 9e2d59ad58
			
		
	
	
	9e2d59ad58
	
	
	
		
			
			Pull signal handling cleanups from Al Viro:
 "This is the first pile; another one will come a bit later and will
  contain SYSCALL_DEFINE-related patches.
   - a bunch of signal-related syscalls (both native and compat)
     unified.
   - a bunch of compat syscalls switched to COMPAT_SYSCALL_DEFINE
     (fixing several potential problems with missing argument
     validation, while we are at it)
   - a lot of now-pointless wrappers killed
   - a couple of architectures (cris and hexagon) forgot to save
     altstack settings into sigframe, even though they used the
     (uninitialized) values in sigreturn; fixed.
   - microblaze fixes for delivery of multiple signals arriving at once
   - saner set of helpers for signal delivery introduced, several
     architectures switched to using those."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: (143 commits)
  x86: convert to ksignal
  sparc: convert to ksignal
  arm: switch to struct ksignal * passing
  alpha: pass k_sigaction and siginfo_t using ksignal pointer
  burying unused conditionals
  make do_sigaltstack() static
  arm64: switch to generic old sigaction() (compat-only)
  arm64: switch to generic compat rt_sigaction()
  arm64: switch compat to generic old sigsuspend
  arm64: switch to generic compat rt_sigqueueinfo()
  arm64: switch to generic compat rt_sigpending()
  arm64: switch to generic compat rt_sigprocmask()
  arm64: switch to generic sigaltstack
  sparc: switch to generic old sigsuspend
  sparc: COMPAT_SYSCALL_DEFINE does all sign-extension as well as SYSCALL_DEFINE
  sparc: kill sign-extending wrappers for native syscalls
  kill sparc32_open()
  sparc: switch to use of generic old sigaction
  sparc: switch sys_compat_rt_sigaction() to COMPAT_SYSCALL_DEFINE
  mips: switch to generic sys_fork() and sys_clone()
  ...
		
	
			
		
			
				
	
	
		
			498 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			498 lines
		
	
	
	
		
			13 KiB
			
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
 | |
|  * Compatibility mode system call entry point for x86-64. 
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|  * 		
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|  * Copyright 2000-2002 Andi Kleen, SuSE Labs.
 | |
|  */		 
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| 
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| #include <asm/dwarf2.h>
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| #include <asm/calling.h>
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| #include <asm/asm-offsets.h>
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| #include <asm/current.h>
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| #include <asm/errno.h>
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| #include <asm/ia32_unistd.h>	
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| #include <asm/thread_info.h>	
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| #include <asm/segment.h>
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| #include <asm/irqflags.h>
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| #include <asm/asm.h>
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| #include <asm/smap.h>
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| #include <linux/linkage.h>
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| #include <linux/err.h>
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| 
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| /* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this.  */
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| #include <linux/elf-em.h>
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| #define AUDIT_ARCH_I386		(EM_386|__AUDIT_ARCH_LE)
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| #define __AUDIT_ARCH_LE	   0x40000000
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| 
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| #ifndef CONFIG_AUDITSYSCALL
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| #define sysexit_audit ia32_ret_from_sys_call
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| #define sysretl_audit ia32_ret_from_sys_call
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| #endif
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| 
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| 	.section .entry.text, "ax"
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| 
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| 	.macro IA32_ARG_FIXUP noebp=0
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| 	movl	%edi,%r8d
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| 	.if \noebp
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| 	.else
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| 	movl	%ebp,%r9d
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| 	.endif
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| 	xchg	%ecx,%esi
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| 	movl	%ebx,%edi
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| 	movl	%edx,%edx	/* zero extension */
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| 	.endm 
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| 
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| 	/* clobbers %eax */	
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| 	.macro  CLEAR_RREGS offset=0, _r9=rax
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| 	xorl 	%eax,%eax
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| 	movq	%rax,\offset+R11(%rsp)
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| 	movq	%rax,\offset+R10(%rsp)
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| 	movq	%\_r9,\offset+R9(%rsp)
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| 	movq	%rax,\offset+R8(%rsp)
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| 	.endm
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| 
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| 	/*
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| 	 * Reload arg registers from stack in case ptrace changed them.
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| 	 * We don't reload %eax because syscall_trace_enter() returned
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| 	 * the %rax value we should see.  Instead, we just truncate that
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| 	 * value to 32 bits again as we did on entry from user mode.
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| 	 * If it's a new value set by user_regset during entry tracing,
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| 	 * this matches the normal truncation of the user-mode value.
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| 	 * If it's -1 to make us punt the syscall, then (u32)-1 is still
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| 	 * an appropriately invalid value.
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| 	 */
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| 	.macro LOAD_ARGS32 offset, _r9=0
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| 	.if \_r9
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| 	movl \offset+16(%rsp),%r9d
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| 	.endif
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| 	movl \offset+40(%rsp),%ecx
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| 	movl \offset+48(%rsp),%edx
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| 	movl \offset+56(%rsp),%esi
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| 	movl \offset+64(%rsp),%edi
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| 	movl %eax,%eax			/* zero extension */
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| 	.endm
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| 	
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| 	.macro CFI_STARTPROC32 simple
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| 	CFI_STARTPROC	\simple
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| 	CFI_UNDEFINED	r8
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| 	CFI_UNDEFINED	r9
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| 	CFI_UNDEFINED	r10
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| 	CFI_UNDEFINED	r11
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| 	CFI_UNDEFINED	r12
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| 	CFI_UNDEFINED	r13
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| 	CFI_UNDEFINED	r14
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| 	CFI_UNDEFINED	r15
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| 	.endm
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| 
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| #ifdef CONFIG_PARAVIRT
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| ENTRY(native_usergs_sysret32)
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| 	swapgs
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| 	sysretl
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| ENDPROC(native_usergs_sysret32)
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| 
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| ENTRY(native_irq_enable_sysexit)
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| 	swapgs
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| 	sti
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| 	sysexit
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| ENDPROC(native_irq_enable_sysexit)
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| #endif
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| 
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| /*
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|  * 32bit SYSENTER instruction entry.
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|  *
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|  * Arguments:
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|  * %eax	System call number.
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|  * %ebx Arg1
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|  * %ecx Arg2
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|  * %edx Arg3
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|  * %esi Arg4
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|  * %edi Arg5
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|  * %ebp user stack
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|  * 0(%ebp) Arg6	
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|  * 	
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|  * Interrupts off.
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|  *	
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|  * This is purely a fast path. For anything complicated we use the int 0x80
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|  * path below.	Set up a complete hardware stack frame to share code
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|  * with the int 0x80 path.
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|  */ 	
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| ENTRY(ia32_sysenter_target)
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| 	CFI_STARTPROC32	simple
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| 	CFI_SIGNAL_FRAME
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| 	CFI_DEF_CFA	rsp,0
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| 	CFI_REGISTER	rsp,rbp
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| 	SWAPGS_UNSAFE_STACK
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| 	movq	PER_CPU_VAR(kernel_stack), %rsp
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| 	addq	$(KERNEL_STACK_OFFSET),%rsp
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| 	/*
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| 	 * No need to follow this irqs on/off section: the syscall
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| 	 * disabled irqs, here we enable it straight after entry:
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| 	 */
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| 	ENABLE_INTERRUPTS(CLBR_NONE)
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|  	movl	%ebp,%ebp		/* zero extension */
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| 	pushq_cfi $__USER32_DS
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| 	/*CFI_REL_OFFSET ss,0*/
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| 	pushq_cfi %rbp
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| 	CFI_REL_OFFSET rsp,0
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| 	pushfq_cfi
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| 	/*CFI_REL_OFFSET rflags,0*/
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| 	movl	TI_sysenter_return+THREAD_INFO(%rsp,3*8-KERNEL_STACK_OFFSET),%r10d
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| 	CFI_REGISTER rip,r10
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| 	pushq_cfi $__USER32_CS
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| 	/*CFI_REL_OFFSET cs,0*/
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| 	movl	%eax, %eax
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| 	pushq_cfi %r10
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| 	CFI_REL_OFFSET rip,0
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| 	pushq_cfi %rax
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| 	cld
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| 	SAVE_ARGS 0,1,0
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|  	/* no need to do an access_ok check here because rbp has been
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|  	   32bit zero extended */ 
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| 	ASM_STAC
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| 1:	movl	(%rbp),%ebp
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| 	_ASM_EXTABLE(1b,ia32_badarg)
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| 	ASM_CLAC
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| 	orl     $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	testl   $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	CFI_REMEMBER_STATE
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| 	jnz  sysenter_tracesys
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| 	cmpq	$(IA32_NR_syscalls-1),%rax
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| 	ja	ia32_badsys
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| sysenter_do_call:
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| 	IA32_ARG_FIXUP
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| sysenter_dispatch:
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| 	call	*ia32_sys_call_table(,%rax,8)
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| 	movq	%rax,RAX-ARGOFFSET(%rsp)
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| 	DISABLE_INTERRUPTS(CLBR_NONE)
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| 	TRACE_IRQS_OFF
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| 	testl	$_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jnz	sysexit_audit
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| sysexit_from_sys_call:
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| 	andl    $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	/* clear IF, that popfq doesn't enable interrupts early */
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| 	andl  $~0x200,EFLAGS-R11(%rsp) 
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| 	movl	RIP-R11(%rsp),%edx		/* User %eip */
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| 	CFI_REGISTER rip,rdx
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| 	RESTORE_ARGS 0,24,0,0,0,0
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| 	xorq	%r8,%r8
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| 	xorq	%r9,%r9
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| 	xorq	%r10,%r10
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| 	xorq	%r11,%r11
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| 	popfq_cfi
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| 	/*CFI_RESTORE rflags*/
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| 	popq_cfi %rcx				/* User %esp */
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| 	CFI_REGISTER rsp,rcx
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| 	TRACE_IRQS_ON
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| 	ENABLE_INTERRUPTS_SYSEXIT32
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| 
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| #ifdef CONFIG_AUDITSYSCALL
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| 	.macro auditsys_entry_common
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| 	movl %esi,%r9d			/* 6th arg: 4th syscall arg */
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| 	movl %edx,%r8d			/* 5th arg: 3rd syscall arg */
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| 	/* (already in %ecx)		   4th arg: 2nd syscall arg */
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| 	movl %ebx,%edx			/* 3rd arg: 1st syscall arg */
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| 	movl %eax,%esi			/* 2nd arg: syscall number */
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| 	movl $AUDIT_ARCH_I386,%edi	/* 1st arg: audit arch */
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| 	call __audit_syscall_entry
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| 	movl RAX-ARGOFFSET(%rsp),%eax	/* reload syscall number */
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| 	cmpq $(IA32_NR_syscalls-1),%rax
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| 	ja ia32_badsys
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| 	movl %ebx,%edi			/* reload 1st syscall arg */
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| 	movl RCX-ARGOFFSET(%rsp),%esi	/* reload 2nd syscall arg */
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| 	movl RDX-ARGOFFSET(%rsp),%edx	/* reload 3rd syscall arg */
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| 	movl RSI-ARGOFFSET(%rsp),%ecx	/* reload 4th syscall arg */
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| 	movl RDI-ARGOFFSET(%rsp),%r8d	/* reload 5th syscall arg */
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| 	.endm
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| 
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| 	.macro auditsys_exit exit
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| 	testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jnz ia32_ret_from_sys_call
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| 	TRACE_IRQS_ON
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| 	ENABLE_INTERRUPTS(CLBR_NONE)
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| 	movl %eax,%esi		/* second arg, syscall return value */
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| 	cmpl $-MAX_ERRNO,%eax	/* is it an error ? */
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| 	jbe 1f
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| 	movslq %eax, %rsi	/* if error sign extend to 64 bits */
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| 1:	setbe %al		/* 1 if error, 0 if not */
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| 	movzbl %al,%edi		/* zero-extend that into %edi */
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| 	call __audit_syscall_exit
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| 	movq RAX-ARGOFFSET(%rsp),%rax	/* reload syscall return value */
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| 	movl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT),%edi
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| 	DISABLE_INTERRUPTS(CLBR_NONE)
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| 	TRACE_IRQS_OFF
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| 	testl %edi,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jz \exit
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| 	CLEAR_RREGS -ARGOFFSET
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| 	jmp int_with_check
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| 	.endm
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| 
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| sysenter_auditsys:
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| 	CFI_RESTORE_STATE
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| 	auditsys_entry_common
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| 	movl %ebp,%r9d			/* reload 6th syscall arg */
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| 	jmp sysenter_dispatch
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| 
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| sysexit_audit:
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| 	auditsys_exit sysexit_from_sys_call
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| #endif
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| 
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| sysenter_tracesys:
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| #ifdef CONFIG_AUDITSYSCALL
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| 	testl	$(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jz	sysenter_auditsys
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| #endif
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| 	SAVE_REST
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| 	CLEAR_RREGS
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| 	movq	$-ENOSYS,RAX(%rsp)/* ptrace can change this for a bad syscall */
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| 	movq	%rsp,%rdi        /* &pt_regs -> arg1 */
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| 	call	syscall_trace_enter
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| 	LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
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| 	RESTORE_REST
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| 	cmpq	$(IA32_NR_syscalls-1),%rax
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| 	ja	int_ret_from_sys_call /* sysenter_tracesys has set RAX(%rsp) */
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| 	jmp	sysenter_do_call
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| 	CFI_ENDPROC
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| ENDPROC(ia32_sysenter_target)
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| 
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| /*
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|  * 32bit SYSCALL instruction entry.
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|  *
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|  * Arguments:
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|  * %eax	System call number.
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|  * %ebx Arg1
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|  * %ecx return EIP 
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|  * %edx Arg3
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|  * %esi Arg4
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|  * %edi Arg5
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|  * %ebp Arg2    [note: not saved in the stack frame, should not be touched]
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|  * %esp user stack 
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|  * 0(%esp) Arg6
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|  * 	
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|  * Interrupts off.
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|  *	
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|  * This is purely a fast path. For anything complicated we use the int 0x80
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|  * path below.	Set up a complete hardware stack frame to share code
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|  * with the int 0x80 path.	
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|  */ 	
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| ENTRY(ia32_cstar_target)
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| 	CFI_STARTPROC32	simple
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| 	CFI_SIGNAL_FRAME
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| 	CFI_DEF_CFA	rsp,KERNEL_STACK_OFFSET
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| 	CFI_REGISTER	rip,rcx
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| 	/*CFI_REGISTER	rflags,r11*/
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| 	SWAPGS_UNSAFE_STACK
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| 	movl	%esp,%r8d
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| 	CFI_REGISTER	rsp,r8
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| 	movq	PER_CPU_VAR(kernel_stack),%rsp
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| 	/*
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| 	 * No need to follow this irqs on/off section: the syscall
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| 	 * disabled irqs and here we enable it straight after entry:
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| 	 */
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| 	ENABLE_INTERRUPTS(CLBR_NONE)
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| 	SAVE_ARGS 8,0,0
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| 	movl 	%eax,%eax	/* zero extension */
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| 	movq	%rax,ORIG_RAX-ARGOFFSET(%rsp)
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| 	movq	%rcx,RIP-ARGOFFSET(%rsp)
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| 	CFI_REL_OFFSET rip,RIP-ARGOFFSET
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| 	movq	%rbp,RCX-ARGOFFSET(%rsp) /* this lies slightly to ptrace */
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| 	movl	%ebp,%ecx
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| 	movq	$__USER32_CS,CS-ARGOFFSET(%rsp)
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| 	movq	$__USER32_DS,SS-ARGOFFSET(%rsp)
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| 	movq	%r11,EFLAGS-ARGOFFSET(%rsp)
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| 	/*CFI_REL_OFFSET rflags,EFLAGS-ARGOFFSET*/
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| 	movq	%r8,RSP-ARGOFFSET(%rsp)	
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| 	CFI_REL_OFFSET rsp,RSP-ARGOFFSET
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| 	/* no need to do an access_ok check here because r8 has been
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| 	   32bit zero extended */ 
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| 	/* hardware stack frame is complete now */	
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| 	ASM_STAC
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| 1:	movl	(%r8),%r9d
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| 	_ASM_EXTABLE(1b,ia32_badarg)
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| 	ASM_CLAC
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| 	orl     $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	testl   $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	CFI_REMEMBER_STATE
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| 	jnz   cstar_tracesys
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| 	cmpq $IA32_NR_syscalls-1,%rax
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| 	ja  ia32_badsys
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| cstar_do_call:
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| 	IA32_ARG_FIXUP 1
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| cstar_dispatch:
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| 	call *ia32_sys_call_table(,%rax,8)
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| 	movq %rax,RAX-ARGOFFSET(%rsp)
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| 	DISABLE_INTERRUPTS(CLBR_NONE)
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| 	TRACE_IRQS_OFF
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| 	testl $_TIF_ALLWORK_MASK,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jnz sysretl_audit
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| sysretl_from_sys_call:
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| 	andl $~TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	RESTORE_ARGS 0,-ARG_SKIP,0,0,0
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| 	movl RIP-ARGOFFSET(%rsp),%ecx
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| 	CFI_REGISTER rip,rcx
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| 	movl EFLAGS-ARGOFFSET(%rsp),%r11d	
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| 	/*CFI_REGISTER rflags,r11*/
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| 	xorq	%r10,%r10
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| 	xorq	%r9,%r9
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| 	xorq	%r8,%r8
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| 	TRACE_IRQS_ON
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| 	movl RSP-ARGOFFSET(%rsp),%esp
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| 	CFI_RESTORE rsp
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| 	USERGS_SYSRET32
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| 	
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| #ifdef CONFIG_AUDITSYSCALL
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| cstar_auditsys:
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| 	CFI_RESTORE_STATE
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| 	movl %r9d,R9-ARGOFFSET(%rsp)	/* register to be clobbered by call */
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| 	auditsys_entry_common
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| 	movl R9-ARGOFFSET(%rsp),%r9d	/* reload 6th syscall arg */
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| 	jmp cstar_dispatch
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| 
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| sysretl_audit:
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| 	auditsys_exit sysretl_from_sys_call
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| #endif
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| 
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| cstar_tracesys:
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| #ifdef CONFIG_AUDITSYSCALL
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| 	testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
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| 	jz cstar_auditsys
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| #endif
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| 	xchgl %r9d,%ebp
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| 	SAVE_REST
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| 	CLEAR_RREGS 0, r9
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| 	movq $-ENOSYS,RAX(%rsp)	/* ptrace can change this for a bad syscall */
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| 	movq %rsp,%rdi        /* &pt_regs -> arg1 */
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| 	call syscall_trace_enter
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| 	LOAD_ARGS32 ARGOFFSET, 1  /* reload args from stack in case ptrace changed it */
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| 	RESTORE_REST
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| 	xchgl %ebp,%r9d
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| 	cmpq $(IA32_NR_syscalls-1),%rax
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| 	ja int_ret_from_sys_call /* cstar_tracesys has set RAX(%rsp) */
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| 	jmp cstar_do_call
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| END(ia32_cstar_target)
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| 				
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| ia32_badarg:
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| 	ASM_CLAC
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| 	movq $-EFAULT,%rax
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| 	jmp ia32_sysret
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| 	CFI_ENDPROC
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| 
 | |
| /* 
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|  * Emulated IA32 system calls via int 0x80. 
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|  *
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|  * Arguments:	 
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|  * %eax	System call number.
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|  * %ebx Arg1
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|  * %ecx Arg2
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|  * %edx Arg3
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|  * %esi Arg4
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|  * %edi Arg5
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|  * %ebp Arg6    [note: not saved in the stack frame, should not be touched]
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|  *
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|  * Notes:
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|  * Uses the same stack frame as the x86-64 version.	
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|  * All registers except %eax must be saved (but ptrace may violate that)
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|  * Arguments are zero extended. For system calls that want sign extension and
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|  * take long arguments a wrapper is needed. Most calls can just be called
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|  * directly.
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|  * Assumes it is only called from user space and entered with interrupts off.	
 | |
|  */ 				
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| 
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| ENTRY(ia32_syscall)
 | |
| 	CFI_STARTPROC32	simple
 | |
| 	CFI_SIGNAL_FRAME
 | |
| 	CFI_DEF_CFA	rsp,SS+8-RIP
 | |
| 	/*CFI_REL_OFFSET	ss,SS-RIP*/
 | |
| 	CFI_REL_OFFSET	rsp,RSP-RIP
 | |
| 	/*CFI_REL_OFFSET	rflags,EFLAGS-RIP*/
 | |
| 	/*CFI_REL_OFFSET	cs,CS-RIP*/
 | |
| 	CFI_REL_OFFSET	rip,RIP-RIP
 | |
| 	PARAVIRT_ADJUST_EXCEPTION_FRAME
 | |
| 	SWAPGS
 | |
| 	/*
 | |
| 	 * No need to follow this irqs on/off section: the syscall
 | |
| 	 * disabled irqs and here we enable it straight after entry:
 | |
| 	 */
 | |
| 	ENABLE_INTERRUPTS(CLBR_NONE)
 | |
| 	movl %eax,%eax
 | |
| 	pushq_cfi %rax
 | |
| 	cld
 | |
| 	/* note the registers are not zero extended to the sf.
 | |
| 	   this could be a problem. */
 | |
| 	SAVE_ARGS 0,1,0
 | |
| 	orl $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)
 | |
| 	testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)
 | |
| 	jnz ia32_tracesys
 | |
| 	cmpq $(IA32_NR_syscalls-1),%rax
 | |
| 	ja ia32_badsys
 | |
| ia32_do_call:
 | |
| 	IA32_ARG_FIXUP
 | |
| 	call *ia32_sys_call_table(,%rax,8) # xxx: rip relative
 | |
| ia32_sysret:
 | |
| 	movq %rax,RAX-ARGOFFSET(%rsp)
 | |
| ia32_ret_from_sys_call:
 | |
| 	CLEAR_RREGS -ARGOFFSET
 | |
| 	jmp int_ret_from_sys_call 
 | |
| 
 | |
| ia32_tracesys:			 
 | |
| 	SAVE_REST
 | |
| 	CLEAR_RREGS
 | |
| 	movq $-ENOSYS,RAX(%rsp)	/* ptrace can change this for a bad syscall */
 | |
| 	movq %rsp,%rdi        /* &pt_regs -> arg1 */
 | |
| 	call syscall_trace_enter
 | |
| 	LOAD_ARGS32 ARGOFFSET  /* reload args from stack in case ptrace changed it */
 | |
| 	RESTORE_REST
 | |
| 	cmpq $(IA32_NR_syscalls-1),%rax
 | |
| 	ja  int_ret_from_sys_call	/* ia32_tracesys has set RAX(%rsp) */
 | |
| 	jmp ia32_do_call
 | |
| END(ia32_syscall)
 | |
| 
 | |
| ia32_badsys:
 | |
| 	movq $0,ORIG_RAX-ARGOFFSET(%rsp)
 | |
| 	movq $-ENOSYS,%rax
 | |
| 	jmp ia32_sysret
 | |
| 
 | |
| 	CFI_ENDPROC
 | |
| 	
 | |
| 	.macro PTREGSCALL label, func, arg
 | |
| 	ALIGN
 | |
| GLOBAL(\label)
 | |
| 	leaq \func(%rip),%rax
 | |
| 	jmp  ia32_ptregs_common	
 | |
| 	.endm
 | |
| 
 | |
| 	CFI_STARTPROC32
 | |
| 
 | |
| 	PTREGSCALL stub32_rt_sigreturn, sys32_rt_sigreturn
 | |
| 	PTREGSCALL stub32_sigreturn, sys32_sigreturn
 | |
| 	PTREGSCALL stub32_execve, compat_sys_execve
 | |
| 	PTREGSCALL stub32_fork, sys_fork
 | |
| 	PTREGSCALL stub32_vfork, sys_vfork
 | |
| 
 | |
| 	ALIGN
 | |
| GLOBAL(stub32_clone)
 | |
| 	leaq sys_clone(%rip),%rax
 | |
| 	mov	%r8, %rcx
 | |
| 	jmp  ia32_ptregs_common	
 | |
| 
 | |
| 	ALIGN
 | |
| ia32_ptregs_common:
 | |
| 	popq %r11
 | |
| 	CFI_ENDPROC
 | |
| 	CFI_STARTPROC32	simple
 | |
| 	CFI_SIGNAL_FRAME
 | |
| 	CFI_DEF_CFA	rsp,SS+8-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rax,RAX-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rcx,RCX-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rdx,RDX-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rsi,RSI-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rdi,RDI-ARGOFFSET
 | |
| 	CFI_REL_OFFSET	rip,RIP-ARGOFFSET
 | |
| /*	CFI_REL_OFFSET	cs,CS-ARGOFFSET*/
 | |
| /*	CFI_REL_OFFSET	rflags,EFLAGS-ARGOFFSET*/
 | |
| 	CFI_REL_OFFSET	rsp,RSP-ARGOFFSET
 | |
| /*	CFI_REL_OFFSET	ss,SS-ARGOFFSET*/
 | |
| 	SAVE_REST
 | |
| 	call *%rax
 | |
| 	RESTORE_REST
 | |
| 	jmp  ia32_sysret	/* misbalances the return cache */
 | |
| 	CFI_ENDPROC
 | |
| END(ia32_ptregs_common)
 |