arch/x86/entry/entry_64_compat.S | 59 ++++++++++++++++++----------------------
 1 file changed, 26 insertions(+), 33 deletions(-)

diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index bb187a6a877c..d2fe655bd18e 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -178,34 +178,19 @@ sysexit_from_sys_call:
 
 #ifdef CONFIG_AUDITSYSCALL
 	.macro auditsys_entry_common
-	/*
-	 * At this point, registers hold syscall args in the 32-bit syscall ABI:
-	 * EAX is syscall number, the 6 args are in EBX,ECX,EDX,ESI,EDI,EBP.
-	 *
-	 * We want to pass them to __audit_syscall_entry(), which is a 64-bit
-	 * C function with 5 parameters, so shuffle them to match what
-	 * the function expects: RDI,RSI,RDX,RCX,R8.
-	 */
-	movl	%esi, %r8d		/* arg5 (R8 ) <= 4th syscall arg (ESI) */
-	xchg	%ecx, %edx		/* arg4 (RCX) <= 3rd syscall arg (EDX) */
-					/* arg3 (RDX) <= 2nd syscall arg (ECX) */
-	movl	%ebx, %esi		/* arg2 (RSI) <= 1st syscall arg (EBX) */
-	movl	%eax, %edi		/* arg1 (RDI) <= syscall number  (EAX) */
+	movl	%esi, %r8d		/* 5th arg: 4th syscall arg */
+	movl	%ecx, %r9d		/* swap with edx */
+	movl	%edx, %ecx		/* 4th arg: 3rd syscall arg */
+	movl	%r9d, %edx		/* 3rd arg: 2nd syscall arg */
+	movl	%ebx, %esi		/* 2nd arg: 1st syscall arg */
+	movl	%eax, %edi		/* 1st arg: syscall number */
 	call	__audit_syscall_entry
-
-	/*
-	 * We are going to jump back to the syscall dispatch code.
-	 * Prepare syscall args as required by the 64-bit C ABI.
-	 * Registers clobbered by __audit_syscall_entry() are
-	 * loaded from pt_regs on stack:
-	 */
-	movl	ORIG_RAX(%rsp), %eax	/* syscall number */
-	movl	%ebx, %edi		/* arg1 */
-	movl	RCX(%rsp), %esi		/* arg2 */
-	movl	RDX(%rsp), %edx		/* arg3 */
-	movl	RSI(%rsp), %ecx		/* arg4 */
-	movl	RDI(%rsp), %r8d		/* arg5 */
-	movl	%ebp, %r9d		/* arg6 */
+	movl	ORIG_RAX(%rsp), %eax	/* reload syscall number */
+	movl	%ebx, %edi		/* reload 1st syscall arg */
+	movl	RCX(%rsp), %esi		/* reload 2nd syscall arg */
+	movl	RDX(%rsp), %edx		/* reload 3rd syscall arg */
+	movl	RSI(%rsp), %ecx		/* reload 4th syscall arg */
+	movl	RDI(%rsp), %r8d		/* reload 5th syscall arg */
 	.endm
 
 	.macro auditsys_exit exit
@@ -236,6 +221,7 @@ sysexit_from_sys_call:
 
 sysenter_auditsys:
 	auditsys_entry_common
+	movl	%ebp, %r9d		/* reload 6th syscall arg */
 	jmp	sysenter_dispatch
 
 sysexit_audit:
@@ -336,7 +322,7 @@ ENTRY(entry_SYSCALL_compat)
 	 * 32-bit zero extended:
 	 */
 	ASM_STAC
-1:	movl	(%r8), %ebp
+1:	movl	(%r8), %r9d
 	_ASM_EXTABLE(1b, ia32_badarg)
 	ASM_CLAC
 	orl	$TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS)
@@ -346,7 +332,7 @@ ENTRY(entry_SYSCALL_compat)
 cstar_do_call:
 	/* 32-bit syscall -> 64-bit C ABI argument conversion */
 	movl	%edi, %r8d		/* arg5 */
-	movl	%ebp, %r9d		/* arg6 */
+	/* r9 already loaded */		/* arg6 */
 	xchg	%ecx, %esi		/* rsi:arg2, rcx:arg4 */
 	movl	%ebx, %edi		/* arg1 */
 	movl	%edx, %edx		/* arg3 (zero extension) */
@@ -358,7 +344,6 @@ cstar_dispatch:
 	call	*ia32_sys_call_table(, %rax, 8)
 	movq	%rax, RAX(%rsp)
 1:
-	movl	RCX(%rsp), %ebp
 	DISABLE_INTERRUPTS(CLBR_NONE)
 	TRACE_IRQS_OFF
 	testl	$_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
@@ -392,7 +377,9 @@ sysretl_from_sys_call:
 
 #ifdef CONFIG_AUDITSYSCALL
 cstar_auditsys:
+	movl	%r9d,R9(%rsp)		/* register to be clobbered by call */
 	auditsys_entry_common
+	movl	R9(%rsp),%r9d		/* reload 6th syscall arg */
 	jmp	cstar_dispatch
 
 sysretl_audit:
@@ -404,14 +391,16 @@ cstar_tracesys:
 	testl	$(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT), ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
 	jz	cstar_auditsys
 #endif
+	xchgl	%r9d,%ebp
 	SAVE_EXTRA_REGS
 	xorl	%eax, %eax		/* Do not leak kernel information */
 	movq	%rax, R11(%rsp)
 	movq	%rax, R10(%rsp)
-	movq	%rax, R9(%rsp)
+	movq	%r9, R9(%rsp)
 	movq	%rax, R8(%rsp)
 	movq	%rsp, %rdi		/* &pt_regs -> arg1 */
 	call	syscall_trace_enter
+	movl	R9(%rsp),%r9d
 
 	/* Reload arg registers from stack. (see sysenter_tracesys) */
 	movl	RCX(%rsp), %ecx
@@ -421,12 +410,15 @@ cstar_tracesys:
 	movl	%eax, %eax		/* zero extension */
 
 	RESTORE_EXTRA_REGS
+	xchgl	%ebp,%r9d
 	jmp	cstar_do_call
 END(entry_SYSCALL_compat)
 
 ia32_badarg:
 	ASM_CLAC
-	movq	$-EFAULT, RAX(%rsp)
+	movq	$-EFAULT, %rax
+	jmp	ia32_sysret
+
 ia32_ret_from_sys_call:
 	xorl	%eax, %eax		/* Do not leak kernel information */
 	movq	%rax, R11(%rsp)
@@ -498,6 +490,7 @@ ia32_do_call:
 	ja	1f
 
 	call	*ia32_sys_call_table(, %rax, 8)
+ia32_sysret:
 	movq	%rax, RAX(%rsp)
 1:
 	jmp	int_ret_from_sys_call