 801806d956
			
		
	
	
	801806d956
	
	
	
		
			
			The IRET instruction should clear NMI masking, but the current implementation does not do so. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
		
			
				
	
	
		
			428 lines
		
	
	
	
		
			14 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			428 lines
		
	
	
	
		
			14 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /******************************************************************************
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|  * x86_emulate.h
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|  *
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|  * Generic x86 (32-bit and 64-bit) instruction decoder and emulator.
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|  *
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|  * Copyright (c) 2005 Keir Fraser
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|  *
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|  * From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4
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|  */
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| 
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| #ifndef _ASM_X86_KVM_X86_EMULATE_H
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| #define _ASM_X86_KVM_X86_EMULATE_H
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| 
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| #include <asm/desc_defs.h>
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| 
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| struct x86_emulate_ctxt;
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| enum x86_intercept;
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| enum x86_intercept_stage;
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| 
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| struct x86_exception {
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| 	u8 vector;
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| 	bool error_code_valid;
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| 	u16 error_code;
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| 	bool nested_page_fault;
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| 	u64 address; /* cr2 or nested page fault gpa */
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| };
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| 
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| /*
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|  * This struct is used to carry enough information from the instruction
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|  * decoder to main KVM so that a decision can be made whether the
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|  * instruction needs to be intercepted or not.
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|  */
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| struct x86_instruction_info {
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| 	u8  intercept;          /* which intercept                      */
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| 	u8  rep_prefix;         /* rep prefix?                          */
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| 	u8  modrm_mod;		/* mod part of modrm			*/
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| 	u8  modrm_reg;          /* index of register used               */
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| 	u8  modrm_rm;		/* rm part of modrm			*/
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| 	u64 src_val;            /* value of source operand              */
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| 	u64 dst_val;            /* value of destination operand         */
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| 	u8  src_bytes;          /* size of source operand               */
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| 	u8  dst_bytes;          /* size of destination operand          */
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| 	u8  ad_bytes;           /* size of src/dst address              */
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| 	u64 next_rip;           /* rip following the instruction        */
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| };
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| 
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| /*
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|  * x86_emulate_ops:
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|  *
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|  * These operations represent the instruction emulator's interface to memory.
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|  * There are two categories of operation: those that act on ordinary memory
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|  * regions (*_std), and those that act on memory regions known to require
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|  * special treatment or emulation (*_emulated).
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|  *
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|  * The emulator assumes that an instruction accesses only one 'emulated memory'
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|  * location, that this location is the given linear faulting address (cr2), and
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|  * that this is one of the instruction's data operands. Instruction fetches and
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|  * stack operations are assumed never to access emulated memory. The emulator
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|  * automatically deduces which operand of a string-move operation is accessing
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|  * emulated memory, and assumes that the other operand accesses normal memory.
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|  *
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|  * NOTES:
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|  *  1. The emulator isn't very smart about emulated vs. standard memory.
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|  *     'Emulated memory' access addresses should be checked for sanity.
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|  *     'Normal memory' accesses may fault, and the caller must arrange to
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|  *     detect and handle reentrancy into the emulator via recursive faults.
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|  *     Accesses may be unaligned and may cross page boundaries.
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|  *  2. If the access fails (cannot emulate, or a standard access faults) then
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|  *     it is up to the memop to propagate the fault to the guest VM via
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|  *     some out-of-band mechanism, unknown to the emulator. The memop signals
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|  *     failure by returning X86EMUL_PROPAGATE_FAULT to the emulator, which will
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|  *     then immediately bail.
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|  *  3. Valid access sizes are 1, 2, 4 and 8 bytes. On x86/32 systems only
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|  *     cmpxchg8b_emulated need support 8-byte accesses.
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|  *  4. The emulator cannot handle 64-bit mode emulation on an x86/32 system.
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|  */
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| /* Access completed successfully: continue emulation as normal. */
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| #define X86EMUL_CONTINUE        0
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| /* Access is unhandleable: bail from emulation and return error to caller. */
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| #define X86EMUL_UNHANDLEABLE    1
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| /* Terminate emulation but return success to the caller. */
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| #define X86EMUL_PROPAGATE_FAULT 2 /* propagate a generated fault to guest */
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| #define X86EMUL_RETRY_INSTR     3 /* retry the instruction for some reason */
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| #define X86EMUL_CMPXCHG_FAILED  4 /* cmpxchg did not see expected value */
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| #define X86EMUL_IO_NEEDED       5 /* IO is needed to complete emulation */
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| #define X86EMUL_INTERCEPTED     6 /* Intercepted by nested VMCB/VMCS */
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| 
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| struct x86_emulate_ops {
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| 	/*
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| 	 * read_gpr: read a general purpose register (rax - r15)
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| 	 *
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| 	 * @reg: gpr number.
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| 	 */
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| 	ulong (*read_gpr)(struct x86_emulate_ctxt *ctxt, unsigned reg);
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| 	/*
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| 	 * write_gpr: write a general purpose register (rax - r15)
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| 	 *
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| 	 * @reg: gpr number.
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| 	 * @val: value to write.
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| 	 */
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| 	void (*write_gpr)(struct x86_emulate_ctxt *ctxt, unsigned reg, ulong val);
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| 	/*
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| 	 * read_std: Read bytes of standard (non-emulated/special) memory.
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| 	 *           Used for descriptor reading.
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| 	 *  @addr:  [IN ] Linear address from which to read.
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| 	 *  @val:   [OUT] Value read from memory, zero-extended to 'u_long'.
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| 	 *  @bytes: [IN ] Number of bytes to read from memory.
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| 	 */
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| 	int (*read_std)(struct x86_emulate_ctxt *ctxt,
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| 			unsigned long addr, void *val,
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| 			unsigned int bytes,
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| 			struct x86_exception *fault);
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| 
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| 	/*
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| 	 * write_std: Write bytes of standard (non-emulated/special) memory.
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| 	 *            Used for descriptor writing.
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| 	 *  @addr:  [IN ] Linear address to which to write.
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| 	 *  @val:   [OUT] Value write to memory, zero-extended to 'u_long'.
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| 	 *  @bytes: [IN ] Number of bytes to write to memory.
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| 	 */
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| 	int (*write_std)(struct x86_emulate_ctxt *ctxt,
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| 			 unsigned long addr, void *val, unsigned int bytes,
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| 			 struct x86_exception *fault);
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| 	/*
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| 	 * fetch: Read bytes of standard (non-emulated/special) memory.
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| 	 *        Used for instruction fetch.
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| 	 *  @addr:  [IN ] Linear address from which to read.
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| 	 *  @val:   [OUT] Value read from memory, zero-extended to 'u_long'.
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| 	 *  @bytes: [IN ] Number of bytes to read from memory.
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| 	 */
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| 	int (*fetch)(struct x86_emulate_ctxt *ctxt,
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| 		     unsigned long addr, void *val, unsigned int bytes,
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| 		     struct x86_exception *fault);
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| 
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| 	/*
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| 	 * read_emulated: Read bytes from emulated/special memory area.
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| 	 *  @addr:  [IN ] Linear address from which to read.
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| 	 *  @val:   [OUT] Value read from memory, zero-extended to 'u_long'.
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| 	 *  @bytes: [IN ] Number of bytes to read from memory.
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| 	 */
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| 	int (*read_emulated)(struct x86_emulate_ctxt *ctxt,
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| 			     unsigned long addr, void *val, unsigned int bytes,
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| 			     struct x86_exception *fault);
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| 
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| 	/*
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| 	 * write_emulated: Write bytes to emulated/special memory area.
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| 	 *  @addr:  [IN ] Linear address to which to write.
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| 	 *  @val:   [IN ] Value to write to memory (low-order bytes used as
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| 	 *                required).
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| 	 *  @bytes: [IN ] Number of bytes to write to memory.
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| 	 */
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| 	int (*write_emulated)(struct x86_emulate_ctxt *ctxt,
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| 			      unsigned long addr, const void *val,
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| 			      unsigned int bytes,
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| 			      struct x86_exception *fault);
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| 
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| 	/*
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| 	 * cmpxchg_emulated: Emulate an atomic (LOCKed) CMPXCHG operation on an
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| 	 *                   emulated/special memory area.
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| 	 *  @addr:  [IN ] Linear address to access.
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| 	 *  @old:   [IN ] Value expected to be current at @addr.
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| 	 *  @new:   [IN ] Value to write to @addr.
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| 	 *  @bytes: [IN ] Number of bytes to access using CMPXCHG.
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| 	 */
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| 	int (*cmpxchg_emulated)(struct x86_emulate_ctxt *ctxt,
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| 				unsigned long addr,
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| 				const void *old,
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| 				const void *new,
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| 				unsigned int bytes,
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| 				struct x86_exception *fault);
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| 	void (*invlpg)(struct x86_emulate_ctxt *ctxt, ulong addr);
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| 
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| 	int (*pio_in_emulated)(struct x86_emulate_ctxt *ctxt,
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| 			       int size, unsigned short port, void *val,
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| 			       unsigned int count);
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| 
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| 	int (*pio_out_emulated)(struct x86_emulate_ctxt *ctxt,
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| 				int size, unsigned short port, const void *val,
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| 				unsigned int count);
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| 
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| 	bool (*get_segment)(struct x86_emulate_ctxt *ctxt, u16 *selector,
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| 			    struct desc_struct *desc, u32 *base3, int seg);
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| 	void (*set_segment)(struct x86_emulate_ctxt *ctxt, u16 selector,
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| 			    struct desc_struct *desc, u32 base3, int seg);
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| 	unsigned long (*get_cached_segment_base)(struct x86_emulate_ctxt *ctxt,
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| 						 int seg);
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| 	void (*get_gdt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt);
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| 	void (*get_idt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt);
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| 	void (*set_gdt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt);
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| 	void (*set_idt)(struct x86_emulate_ctxt *ctxt, struct desc_ptr *dt);
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| 	ulong (*get_cr)(struct x86_emulate_ctxt *ctxt, int cr);
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| 	int (*set_cr)(struct x86_emulate_ctxt *ctxt, int cr, ulong val);
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| 	int (*cpl)(struct x86_emulate_ctxt *ctxt);
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| 	int (*get_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong *dest);
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| 	int (*set_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong value);
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| 	int (*set_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data);
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| 	int (*get_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata);
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| 	int (*check_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc);
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| 	int (*read_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc, u64 *pdata);
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| 	void (*halt)(struct x86_emulate_ctxt *ctxt);
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| 	void (*wbinvd)(struct x86_emulate_ctxt *ctxt);
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| 	int (*fix_hypercall)(struct x86_emulate_ctxt *ctxt);
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| 	void (*get_fpu)(struct x86_emulate_ctxt *ctxt); /* disables preempt */
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| 	void (*put_fpu)(struct x86_emulate_ctxt *ctxt); /* reenables preempt */
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| 	int (*intercept)(struct x86_emulate_ctxt *ctxt,
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| 			 struct x86_instruction_info *info,
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| 			 enum x86_intercept_stage stage);
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| 
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| 	void (*get_cpuid)(struct x86_emulate_ctxt *ctxt,
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| 			  u32 *eax, u32 *ebx, u32 *ecx, u32 *edx);
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| 	void (*set_nmi_mask)(struct x86_emulate_ctxt *ctxt, bool masked);
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| };
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| 
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| typedef u32 __attribute__((vector_size(16))) sse128_t;
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| 
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| /* Type, address-of, and value of an instruction's operand. */
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| struct operand {
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| 	enum { OP_REG, OP_MEM, OP_MEM_STR, OP_IMM, OP_XMM, OP_MM, OP_NONE } type;
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| 	unsigned int bytes;
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| 	unsigned int count;
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| 	union {
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| 		unsigned long orig_val;
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| 		u64 orig_val64;
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| 	};
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| 	union {
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| 		unsigned long *reg;
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| 		struct segmented_address {
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| 			ulong ea;
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| 			unsigned seg;
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| 		} mem;
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| 		unsigned xmm;
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| 		unsigned mm;
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| 	} addr;
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| 	union {
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| 		unsigned long val;
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| 		u64 val64;
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| 		char valptr[sizeof(sse128_t)];
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| 		sse128_t vec_val;
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| 		u64 mm_val;
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| 		void *data;
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| 	};
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| };
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| 
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| struct fetch_cache {
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| 	u8 data[15];
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| 	u8 *ptr;
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| 	u8 *end;
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| };
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| 
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| struct read_cache {
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| 	u8 data[1024];
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| 	unsigned long pos;
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| 	unsigned long end;
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| };
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| 
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| /* Execution mode, passed to the emulator. */
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| enum x86emul_mode {
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| 	X86EMUL_MODE_REAL,	/* Real mode.             */
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| 	X86EMUL_MODE_VM86,	/* Virtual 8086 mode.     */
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| 	X86EMUL_MODE_PROT16,	/* 16-bit protected mode. */
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| 	X86EMUL_MODE_PROT32,	/* 32-bit protected mode. */
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| 	X86EMUL_MODE_PROT64,	/* 64-bit (long) mode.    */
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| };
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| 
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| struct x86_emulate_ctxt {
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| 	const struct x86_emulate_ops *ops;
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| 
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| 	/* Register state before/after emulation. */
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| 	unsigned long eflags;
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| 	unsigned long eip; /* eip before instruction emulation */
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| 	/* Emulated execution mode, represented by an X86EMUL_MODE value. */
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| 	enum x86emul_mode mode;
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| 
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| 	/* interruptibility state, as a result of execution of STI or MOV SS */
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| 	int interruptibility;
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| 
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| 	bool guest_mode; /* guest running a nested guest */
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| 	bool perm_ok; /* do not check permissions if true */
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| 	bool ud;	/* inject an #UD if host doesn't support insn */
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| 
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| 	bool have_exception;
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| 	struct x86_exception exception;
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| 
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| 	/*
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| 	 * decode cache
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| 	 */
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| 
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| 	/* current opcode length in bytes */
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| 	u8 opcode_len;
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| 	u8 b;
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| 	u8 intercept;
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| 	u8 op_bytes;
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| 	u8 ad_bytes;
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| 	struct operand src;
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| 	struct operand src2;
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| 	struct operand dst;
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| 	int (*execute)(struct x86_emulate_ctxt *ctxt);
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| 	int (*check_perm)(struct x86_emulate_ctxt *ctxt);
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| 	/*
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| 	 * The following six fields are cleared together,
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| 	 * the rest are initialized unconditionally in x86_decode_insn
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| 	 * or elsewhere
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| 	 */
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| 	bool rip_relative;
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| 	u8 rex_prefix;
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| 	u8 lock_prefix;
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| 	u8 rep_prefix;
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| 	/* bitmaps of registers in _regs[] that can be read */
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| 	u32 regs_valid;
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| 	/* bitmaps of registers in _regs[] that have been written */
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| 	u32 regs_dirty;
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| 	/* modrm */
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| 	u8 modrm;
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| 	u8 modrm_mod;
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| 	u8 modrm_reg;
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| 	u8 modrm_rm;
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| 	u8 modrm_seg;
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| 	u8 seg_override;
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| 	u64 d;
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| 	unsigned long _eip;
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| 	struct operand memop;
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| 	/* Fields above regs are cleared together. */
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| 	unsigned long _regs[NR_VCPU_REGS];
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| 	struct operand *memopp;
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| 	struct fetch_cache fetch;
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| 	struct read_cache io_read;
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| 	struct read_cache mem_read;
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| };
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| 
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| /* Repeat String Operation Prefix */
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| #define REPE_PREFIX	0xf3
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| #define REPNE_PREFIX	0xf2
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| 
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| /* CPUID vendors */
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| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_ebx 0x68747541
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| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_ecx 0x444d4163
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| #define X86EMUL_CPUID_VENDOR_AuthenticAMD_edx 0x69746e65
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| 
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| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_ebx 0x69444d41
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| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_ecx 0x21726574
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| #define X86EMUL_CPUID_VENDOR_AMDisbetterI_edx 0x74656273
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| 
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| #define X86EMUL_CPUID_VENDOR_GenuineIntel_ebx 0x756e6547
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| #define X86EMUL_CPUID_VENDOR_GenuineIntel_ecx 0x6c65746e
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| #define X86EMUL_CPUID_VENDOR_GenuineIntel_edx 0x49656e69
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| 
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| enum x86_intercept_stage {
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| 	X86_ICTP_NONE = 0,   /* Allow zero-init to not match anything */
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| 	X86_ICPT_PRE_EXCEPT,
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| 	X86_ICPT_POST_EXCEPT,
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| 	X86_ICPT_POST_MEMACCESS,
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| };
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| 
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| enum x86_intercept {
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| 	x86_intercept_none,
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| 	x86_intercept_cr_read,
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| 	x86_intercept_cr_write,
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| 	x86_intercept_clts,
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| 	x86_intercept_lmsw,
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| 	x86_intercept_smsw,
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| 	x86_intercept_dr_read,
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| 	x86_intercept_dr_write,
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| 	x86_intercept_lidt,
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| 	x86_intercept_sidt,
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| 	x86_intercept_lgdt,
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| 	x86_intercept_sgdt,
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| 	x86_intercept_lldt,
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| 	x86_intercept_sldt,
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| 	x86_intercept_ltr,
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| 	x86_intercept_str,
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| 	x86_intercept_rdtsc,
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| 	x86_intercept_rdpmc,
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| 	x86_intercept_pushf,
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| 	x86_intercept_popf,
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| 	x86_intercept_cpuid,
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| 	x86_intercept_rsm,
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| 	x86_intercept_iret,
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| 	x86_intercept_intn,
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| 	x86_intercept_invd,
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| 	x86_intercept_pause,
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| 	x86_intercept_hlt,
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| 	x86_intercept_invlpg,
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| 	x86_intercept_invlpga,
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| 	x86_intercept_vmrun,
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| 	x86_intercept_vmload,
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| 	x86_intercept_vmsave,
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| 	x86_intercept_vmmcall,
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| 	x86_intercept_stgi,
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| 	x86_intercept_clgi,
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| 	x86_intercept_skinit,
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| 	x86_intercept_rdtscp,
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| 	x86_intercept_icebp,
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| 	x86_intercept_wbinvd,
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| 	x86_intercept_monitor,
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| 	x86_intercept_mwait,
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| 	x86_intercept_rdmsr,
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| 	x86_intercept_wrmsr,
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| 	x86_intercept_in,
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| 	x86_intercept_ins,
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| 	x86_intercept_out,
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| 	x86_intercept_outs,
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| 
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| 	nr_x86_intercepts
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| };
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| 
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| /* Host execution mode. */
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| #if defined(CONFIG_X86_32)
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| #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT32
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| #elif defined(CONFIG_X86_64)
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| #define X86EMUL_MODE_HOST X86EMUL_MODE_PROT64
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| #endif
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| 
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| int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len);
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| bool x86_page_table_writing_insn(struct x86_emulate_ctxt *ctxt);
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| #define EMULATION_FAILED -1
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| #define EMULATION_OK 0
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| #define EMULATION_RESTART 1
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| #define EMULATION_INTERCEPTED 2
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| void init_decode_cache(struct x86_emulate_ctxt *ctxt);
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| int x86_emulate_insn(struct x86_emulate_ctxt *ctxt);
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| int emulator_task_switch(struct x86_emulate_ctxt *ctxt,
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| 			 u16 tss_selector, int idt_index, int reason,
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| 			 bool has_error_code, u32 error_code);
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| int emulate_int_real(struct x86_emulate_ctxt *ctxt, int irq);
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| void emulator_invalidate_register_cache(struct x86_emulate_ctxt *ctxt);
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| void emulator_writeback_register_cache(struct x86_emulate_ctxt *ctxt);
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| 
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| #endif /* _ASM_X86_KVM_X86_EMULATE_H */
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