Commit dcd072e2 authored by Alexander van Heukelum's avatar Alexander van Heukelum Committed by Ingo Molnar
Browse files

x86: clean up after: move entry_64.S register saving out of the macros 



This add-on patch to x86: move entry_64.S register saving out
of the macros visually cleans up the appearance of the code by
introducing some basic helper macro's. It also adds some cfi
annotations which were missing.

Signed-off-by: default avatarAlexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent d99015b1

arch/x86/kernel/entry_64.S

+112 −108
Original line number Diff line number Diff line
@@ -60,6 +60,23 @@ 
#define __AUDIT_ARCH_LE	   0x40000000



	.code64

/*

 * Some macro's to hide the most frequently occuring CFI annotations.

 */

	.macro CFI_PUSHQ reg

	pushq \reg

	CFI_ADJUST_CFA_OFFSET 8

	.endm



	.macro CFI_POPQ reg

	popq \reg

	CFI_ADJUST_CFA_OFFSET -8

	.endm



	.macro CFI_MOVQ reg offset=0

	movq %\reg, \offset(%rsp)

	CFI_REL_OFFSET \reg, \offset

	.endm



#ifdef CONFIG_FUNCTION_TRACER

#ifdef CONFIG_DYNAMIC_FTRACE
@@ -213,84 +230,84 @@ ENTRY(native_usergs_sysret64) 
	CFI_ADJUST_CFA_OFFSET	-(6*8)

	.endm



	.macro	CFI_DEFAULT_STACK start=1

/*

 * initial frame state for interrupts (and exceptions without error code)

 */

	.macro EMPTY_FRAME start=1 offset=0

	.if \start

	CFI_STARTPROC simple

	CFI_SIGNAL_FRAME

	CFI_DEF_CFA	rsp,SS+8

	CFI_DEF_CFA rsp,8+\offset

	.else

	CFI_DEF_CFA_OFFSET SS+8

	CFI_DEF_CFA_OFFSET 8+\offset

	.endif

	CFI_REL_OFFSET	r15,R15

	CFI_REL_OFFSET	r14,R14

	CFI_REL_OFFSET	r13,R13

	CFI_REL_OFFSET	r12,R12

	CFI_REL_OFFSET	rbp,RBP

	CFI_REL_OFFSET	rbx,RBX

	CFI_REL_OFFSET	r11,R11

	CFI_REL_OFFSET	r10,R10

	CFI_REL_OFFSET	r9,R9

	CFI_REL_OFFSET	r8,R8

	CFI_REL_OFFSET	rax,RAX

	CFI_REL_OFFSET	rcx,RCX

	CFI_REL_OFFSET	rdx,RDX

	CFI_REL_OFFSET	rsi,RSI

	CFI_REL_OFFSET	rdi,RDI

	CFI_REL_OFFSET	rip,RIP

	/*CFI_REL_OFFSET	cs,CS*/

	/*CFI_REL_OFFSET	rflags,EFLAGS*/

	CFI_REL_OFFSET	rsp,RSP

	/*CFI_REL_OFFSET	ss,SS*/

	.endm



/*

 * initial frame state for interrupts and exceptions

 * initial frame state for interrupts (and exceptions without error code)

 */

	.macro _frame ref

	CFI_STARTPROC simple

	CFI_SIGNAL_FRAME

	CFI_DEF_CFA rsp,SS+8-\ref

	/*CFI_REL_OFFSET ss,SS-\ref*/

	CFI_REL_OFFSET rsp,RSP-\ref

	/*CFI_REL_OFFSET rflags,EFLAGS-\ref*/

	/*CFI_REL_OFFSET cs,CS-\ref*/

	CFI_REL_OFFSET rip,RIP-\ref

	.macro INTR_FRAME start=1 offset=0

	EMPTY_FRAME \start, (SS+8-RIP)+\offset

	/*CFI_REL_OFFSET ss, SS-RIP+\offset*/

	CFI_REL_OFFSET rsp, RSP-RIP+\offset

	/*CFI_REL_OFFSET rflags, EFLAGS-RIP+\offset*/

	/*CFI_REL_OFFSET cs, CS-RIP+\offset*/

	CFI_REL_OFFSET rip, RIP-RIP+\offset

	.endm



/*

 * initial frame state for interrupts (and exceptions without error code)

 */

#define INTR_FRAME _frame RIP

/*

 * initial frame state for exceptions with error code (and interrupts

 * with vector already pushed)

 */

#define XCPT_FRAME _frame ORIG_RAX

	.macro XCPT_FRAME start=1 offset=0

	INTR_FRAME \start, (RIP-ORIG_RAX)+\offset

	/*CFI_REL_OFFSET orig_rax, ORIG_RAX-ORIG_RAX*/

	.endm



/*

 * frame that enables calling into C.

 */

	.macro PARTIAL_FRAME start=1 offset=0

	XCPT_FRAME \start, (ORIG_RAX-ARGOFFSET)+\offset

	CFI_REL_OFFSET rdi, (RDI-ARGOFFSET)+\offset

	CFI_REL_OFFSET rsi, (RSI-ARGOFFSET)+\offset

	CFI_REL_OFFSET rdx, (RDX-ARGOFFSET)+\offset

	CFI_REL_OFFSET rcx, (RCX-ARGOFFSET)+\offset

	CFI_REL_OFFSET rax, (RAX-ARGOFFSET)+\offset

	CFI_REL_OFFSET r8, (R8-ARGOFFSET)+\offset

	CFI_REL_OFFSET r9, (R9-ARGOFFSET)+\offset

	CFI_REL_OFFSET r10, (R10-ARGOFFSET)+\offset

	CFI_REL_OFFSET r11, (R11-ARGOFFSET)+\offset

	.endm



/*

 * frame that enables passing a complete pt_regs to a C function.

 */

	.macro DEFAULT_FRAME start=1 offset=0

	PARTIAL_FRAME \start, (R11-R15)+\offset

	CFI_REL_OFFSET rbx, RBX+\offset

	CFI_REL_OFFSET rbp, RBP+\offset

	CFI_REL_OFFSET r12, R12+\offset

	CFI_REL_OFFSET r13, R13+\offset

	CFI_REL_OFFSET r14, R14+\offset

	CFI_REL_OFFSET r15, R15+\offset

	.endm



/* save partial stack frame */

ENTRY(save_args)

	XCPT_FRAME

	cld

	movq  %rdi, 8*8+16(%rsp)

	CFI_REL_OFFSET rdi, 8*8+16

	movq  %rsi, 7*8+16(%rsp)

	CFI_REL_OFFSET rsi, 7*8+16

	movq  %rdx, 6*8+16(%rsp)

	CFI_REL_OFFSET rdx, 6*8+16

	movq  %rcx, 5*8+16(%rsp)

	CFI_REL_OFFSET rcx, 5*8+16

	movq  %rax, 4*8+16(%rsp)

	CFI_REL_OFFSET rax, 4*8+16

	movq  %r8, 3*8+16(%rsp)

	CFI_REL_OFFSET r8, 3*8+16

	movq  %r9, 2*8+16(%rsp)

	CFI_REL_OFFSET r9, 2*8+16

	movq  %r10, 1*8+16(%rsp)

	CFI_REL_OFFSET r10, 1*8+16

	movq  %r11, 0*8+16(%rsp)

	CFI_REL_OFFSET r11, 0*8+16

	CFI_MOVQ rdi, (RDI-ARGOFFSET)+16

	CFI_MOVQ rsi, (RSI-ARGOFFSET)+16

	CFI_MOVQ rdx, (RDX-ARGOFFSET)+16

	CFI_MOVQ rcx, (RCX-ARGOFFSET)+16

	CFI_MOVQ rax, (RAX-ARGOFFSET)+16

	CFI_MOVQ r8, (R8-ARGOFFSET)+16

	CFI_MOVQ r9, (R9-ARGOFFSET)+16

	CFI_MOVQ r10, (R10-ARGOFFSET)+16

	CFI_MOVQ r11, (R11-ARGOFFSET)+16

	leaq -ARGOFFSET+16(%rsp),%rdi	/* arg1 for handler */

	movq %rbp, 8(%rsp)		/* push %rbp */

	CFI_MOVQ rbp, 8		/* push %rbp */

	leaq 8(%rsp), %rbp		/* mov %rsp, %ebp */

	testl $3, CS(%rdi)

	je 1f
@@ -303,9 +320,10 @@ ENTRY(save_args) 
	 */

1:	incl %gs:pda_irqcount

	jne 2f

	pop %rax			/* move return address... */

	CFI_POPQ %rax			/* move return address... */

	mov %gs:pda_irqstackptr,%rsp

	push %rax			/* ... to the new stack */

	EMPTY_FRAME 0

	CFI_PUSHQ %rax			/* ... to the new stack */

	/*

	 * We entered an interrupt context - irqs are off:

	 */
@@ -319,7 +337,7 @@ END(save_args) 
 */

/* rdi:	prev */

ENTRY(ret_from_fork)

	CFI_DEFAULT_STACK

	DEFAULT_FRAME

	push kernel_eflags(%rip)

	CFI_ADJUST_CFA_OFFSET 8

	popf				# reset kernel eflags
@@ -732,6 +750,7 @@ END(interrupt) 
	subq $10*8, %rsp

	CFI_ADJUST_CFA_OFFSET 10*8

	call save_args

	PARTIAL_FRAME 0

	call \func

	.endm
@@ -949,11 +968,11 @@ END(spurious_interrupt) 
	.macro zeroentry sym

	INTR_FRAME

	PARAVIRT_ADJUST_EXCEPTION_FRAME

	pushq $-1		/* ORIG_RAX: no syscall to restart */

	CFI_ADJUST_CFA_OFFSET 8

	CFI_PUSHQ $-1		/* ORIG_RAX: no syscall to restart */

	subq $15*8,%rsp

	CFI_ADJUST_CFA_OFFSET 15*8

	call error_entry

	DEFAULT_FRAME 0

	movq %rsp,%rdi		/* pt_regs pointer */

	xorl %esi,%esi		/* no error code */

	call \sym
@@ -967,6 +986,7 @@ END(spurious_interrupt) 
	subq $15*8,%rsp

	CFI_ADJUST_CFA_OFFSET 15*8

	call error_entry

	DEFAULT_FRAME 0

	movq %rsp,%rdi			/* pt_regs pointer */

	movq ORIG_RAX(%rsp),%rsi	/* get error code */

	movq $-1,ORIG_RAX(%rsp)		/* no syscall to restart */
@@ -1079,40 +1099,25 @@ paranoid_schedule\trace: 
 * returns in "no swapgs flag" in %ebx.

 */

KPROBE_ENTRY(error_entry)

	_frame RDI

	XCPT_FRAME

	CFI_ADJUST_CFA_OFFSET 15*8

	/* oldrax contains error code */

	cld

	movq %rdi,14*8+8(%rsp)

	CFI_REL_OFFSET rdi,RDI+8

	movq %rsi,13*8+8(%rsp)

	CFI_REL_OFFSET rsi,RSI+8

	movq %rdx,12*8+8(%rsp)

	CFI_REL_OFFSET rdx,RDX+8

	movq %rcx,11*8+8(%rsp)

	CFI_REL_OFFSET rcx,RCX+8

	movq %rax,10*8+8(%rsp)

	CFI_REL_OFFSET rax,RAX+8

	movq %r8, 9*8+8(%rsp)

	CFI_REL_OFFSET r8,R8+8

	movq %r9, 8*8+8(%rsp)

	CFI_REL_OFFSET r9,R9+8

	movq %r10,7*8+8(%rsp)

	CFI_REL_OFFSET r10,R10+8

	movq %r11,6*8+8(%rsp)

	CFI_REL_OFFSET r11,R11+8

	movq %rbx,5*8+8(%rsp)

	CFI_REL_OFFSET rbx,RBX+8

	movq %rbp,4*8+8(%rsp)

	CFI_REL_OFFSET rbp,RBP+8

	movq %r12,3*8+8(%rsp)

	CFI_REL_OFFSET r12,R12+8

	movq %r13,2*8+8(%rsp)

	CFI_REL_OFFSET r13,R13+8

	movq %r14,1*8+8(%rsp)

	CFI_REL_OFFSET r14,R14+8

	movq %r15,0*8+8(%rsp)

	CFI_REL_OFFSET r15,R15+8

	CFI_MOVQ rdi, RDI+8

	CFI_MOVQ rsi, RSI+8

	CFI_MOVQ rdx, RDX+8

	CFI_MOVQ rcx, RCX+8

	CFI_MOVQ rax, RAX+8

	CFI_MOVQ r8, R8+8

	CFI_MOVQ r9, R9+8

	CFI_MOVQ r10, R10+8

	CFI_MOVQ r11, R11+8

	CFI_MOVQ rbx, RBX+8

	CFI_MOVQ rbp, RBP+8

	CFI_MOVQ r12, R12+8

	CFI_MOVQ r13, R13+8

	CFI_MOVQ r14, R14+8

	CFI_MOVQ r15, R15+8

	xorl %ebx,%ebx

	testl $3,CS+8(%rsp)

	je error_kernelspace
@@ -1146,7 +1151,7 @@ KPROBE_END(error_entry) 


/* ebx:	no swapgs flag (1: don't need swapgs, 0: need it) */

KPROBE_ENTRY(error_exit)

	_frame R15

	DEFAULT_FRAME

	movl %ebx,%eax

	RESTORE_REST

	DISABLE_INTERRUPTS(CLBR_NONE)
@@ -1455,7 +1460,7 @@ ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs) 
   see the correct pointer to the pt_regs */

	movq %rdi, %rsp            # we don't return, adjust the stack frame

	CFI_ENDPROC

	CFI_DEFAULT_STACK

	DEFAULT_FRAME

11:	incl %gs:pda_irqcount

	movq %rsp,%rbp

	CFI_DEF_CFA_REGISTER rbp
@@ -1483,10 +1488,13 @@ END(do_hypervisor_callback) 
# with its current contents: any discrepancy means we in category 1.

*/

ENTRY(xen_failsafe_callback)

	framesz = (RIP-0x30)	/* workaround buggy gas */

	_frame framesz

	CFI_REL_OFFSET rcx, 0

	INTR_FRAME 1 (6*8)

	/*CFI_REL_OFFSET gs,GS*/

	/*CFI_REL_OFFSET fs,FS*/

	/*CFI_REL_OFFSET es,ES*/

	/*CFI_REL_OFFSET ds,DS*/

	CFI_REL_OFFSET r11,8

	CFI_REL_OFFSET rcx,0

	movw %ds,%cx

	cmpw %cx,0x10(%rsp)

	CFI_REMEMBER_STATE
@@ -1507,12 +1515,9 @@ ENTRY(xen_failsafe_callback) 
	CFI_RESTORE r11

	addq $0x30,%rsp

	CFI_ADJUST_CFA_OFFSET -0x30

	pushq $0

	CFI_ADJUST_CFA_OFFSET 8

	pushq %r11

	CFI_ADJUST_CFA_OFFSET 8

	pushq %rcx

	CFI_ADJUST_CFA_OFFSET 8

	CFI_PUSHQ $0	/* RIP */

	CFI_PUSHQ %r11

	CFI_PUSHQ %rcx

	jmp general_protection

	CFI_RESTORE_STATE

1:	/* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */
@@ -1522,8 +1527,7 @@ ENTRY(xen_failsafe_callback) 
	CFI_RESTORE r11

	addq $0x30,%rsp

	CFI_ADJUST_CFA_OFFSET -0x30

	pushq $0

	CFI_ADJUST_CFA_OFFSET 8

	CFI_PUSHQ $0

	SAVE_ALL

	jmp error_exit

	CFI_ENDPROC

CRA Git | Maintained and supported by SUSTech CRA and CCSE