
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| #define GDT_ENTRY_DOUBLEFAULT_TSS	31
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| 
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| /*
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|  * The GDT has 32 entries
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|  */
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| #define GDT_ENTRIES 32
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| 
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| /* The PnP BIOS entries in the GDT */
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| #define GDT_ENTRY_PNPBIOS_CS32		(GDT_ENTRY_PNPBIOS_BASE + 0)
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| #define GDT_ENTRY_PNPBIOS_CS16		(GDT_ENTRY_PNPBIOS_BASE + 1)
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| #define GDT_ENTRY_PNPBIOS_DS		(GDT_ENTRY_PNPBIOS_BASE + 2)
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| #define GDT_ENTRY_PNPBIOS_TS1		(GDT_ENTRY_PNPBIOS_BASE + 3)
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| #define GDT_ENTRY_PNPBIOS_TS2		(GDT_ENTRY_PNPBIOS_BASE + 4)
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| 
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| /* The PnP BIOS selectors */
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| #define PNP_CS32   (GDT_ENTRY_PNPBIOS_CS32 * 8)	/* segment for calling fn */
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| #define PNP_CS16   (GDT_ENTRY_PNPBIOS_CS16 * 8)	/* code segment for BIOS */
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| #define PNP_DS     (GDT_ENTRY_PNPBIOS_DS * 8)	/* data segment for BIOS */
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| #define PNP_TS1    (GDT_ENTRY_PNPBIOS_TS1 * 8)	/* transfer data segment */
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| #define PNP_TS2    (GDT_ENTRY_PNPBIOS_TS2 * 8)	/* another data segment */
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| 
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| /* Bottom two bits of selector give the ring privilege level */
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| #define SEGMENT_RPL_MASK	0x3
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| /* Bit 2 is table indicator (LDT/GDT) */
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| #define SEGMENT_TI_MASK		0x4
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| 
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| /* User mode is privilege level 3 */
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| #define USER_RPL		0x3
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| /* LDT segment has TI set, GDT has it cleared */
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| #define SEGMENT_LDT		0x4
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| #define SEGMENT_GDT		0x0
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| 
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| /*
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|  * Matching rules for certain types of segments.
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|  */
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| 
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| /* Matches only __KERNEL_CS, ignoring PnP / USER / APM segments */
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| #define SEGMENT_IS_KERNEL_CODE(x) (((x) & 0xfc) == GDT_ENTRY_KERNEL_CS * 8)
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| 
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| /* Matches __KERNEL_CS and __USER_CS (they must be 2 entries apart) */
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| #define SEGMENT_IS_FLAT_CODE(x)  (((x) & 0xec) == GDT_ENTRY_KERNEL_CS * 8)
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| 
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| /* Matches PNP_CS32 and PNP_CS16 (they must be consecutive) */
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| #define SEGMENT_IS_PNP_CODE(x)   (((x) & 0xf4) == GDT_ENTRY_PNPBIOS_BASE * 8)
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| 
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| 
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| #else
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| #include <asm/cache.h>
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| 
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| #define __KERNEL_CS	0x10
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| #define __KERNEL_DS	0x18
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| 
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| #define __KERNEL32_CS   0x08
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| 
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| /*
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|  * we cannot use the same code segment descriptor for user and kernel
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|  * -- not even in the long flat mode, because of different DPL /kkeil
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|  * The segment offset needs to contain a RPL. Grr. -AK
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|  * GDT layout to get 64bit syscall right (sysret hardcodes gdt offsets)
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|  */
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| 
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| #define __USER32_CS   0x23   /* 4*8+3 */
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| #define __USER_DS     0x2b   /* 5*8+3 */
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| #define __USER_CS     0x33   /* 6*8+3 */
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| #define __USER32_DS	__USER_DS
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| 
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| #define GDT_ENTRY_TSS 8	/* needs two entries */
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| #define GDT_ENTRY_LDT 10 /* needs two entries */
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| #define GDT_ENTRY_TLS_MIN 12
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| #define GDT_ENTRY_TLS_MAX 14
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| 
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| #define GDT_ENTRY_PER_CPU 15	/* Abused to load per CPU data from limit */
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| #define __PER_CPU_SEG	(GDT_ENTRY_PER_CPU * 8 + 3)
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| 
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| /* TLS indexes for 64bit - hardcoded in arch_prctl */
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| #define FS_TLS 0
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| #define GS_TLS 1
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| 
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| #define GS_TLS_SEL ((GDT_ENTRY_TLS_MIN+GS_TLS)*8 + 3)
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| #define FS_TLS_SEL ((GDT_ENTRY_TLS_MIN+FS_TLS)*8 + 3)
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| 
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| #define GDT_ENTRIES 16
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| 
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| #endif
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| 
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| #ifndef CONFIG_PARAVIRT
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| #define get_kernel_rpl()  0
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| #endif
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| 
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| /* User mode is privilege level 3 */
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| #define USER_RPL		0x3
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| /* LDT segment has TI set, GDT has it cleared */
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| #define SEGMENT_LDT		0x4
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| #define SEGMENT_GDT		0x0
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| 
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| /* Bottom two bits of selector give the ring privilege level */
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| #define SEGMENT_RPL_MASK	0x3
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| /* Bit 2 is table indicator (LDT/GDT) */
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| #define SEGMENT_TI_MASK		0x4
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| 
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| #define IDT_ENTRIES 256
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| #define GDT_SIZE (GDT_ENTRIES * 8)
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| #define GDT_ENTRY_TLS_ENTRIES 3
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| #define TLS_SIZE (GDT_ENTRY_TLS_ENTRIES * 8)
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| 
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| #ifdef __KERNEL__
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| #ifndef __ASSEMBLY__
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| extern const char early_idt_handlers[IDT_ENTRIES][10];
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| #endif
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| #endif
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| 
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| #endif
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