[PATCH] x86/asm/entry/64: Clean up entry_64.S

From: Ingo Molnar
Date: Mon Jun 08 2015 - 14:43:07 EST


Make the 64-bit syscall entry code a bit more readable:

- use consistent assembly coding style similar to the other entry_*.S files

- remove old comments that are not true anymore

- eliminate whitespace noise

- use consistent vertical spacing

- fix various comments

- reorganize entry point generation tables to be more readable

No code changed:

# arch/x86/entry/entry_64.o:

text data bss dec hex filename
12282 0 0 12282 2ffa entry_64.o.before
12282 0 0 12282 2ffa entry_64.o.after

md5:
cbab1f2d727a2a8a87618eeb79f391b7 entry_64.o.before.asm
cbab1f2d727a2a8a87618eeb79f391b7 entry_64.o.after.asm

Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/entry/entry_64.S | 820 +++++++++++++++++++++++-----------------------
1 file changed, 404 insertions(+), 416 deletions(-)

diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index d2a0ed211bed..bd97161f90cb 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -4,26 +4,20 @@
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
* Copyright (C) 2000 Pavel Machek <pavel@xxxxxxx>
- */
-
-/*
+ *
* entry.S contains the system-call and fault low-level handling routines.
*
* Some of this is documented in Documentation/x86/entry_64.txt
*
- * NOTE: This code handles signal-recognition, which happens every time
- * after an interrupt and after each system call.
- *
* A note on terminology:
- * - iret frame: Architecture defined interrupt frame from SS to RIP
- * at the top of the kernel process stack.
+ * - iret frame: Architecture defined interrupt frame from SS to RIP
+ * at the top of the kernel process stack.
*
* Some macro usage:
- * - ENTRY/END Define functions in the symbol table.
- * - TRACE_IRQ_* - Trace hard interrupt state for lock debugging.
- * - idtentry - Define exception entry points.
+ * - ENTRY/END: Define functions in the symbol table.
+ * - TRACE_IRQ_*: Trace hardirq state for lock debugging.
+ * - idtentry: Define exception entry points.
*/
-
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/cache.h>
@@ -46,13 +40,12 @@

/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
#include <linux/elf-em.h>
-#define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
-#define __AUDIT_ARCH_64BIT 0x80000000
-#define __AUDIT_ARCH_LE 0x40000000
-
- .code64
- .section .entry.text, "ax"
+#define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
+#define __AUDIT_ARCH_64BIT 0x80000000
+#define __AUDIT_ARCH_LE 0x40000000

+.code64
+.section .entry.text, "ax"

#ifdef CONFIG_PARAVIRT
ENTRY(native_usergs_sysret64)
@@ -61,11 +54,10 @@ ENTRY(native_usergs_sysret64)
ENDPROC(native_usergs_sysret64)
#endif /* CONFIG_PARAVIRT */

-
.macro TRACE_IRQS_IRETQ
#ifdef CONFIG_TRACE_IRQFLAGS
- bt $9,EFLAGS(%rsp) /* interrupts off? */
- jnc 1f
+ bt $9, EFLAGS(%rsp) /* interrupts off? */
+ jnc 1f
TRACE_IRQS_ON
1:
#endif
@@ -85,34 +77,34 @@ ENDPROC(native_usergs_sysret64)
#if defined(CONFIG_DYNAMIC_FTRACE) && defined(CONFIG_TRACE_IRQFLAGS)

.macro TRACE_IRQS_OFF_DEBUG
- call debug_stack_set_zero
+ call debug_stack_set_zero
TRACE_IRQS_OFF
- call debug_stack_reset
+ call debug_stack_reset
.endm

.macro TRACE_IRQS_ON_DEBUG
- call debug_stack_set_zero
+ call debug_stack_set_zero
TRACE_IRQS_ON
- call debug_stack_reset
+ call debug_stack_reset
.endm

.macro TRACE_IRQS_IRETQ_DEBUG
- bt $9,EFLAGS(%rsp) /* interrupts off? */
- jnc 1f
+ bt $9, EFLAGS(%rsp) /* interrupts off? */
+ jnc 1f
TRACE_IRQS_ON_DEBUG
1:
.endm

#else
-# define TRACE_IRQS_OFF_DEBUG TRACE_IRQS_OFF
-# define TRACE_IRQS_ON_DEBUG TRACE_IRQS_ON
-# define TRACE_IRQS_IRETQ_DEBUG TRACE_IRQS_IRETQ
+# define TRACE_IRQS_OFF_DEBUG TRACE_IRQS_OFF
+# define TRACE_IRQS_ON_DEBUG TRACE_IRQS_ON
+# define TRACE_IRQS_IRETQ_DEBUG TRACE_IRQS_IRETQ
#endif

/*
- * 64bit SYSCALL instruction entry. Up to 6 arguments in registers.
+ * 64-bit SYSCALL instruction entry. Up to 6 arguments in registers.
*
- * 64bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11,
+ * 64-bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11,
* then loads new ss, cs, and rip from previously programmed MSRs.
* rflags gets masked by a value from another MSR (so CLD and CLAC
* are not needed). SYSCALL does not save anything on the stack
@@ -128,7 +120,7 @@ ENDPROC(native_usergs_sysret64)
* r10 arg3 (needs to be moved to rcx to conform to C ABI)
* r8 arg4
* r9 arg5
- * (note: r12-r15,rbp,rbx are callee-preserved in C ABI)
+ * (note: r12-r15, rbp, rbx are callee-preserved in C ABI)
*
* Only called from user space.
*
@@ -151,12 +143,12 @@ ENTRY(entry_SYSCALL_64)
*/
GLOBAL(entry_SYSCALL_64_after_swapgs)

- movq %rsp,PER_CPU_VAR(rsp_scratch)
- movq PER_CPU_VAR(cpu_current_top_of_stack),%rsp
+ movq %rsp, PER_CPU_VAR(rsp_scratch)
+ movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp

/* Construct struct pt_regs on stack */
- pushq $__USER_DS /* pt_regs->ss */
- pushq PER_CPU_VAR(rsp_scratch) /* pt_regs->sp */
+ pushq $__USER_DS /* pt_regs->ss */
+ pushq PER_CPU_VAR(rsp_scratch) /* pt_regs->sp */
/*
* Re-enable interrupts.
* We use 'rsp_scratch' as a scratch space, hence irq-off block above
@@ -165,34 +157,34 @@ GLOBAL(entry_SYSCALL_64_after_swapgs)
* with using rsp_scratch:
*/
ENABLE_INTERRUPTS(CLBR_NONE)
- pushq %r11 /* pt_regs->flags */
- pushq $__USER_CS /* pt_regs->cs */
- pushq %rcx /* pt_regs->ip */
- pushq %rax /* pt_regs->orig_ax */
- pushq %rdi /* pt_regs->di */
- pushq %rsi /* pt_regs->si */
- pushq %rdx /* pt_regs->dx */
- pushq %rcx /* pt_regs->cx */
- pushq $-ENOSYS /* pt_regs->ax */
- pushq %r8 /* pt_regs->r8 */
- pushq %r9 /* pt_regs->r9 */
- pushq %r10 /* pt_regs->r10 */
- pushq %r11 /* pt_regs->r11 */
- sub $(6*8),%rsp /* pt_regs->bp,bx,r12-15 not saved */
-
- testl $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
- jnz tracesys
+ pushq %r11 /* pt_regs->flags */
+ pushq $__USER_CS /* pt_regs->cs */
+ pushq %rcx /* pt_regs->ip */
+ pushq %rax /* pt_regs->orig_ax */
+ pushq %rdi /* pt_regs->di */
+ pushq %rsi /* pt_regs->si */
+ pushq %rdx /* pt_regs->dx */
+ pushq %rcx /* pt_regs->cx */
+ pushq $-ENOSYS /* pt_regs->ax */
+ pushq %r8 /* pt_regs->r8 */
+ pushq %r9 /* pt_regs->r9 */
+ pushq %r10 /* pt_regs->r10 */
+ pushq %r11 /* pt_regs->r11 */
+ sub $(6*8), %rsp /* pt_regs->bp, bx, r12-15 not saved */
+
+ testl $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
+ jnz tracesys
entry_SYSCALL_64_fastpath:
#if __SYSCALL_MASK == ~0
- cmpq $__NR_syscall_max,%rax
+ cmpq $__NR_syscall_max, %rax
#else
- andl $__SYSCALL_MASK,%eax
- cmpl $__NR_syscall_max,%eax
+ andl $__SYSCALL_MASK, %eax
+ cmpl $__NR_syscall_max, %eax
#endif
- ja 1f /* return -ENOSYS (already in pt_regs->ax) */
- movq %r10,%rcx
- call *sys_call_table(,%rax,8)
- movq %rax,RAX(%rsp)
+ ja 1f /* return -ENOSYS (already in pt_regs->ax) */
+ movq %r10, %rcx
+ call *sys_call_table(, %rax, 8)
+ movq %rax, RAX(%rsp)
1:
/*
* Syscall return path ending with SYSRET (fast path).
@@ -213,15 +205,15 @@ GLOBAL(entry_SYSCALL_64_after_swapgs)
* flags (TIF_NOTIFY_RESUME, TIF_USER_RETURN_NOTIFY, etc) set is
* very bad.
*/
- testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
- jnz int_ret_from_sys_call_irqs_off /* Go to the slow path */
+ testl $_TIF_ALLWORK_MASK, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS)
+ jnz int_ret_from_sys_call_irqs_off /* Go to the slow path */

RESTORE_C_REGS_EXCEPT_RCX_R11
- movq RIP(%rsp),%rcx
- movq EFLAGS(%rsp),%r11
- movq RSP(%rsp),%rsp
+ movq RIP(%rsp), %rcx
+ movq EFLAGS(%rsp), %r11
+ movq RSP(%rsp), %rsp
/*
- * 64bit SYSRET restores rip from rcx,
+ * 64-bit SYSRET restores rip from rcx,
* rflags from r11 (but RF and VM bits are forced to 0),
* cs and ss are loaded from MSRs.
* Restoration of rflags re-enables interrupts.
@@ -239,21 +231,21 @@ GLOBAL(entry_SYSCALL_64_after_swapgs)

/* Do syscall entry tracing */
tracesys:
- movq %rsp, %rdi
- movl $AUDIT_ARCH_X86_64, %esi
- call syscall_trace_enter_phase1
- test %rax, %rax
- jnz tracesys_phase2 /* if needed, run the slow path */
- RESTORE_C_REGS_EXCEPT_RAX /* else restore clobbered regs */
- movq ORIG_RAX(%rsp), %rax
- jmp entry_SYSCALL_64_fastpath /* and return to the fast path */
+ movq %rsp, %rdi
+ movl $AUDIT_ARCH_X86_64, %esi
+ call syscall_trace_enter_phase1
+ test %rax, %rax
+ jnz tracesys_phase2 /* if needed, run the slow path */
+ RESTORE_C_REGS_EXCEPT_RAX /* else restore clobbered regs */
+ movq ORIG_RAX(%rsp), %rax
+ jmp entry_SYSCALL_64_fastpath /* and return to the fast path */

tracesys_phase2:
SAVE_EXTRA_REGS
- movq %rsp, %rdi
- movl $AUDIT_ARCH_X86_64, %esi
- movq %rax,%rdx
- call syscall_trace_enter_phase2
+ movq %rsp, %rdi
+ movl $AUDIT_ARCH_X86_64, %esi
+ movq %rax, %rdx
+ call syscall_trace_enter_phase2

/*
* Reload registers from stack in case ptrace changed them.
@@ -263,15 +255,15 @@ GLOBAL(entry_SYSCALL_64_after_swapgs)
RESTORE_C_REGS_EXCEPT_RAX
RESTORE_EXTRA_REGS
#if __SYSCALL_MASK == ~0
- cmpq $__NR_syscall_max,%rax
+ cmpq $__NR_syscall_max, %rax
#else
- andl $__SYSCALL_MASK,%eax
- cmpl $__NR_syscall_max,%eax
+ andl $__SYSCALL_MASK, %eax
+ cmpl $__NR_syscall_max, %eax
#endif
- ja 1f /* return -ENOSYS (already in pt_regs->ax) */
- movq %r10,%rcx /* fixup for C */
- call *sys_call_table(,%rax,8)
- movq %rax,RAX(%rsp)
+ ja 1f /* return -ENOSYS (already in pt_regs->ax) */
+ movq %r10, %rcx /* fixup for C */
+ call *sys_call_table(, %rax, 8)
+ movq %rax, RAX(%rsp)
1:
/* Use IRET because user could have changed pt_regs->foo */

@@ -283,31 +275,33 @@ GLOBAL(int_ret_from_sys_call)
DISABLE_INTERRUPTS(CLBR_NONE)
int_ret_from_sys_call_irqs_off: /* jumps come here from the irqs-off SYSRET path */
TRACE_IRQS_OFF
- movl $_TIF_ALLWORK_MASK,%edi
+ movl $_TIF_ALLWORK_MASK, %edi
/* edi: mask to check */
GLOBAL(int_with_check)
LOCKDEP_SYS_EXIT_IRQ
GET_THREAD_INFO(%rcx)
- movl TI_flags(%rcx),%edx
- andl %edi,%edx
- jnz int_careful
- andl $~TS_COMPAT,TI_status(%rcx)
+ movl TI_flags(%rcx), %edx
+ andl %edi, %edx
+ jnz int_careful
+ andl $~TS_COMPAT, TI_status(%rcx)
jmp syscall_return

- /* Either reschedule or signal or syscall exit tracking needed. */
- /* First do a reschedule test. */
- /* edx: work, edi: workmask */
+ /*
+ * Either reschedule or signal or syscall exit tracking needed.
+ * First do a reschedule test.
+ * edx: work, edi: workmask
+ */
int_careful:
- bt $TIF_NEED_RESCHED,%edx
- jnc int_very_careful
+ bt $TIF_NEED_RESCHED, %edx
+ jnc int_very_careful
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
- pushq %rdi
+ pushq %rdi
SCHEDULE_USER
- popq %rdi
+ popq %rdi
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- jmp int_with_check
+ jmp int_with_check

/* handle signals and tracing -- both require a full pt_regs */
int_very_careful:
@@ -315,27 +309,27 @@ GLOBAL(int_with_check)
ENABLE_INTERRUPTS(CLBR_NONE)
SAVE_EXTRA_REGS
/* Check for syscall exit trace */
- testl $_TIF_WORK_SYSCALL_EXIT,%edx
- jz int_signal
- pushq %rdi
- leaq 8(%rsp),%rdi # &ptregs -> arg1
- call syscall_trace_leave
- popq %rdi
- andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU),%edi
- jmp int_restore_rest
+ testl $_TIF_WORK_SYSCALL_EXIT, %edx
+ jz int_signal
+ pushq %rdi
+ leaq 8(%rsp), %rdi /* &ptregs -> arg1 */
+ call syscall_trace_leave
+ popq %rdi
+ andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU), %edi
+ jmp int_restore_rest

int_signal:
- testl $_TIF_DO_NOTIFY_MASK,%edx
- jz 1f
- movq %rsp,%rdi # &ptregs -> arg1
- xorl %esi,%esi # oldset -> arg2
- call do_notify_resume
-1: movl $_TIF_WORK_MASK,%edi
+ testl $_TIF_DO_NOTIFY_MASK, %edx
+ jz 1f
+ movq %rsp, %rdi /* &ptregs -> arg1 */
+ xorl %esi, %esi /* oldset -> arg2 */
+ call do_notify_resume
+1: movl $_TIF_WORK_MASK, %edi
int_restore_rest:
RESTORE_EXTRA_REGS
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- jmp int_with_check
+ jmp int_with_check

syscall_return:
/* The IRETQ could re-enable interrupts: */
@@ -346,10 +340,10 @@ GLOBAL(int_with_check)
* Try to use SYSRET instead of IRET if we're returning to
* a completely clean 64-bit userspace context.
*/
- movq RCX(%rsp),%rcx
- movq RIP(%rsp),%r11
- cmpq %rcx,%r11 /* RCX == RIP */
- jne opportunistic_sysret_failed
+ movq RCX(%rsp), %rcx
+ movq RIP(%rsp), %r11
+ cmpq %rcx, %r11 /* RCX == RIP */
+ jne opportunistic_sysret_failed

/*
* On Intel CPUs, SYSRET with non-canonical RCX/RIP will #GP
@@ -362,19 +356,21 @@ GLOBAL(int_with_check)
.ifne __VIRTUAL_MASK_SHIFT - 47
.error "virtual address width changed -- SYSRET checks need update"
.endif
+
/* Change top 16 bits to be the sign-extension of 47th bit */
shl $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
sar $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
+
/* If this changed %rcx, it was not canonical */
cmpq %rcx, %r11
jne opportunistic_sysret_failed

- cmpq $__USER_CS,CS(%rsp) /* CS must match SYSRET */
- jne opportunistic_sysret_failed
+ cmpq $__USER_CS, CS(%rsp) /* CS must match SYSRET */
+ jne opportunistic_sysret_failed

- movq R11(%rsp),%r11
- cmpq %r11,EFLAGS(%rsp) /* R11 == RFLAGS */
- jne opportunistic_sysret_failed
+ movq R11(%rsp), %r11
+ cmpq %r11, EFLAGS(%rsp) /* R11 == RFLAGS */
+ jne opportunistic_sysret_failed

/*
* SYSRET can't restore RF. SYSRET can restore TF, but unlike IRET,
@@ -383,29 +379,29 @@ GLOBAL(int_with_check)
* with register state that satisfies the opportunistic SYSRET
* conditions. For example, single-stepping this user code:
*
- * movq $stuck_here,%rcx
+ * movq $stuck_here, %rcx
* pushfq
* popq %r11
* stuck_here:
*
* would never get past 'stuck_here'.
*/
- testq $(X86_EFLAGS_RF|X86_EFLAGS_TF), %r11
- jnz opportunistic_sysret_failed
+ testq $(X86_EFLAGS_RF|X86_EFLAGS_TF), %r11
+ jnz opportunistic_sysret_failed

/* nothing to check for RSP */

- cmpq $__USER_DS,SS(%rsp) /* SS must match SYSRET */
- jne opportunistic_sysret_failed
+ cmpq $__USER_DS, SS(%rsp) /* SS must match SYSRET */
+ jne opportunistic_sysret_failed

/*
- * We win! This label is here just for ease of understanding
- * perf profiles. Nothing jumps here.
+ * We win! This label is here just for ease of understanding
+ * perf profiles. Nothing jumps here.
*/
syscall_return_via_sysret:
/* rcx and r11 are already restored (see code above) */
RESTORE_C_REGS_EXCEPT_RCX_R11
- movq RSP(%rsp),%rsp
+ movq RSP(%rsp), %rsp
USERGS_SYSRET64

opportunistic_sysret_failed:
@@ -417,7 +413,7 @@ END(entry_SYSCALL_64)
.macro FORK_LIKE func
ENTRY(stub_\func)
SAVE_EXTRA_REGS 8
- jmp sys_\func
+ jmp sys_\func
END(stub_\func)
.endm

@@ -436,7 +432,7 @@ ENTRY(stub_execve)
/* must use IRET code path (pt_regs->cs may have changed) */
addq $8, %rsp
ZERO_EXTRA_REGS
- movq %rax,RAX(%rsp)
+ movq %rax, RAX(%rsp)
jmp int_ret_from_sys_call
END(stub_execve)
/*
@@ -479,19 +475,19 @@ ENTRY(stub_rt_sigreturn)
* we SAVE_EXTRA_REGS here.
*/
SAVE_EXTRA_REGS 8
- call sys_rt_sigreturn
+ call sys_rt_sigreturn
return_from_stub:
addq $8, %rsp
RESTORE_EXTRA_REGS
- movq %rax,RAX(%rsp)
- jmp int_ret_from_sys_call
+ movq %rax, RAX(%rsp)
+ jmp int_ret_from_sys_call
END(stub_rt_sigreturn)

#ifdef CONFIG_X86_X32_ABI
ENTRY(stub_x32_rt_sigreturn)
SAVE_EXTRA_REGS 8
- call sys32_x32_rt_sigreturn
- jmp return_from_stub
+ call sys32_x32_rt_sigreturn
+ jmp return_from_stub
END(stub_x32_rt_sigreturn)
#endif

@@ -502,16 +498,16 @@ END(stub_x32_rt_sigreturn)
*/
ENTRY(ret_from_fork)

- LOCK ; btr $TIF_FORK,TI_flags(%r8)
+ LOCK ; btr $TIF_FORK, TI_flags(%r8)

- pushq $0x0002
- popfq # reset kernel eflags
+ pushq $0x0002
+ popfq /* reset kernel eflags */

- call schedule_tail # rdi: 'prev' task parameter
+ call schedule_tail /* rdi: 'prev' task parameter */

RESTORE_EXTRA_REGS

- testb $3, CS(%rsp) # from kernel_thread?
+ testb $3, CS(%rsp) /* from kernel_thread? */

/*
* By the time we get here, we have no idea whether our pt_regs,
@@ -522,13 +518,15 @@ ENTRY(ret_from_fork)
*/
jnz int_ret_from_sys_call

- /* We came from kernel_thread */
- /* nb: we depend on RESTORE_EXTRA_REGS above */
- movq %rbp, %rdi
- call *%rbx
- movl $0, RAX(%rsp)
+ /*
+ * We came from kernel_thread
+ * nb: we depend on RESTORE_EXTRA_REGS above
+ */
+ movq %rbp, %rdi
+ call *%rbx
+ movl $0, RAX(%rsp)
RESTORE_EXTRA_REGS
- jmp int_ret_from_sys_call
+ jmp int_ret_from_sys_call
END(ret_from_fork)

/*
@@ -539,7 +537,7 @@ END(ret_from_fork)
ENTRY(irq_entries_start)
vector=FIRST_EXTERNAL_VECTOR
.rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
- pushq $(~vector+0x80) /* Note: always in signed byte range */
+ pushq $(~vector+0x80) /* Note: always in signed byte range */
vector=vector+1
jmp common_interrupt
.align 8
@@ -569,7 +567,7 @@ END(irq_entries_start)
/* this goes to 0(%rsp) for unwinder, not for saving the value: */
SAVE_EXTRA_REGS_RBP -RBP

- leaq -RBP(%rsp),%rdi /* arg1 for \func (pointer to pt_regs) */
+ leaq -RBP(%rsp), %rdi /* arg1 for \func (pointer to pt_regs) */

testb $3, CS-RBP(%rsp)
jz 1f
@@ -582,14 +580,14 @@ END(irq_entries_start)
* a little cheaper to use a separate counter in the PDA (short of
* moving irq_enter into assembly, which would be too much work)
*/
- movq %rsp, %rsi
- incl PER_CPU_VAR(irq_count)
- cmovzq PER_CPU_VAR(irq_stack_ptr),%rsp
- pushq %rsi
+ movq %rsp, %rsi
+ incl PER_CPU_VAR(irq_count)
+ cmovzq PER_CPU_VAR(irq_stack_ptr), %rsp
+ pushq %rsi
/* We entered an interrupt context - irqs are off: */
TRACE_IRQS_OFF

- call \func
+ call \func
.endm

/*
@@ -599,36 +597,35 @@ END(irq_entries_start)
.p2align CONFIG_X86_L1_CACHE_SHIFT
common_interrupt:
ASM_CLAC
- addq $-0x80,(%rsp) /* Adjust vector to [-256,-1] range */
+ addq $-0x80, (%rsp) /* Adjust vector to [-256, -1] range */
interrupt do_IRQ
/* 0(%rsp): old RSP */
ret_from_intr:
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- decl PER_CPU_VAR(irq_count)
+ decl PER_CPU_VAR(irq_count)

/* Restore saved previous stack */
- popq %rsi
+ popq %rsi
/* return code expects complete pt_regs - adjust rsp accordingly: */
- leaq -RBP(%rsi),%rsp
+ leaq -RBP(%rsi), %rsp

testb $3, CS(%rsp)
jz retint_kernel
/* Interrupt came from user space */
retint_user:
GET_THREAD_INFO(%rcx)
- /*
- * %rcx: thread info. Interrupts off.
- */
+
+ /* %rcx: thread info. Interrupts are off. */
retint_with_reschedule:
- movl $_TIF_WORK_MASK,%edi
+ movl $_TIF_WORK_MASK, %edi
retint_check:
LOCKDEP_SYS_EXIT_IRQ
- movl TI_flags(%rcx),%edx
- andl %edi,%edx
- jnz retint_careful
+ movl TI_flags(%rcx), %edx
+ andl %edi, %edx
+ jnz retint_careful

-retint_swapgs: /* return to user-space */
+retint_swapgs: /* return to user-space */
/*
* The iretq could re-enable interrupts:
*/
@@ -643,9 +640,9 @@ retint_swapgs: /* return to user-space */
#ifdef CONFIG_PREEMPT
/* Interrupts are off */
/* Check if we need preemption */
- bt $9,EFLAGS(%rsp) /* interrupts were off? */
+ bt $9, EFLAGS(%rsp) /* were interrupts off? */
jnc 1f
-0: cmpl $0,PER_CPU_VAR(__preempt_count)
+0: cmpl $0, PER_CPU_VAR(__preempt_count)
jnz 1f
call preempt_schedule_irq
jmp 0b
@@ -671,8 +668,8 @@ ENTRY(native_iret)
* 64-bit mode SS:RSP on the exception stack is always valid.
*/
#ifdef CONFIG_X86_ESPFIX64
- testb $4,(SS-RIP)(%rsp)
- jnz native_irq_return_ldt
+ testb $4, (SS-RIP)(%rsp)
+ jnz native_irq_return_ldt
#endif

.global native_irq_return_iret
@@ -687,59 +684,59 @@ ENTRY(native_iret)

#ifdef CONFIG_X86_ESPFIX64
native_irq_return_ldt:
- pushq %rax
- pushq %rdi
+ pushq %rax
+ pushq %rdi
SWAPGS
- movq PER_CPU_VAR(espfix_waddr),%rdi
- movq %rax,(0*8)(%rdi) /* RAX */
- movq (2*8)(%rsp),%rax /* RIP */
- movq %rax,(1*8)(%rdi)
- movq (3*8)(%rsp),%rax /* CS */
- movq %rax,(2*8)(%rdi)
- movq (4*8)(%rsp),%rax /* RFLAGS */
- movq %rax,(3*8)(%rdi)
- movq (6*8)(%rsp),%rax /* SS */
- movq %rax,(5*8)(%rdi)
- movq (5*8)(%rsp),%rax /* RSP */
- movq %rax,(4*8)(%rdi)
- andl $0xffff0000,%eax
- popq %rdi
- orq PER_CPU_VAR(espfix_stack),%rax
+ movq PER_CPU_VAR(espfix_waddr), %rdi
+ movq %rax, (0*8)(%rdi) /* RAX */
+ movq (2*8)(%rsp), %rax /* RIP */
+ movq %rax, (1*8)(%rdi)
+ movq (3*8)(%rsp), %rax /* CS */
+ movq %rax, (2*8)(%rdi)
+ movq (4*8)(%rsp), %rax /* RFLAGS */
+ movq %rax, (3*8)(%rdi)
+ movq (6*8)(%rsp), %rax /* SS */
+ movq %rax, (5*8)(%rdi)
+ movq (5*8)(%rsp), %rax /* RSP */
+ movq %rax, (4*8)(%rdi)
+ andl $0xffff0000, %eax
+ popq %rdi
+ orq PER_CPU_VAR(espfix_stack), %rax
SWAPGS
- movq %rax,%rsp
- popq %rax
- jmp native_irq_return_iret
+ movq %rax, %rsp
+ popq %rax
+ jmp native_irq_return_iret
#endif

/* edi: workmask, edx: work */
retint_careful:
- bt $TIF_NEED_RESCHED,%edx
- jnc retint_signal
+ bt $TIF_NEED_RESCHED, %edx
+ jnc retint_signal
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
- pushq %rdi
+ pushq %rdi
SCHEDULE_USER
- popq %rdi
+ popq %rdi
GET_THREAD_INFO(%rcx)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- jmp retint_check
+ jmp retint_check

retint_signal:
- testl $_TIF_DO_NOTIFY_MASK,%edx
- jz retint_swapgs
+ testl $_TIF_DO_NOTIFY_MASK, %edx
+ jz retint_swapgs
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
SAVE_EXTRA_REGS
- movq $-1,ORIG_RAX(%rsp)
- xorl %esi,%esi # oldset
- movq %rsp,%rdi # &pt_regs
- call do_notify_resume
+ movq $-1, ORIG_RAX(%rsp)
+ xorl %esi, %esi /* oldset */
+ movq %rsp, %rdi /* &pt_regs */
+ call do_notify_resume
RESTORE_EXTRA_REGS
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
GET_THREAD_INFO(%rcx)
- jmp retint_with_reschedule
+ jmp retint_with_reschedule

END(common_interrupt)

@@ -749,10 +746,10 @@ END(common_interrupt)
.macro apicinterrupt3 num sym do_sym
ENTRY(\sym)
ASM_CLAC
- pushq $~(\num)
+ pushq $~(\num)
.Lcommon_\sym:
interrupt \do_sym
- jmp ret_from_intr
+ jmp ret_from_intr
END(\sym)
.endm

@@ -774,60 +771,45 @@ trace_apicinterrupt \num \sym
.endm

#ifdef CONFIG_SMP
-apicinterrupt3 IRQ_MOVE_CLEANUP_VECTOR \
- irq_move_cleanup_interrupt smp_irq_move_cleanup_interrupt
-apicinterrupt3 REBOOT_VECTOR \
- reboot_interrupt smp_reboot_interrupt
+apicinterrupt3 IRQ_MOVE_CLEANUP_VECTOR irq_move_cleanup_interrupt smp_irq_move_cleanup_interrupt
+apicinterrupt3 REBOOT_VECTOR reboot_interrupt smp_reboot_interrupt
#endif

#ifdef CONFIG_X86_UV
-apicinterrupt3 UV_BAU_MESSAGE \
- uv_bau_message_intr1 uv_bau_message_interrupt
+apicinterrupt3 UV_BAU_MESSAGE uv_bau_message_intr1 uv_bau_message_interrupt
#endif
-apicinterrupt LOCAL_TIMER_VECTOR \
- apic_timer_interrupt smp_apic_timer_interrupt
-apicinterrupt X86_PLATFORM_IPI_VECTOR \
- x86_platform_ipi smp_x86_platform_ipi
+
+apicinterrupt LOCAL_TIMER_VECTOR apic_timer_interrupt smp_apic_timer_interrupt
+apicinterrupt X86_PLATFORM_IPI_VECTOR x86_platform_ipi smp_x86_platform_ipi

#ifdef CONFIG_HAVE_KVM
-apicinterrupt3 POSTED_INTR_VECTOR \
- kvm_posted_intr_ipi smp_kvm_posted_intr_ipi
-apicinterrupt3 POSTED_INTR_WAKEUP_VECTOR \
- kvm_posted_intr_wakeup_ipi smp_kvm_posted_intr_wakeup_ipi
+apicinterrupt3 POSTED_INTR_VECTOR kvm_posted_intr_ipi smp_kvm_posted_intr_ipi
+apicinterrupt3 POSTED_INTR_WAKEUP_VECTOR kvm_posted_intr_wakeup_ipi smp_kvm_posted_intr_wakeup_ipi
#endif

#ifdef CONFIG_X86_MCE_THRESHOLD
-apicinterrupt THRESHOLD_APIC_VECTOR \
- threshold_interrupt smp_threshold_interrupt
+apicinterrupt THRESHOLD_APIC_VECTOR threshold_interrupt smp_threshold_interrupt
#endif

#ifdef CONFIG_X86_MCE_AMD
-apicinterrupt DEFERRED_ERROR_VECTOR \
- deferred_error_interrupt smp_deferred_error_interrupt
+apicinterrupt DEFERRED_ERROR_VECTOR deferred_error_interrupt smp_deferred_error_interrupt
#endif

#ifdef CONFIG_X86_THERMAL_VECTOR
-apicinterrupt THERMAL_APIC_VECTOR \
- thermal_interrupt smp_thermal_interrupt
+apicinterrupt THERMAL_APIC_VECTOR thermal_interrupt smp_thermal_interrupt
#endif

#ifdef CONFIG_SMP
-apicinterrupt CALL_FUNCTION_SINGLE_VECTOR \
- call_function_single_interrupt smp_call_function_single_interrupt
-apicinterrupt CALL_FUNCTION_VECTOR \
- call_function_interrupt smp_call_function_interrupt
-apicinterrupt RESCHEDULE_VECTOR \
- reschedule_interrupt smp_reschedule_interrupt
+apicinterrupt CALL_FUNCTION_SINGLE_VECTOR call_function_single_interrupt smp_call_function_single_interrupt
+apicinterrupt CALL_FUNCTION_VECTOR call_function_interrupt smp_call_function_interrupt
+apicinterrupt RESCHEDULE_VECTOR reschedule_interrupt smp_reschedule_interrupt
#endif

-apicinterrupt ERROR_APIC_VECTOR \
- error_interrupt smp_error_interrupt
-apicinterrupt SPURIOUS_APIC_VECTOR \
- spurious_interrupt smp_spurious_interrupt
+apicinterrupt ERROR_APIC_VECTOR error_interrupt smp_error_interrupt
+apicinterrupt SPURIOUS_APIC_VECTOR spurious_interrupt smp_spurious_interrupt

#ifdef CONFIG_IRQ_WORK
-apicinterrupt IRQ_WORK_VECTOR \
- irq_work_interrupt smp_irq_work_interrupt
+apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt
#endif

/*
@@ -846,54 +828,54 @@ ENTRY(\sym)
PARAVIRT_ADJUST_EXCEPTION_FRAME

.ifeq \has_error_code
- pushq $-1 /* ORIG_RAX: no syscall to restart */
+ pushq $-1 /* ORIG_RAX: no syscall to restart */
.endif

ALLOC_PT_GPREGS_ON_STACK

.if \paranoid
.if \paranoid == 1
- testb $3, CS(%rsp) /* If coming from userspace, switch */
- jnz 1f /* stacks. */
+ testb $3, CS(%rsp) /* If coming from userspace, switch stacks */
+ jnz 1f
.endif
- call paranoid_entry
+ call paranoid_entry
.else
- call error_entry
+ call error_entry
.endif
/* returned flag: ebx=0: need swapgs on exit, ebx=1: don't need it */

.if \paranoid
.if \shift_ist != -1
- TRACE_IRQS_OFF_DEBUG /* reload IDT in case of recursion */
+ TRACE_IRQS_OFF_DEBUG /* reload IDT in case of recursion */
.else
TRACE_IRQS_OFF
.endif
.endif

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

.if \has_error_code
- movq ORIG_RAX(%rsp),%rsi /* get error code */
- movq $-1,ORIG_RAX(%rsp) /* no syscall to restart */
+ movq ORIG_RAX(%rsp), %rsi /* get error code */
+ movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
.else
- xorl %esi,%esi /* no error code */
+ xorl %esi, %esi /* no error code */
.endif

.if \shift_ist != -1
- subq $EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
+ subq $EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
.endif

- call \do_sym
+ call \do_sym

.if \shift_ist != -1
- addq $EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
+ addq $EXCEPTION_STKSZ, CPU_TSS_IST(\shift_ist)
.endif

/* these procedures expect "no swapgs" flag in ebx */
.if \paranoid
- jmp paranoid_exit
+ jmp paranoid_exit
.else
- jmp error_exit
+ jmp error_exit
.endif

.if \paranoid == 1
@@ -903,25 +885,25 @@ ENTRY(\sym)
* run in real process context if user_mode(regs).
*/
1:
- call error_entry
+ call error_entry


- movq %rsp,%rdi /* pt_regs pointer */
- call sync_regs
- movq %rax,%rsp /* switch stack */
+ movq %rsp, %rdi /* pt_regs pointer */
+ call sync_regs
+ movq %rax, %rsp /* switch stack */

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

.if \has_error_code
- movq ORIG_RAX(%rsp),%rsi /* get error code */
- movq $-1,ORIG_RAX(%rsp) /* no syscall to restart */
+ movq ORIG_RAX(%rsp), %rsi /* get error code */
+ movq $-1, ORIG_RAX(%rsp) /* no syscall to restart */
.else
- xorl %esi,%esi /* no error code */
+ xorl %esi, %esi /* no error code */
.endif

- call \do_sym
+ call \do_sym

- jmp error_exit /* %ebx: no swapgs flag */
+ jmp error_exit /* %ebx: no swapgs flag */
.endif
END(\sym)
.endm
@@ -937,55 +919,57 @@ idtentry \sym \do_sym has_error_code=\has_error_code
.endm
#endif

-idtentry divide_error do_divide_error has_error_code=0
-idtentry overflow do_overflow has_error_code=0
-idtentry bounds do_bounds has_error_code=0
-idtentry invalid_op do_invalid_op has_error_code=0
-idtentry device_not_available do_device_not_available has_error_code=0
-idtentry double_fault do_double_fault has_error_code=1 paranoid=2
-idtentry coprocessor_segment_overrun do_coprocessor_segment_overrun has_error_code=0
-idtentry invalid_TSS do_invalid_TSS has_error_code=1
-idtentry segment_not_present do_segment_not_present has_error_code=1
-idtentry spurious_interrupt_bug do_spurious_interrupt_bug has_error_code=0
-idtentry coprocessor_error do_coprocessor_error has_error_code=0
-idtentry alignment_check do_alignment_check has_error_code=1
-idtentry simd_coprocessor_error do_simd_coprocessor_error has_error_code=0
-
-
- /* Reload gs selector with exception handling */
- /* edi: new selector */
+idtentry divide_error do_divide_error has_error_code=0
+idtentry overflow do_overflow has_error_code=0
+idtentry bounds do_bounds has_error_code=0
+idtentry invalid_op do_invalid_op has_error_code=0
+idtentry device_not_available do_device_not_available has_error_code=0
+idtentry double_fault do_double_fault has_error_code=1 paranoid=2
+idtentry coprocessor_segment_overrun do_coprocessor_segment_overrun has_error_code=0
+idtentry invalid_TSS do_invalid_TSS has_error_code=1
+idtentry segment_not_present do_segment_not_present has_error_code=1
+idtentry spurious_interrupt_bug do_spurious_interrupt_bug has_error_code=0
+idtentry coprocessor_error do_coprocessor_error has_error_code=0
+idtentry alignment_check do_alignment_check has_error_code=1
+idtentry simd_coprocessor_error do_simd_coprocessor_error has_error_code=0
+
+
+ /*
+ * Reload gs selector with exception handling
+ * edi: new selector
+ */
ENTRY(native_load_gs_index)
pushfq
DISABLE_INTERRUPTS(CLBR_ANY & ~CLBR_RDI)
SWAPGS
gs_change:
- movl %edi,%gs
-2: mfence /* workaround */
+ movl %edi, %gs
+2: mfence /* workaround */
SWAPGS
popfq
ret
END(native_load_gs_index)

- _ASM_EXTABLE(gs_change,bad_gs)
- .section .fixup,"ax"
+ _ASM_EXTABLE(gs_change, bad_gs)
+ .section .fixup, "ax"
/* running with kernelgs */
bad_gs:
- SWAPGS /* switch back to user gs */
- xorl %eax,%eax
- movl %eax,%gs
- jmp 2b
+ SWAPGS /* switch back to user gs */
+ xorl %eax, %eax
+ movl %eax, %gs
+ jmp 2b
.previous

/* Call softirq on interrupt stack. Interrupts are off. */
ENTRY(do_softirq_own_stack)
- pushq %rbp
- mov %rsp,%rbp
- incl PER_CPU_VAR(irq_count)
- cmove PER_CPU_VAR(irq_stack_ptr),%rsp
- push %rbp # backlink for old unwinder
- call __do_softirq
+ pushq %rbp
+ mov %rsp, %rbp
+ incl PER_CPU_VAR(irq_count)
+ cmove PER_CPU_VAR(irq_stack_ptr), %rsp
+ push %rbp /* frame pointer backlink */
+ call __do_softirq
leaveq
- decl PER_CPU_VAR(irq_count)
+ decl PER_CPU_VAR(irq_count)
ret
END(do_softirq_own_stack)

@@ -1005,23 +989,24 @@ idtentry xen_hypervisor_callback xen_do_hypervisor_callback has_error_code=0
* existing activation in its critical region -- if so, we pop the current
* activation and restart the handler using the previous one.
*/
-ENTRY(xen_do_hypervisor_callback) # do_hypervisor_callback(struct *pt_regs)
+ENTRY(xen_do_hypervisor_callback) /* do_hypervisor_callback(struct *pt_regs) */
+
/*
* Since we don't modify %rdi, evtchn_do_upall(struct *pt_regs) will
* see the correct pointer to the pt_regs
*/
- movq %rdi, %rsp # we don't return, adjust the stack frame
-11: incl PER_CPU_VAR(irq_count)
- movq %rsp,%rbp
- cmovzq PER_CPU_VAR(irq_stack_ptr),%rsp
- pushq %rbp # backlink for old unwinder
- call xen_evtchn_do_upcall
- popq %rsp
- decl PER_CPU_VAR(irq_count)
+ movq %rdi, %rsp /* we don't return, adjust the stack frame */
+11: incl PER_CPU_VAR(irq_count)
+ movq %rsp, %rbp
+ cmovzq PER_CPU_VAR(irq_stack_ptr), %rsp
+ pushq %rbp /* frame pointer backlink */
+ call xen_evtchn_do_upcall
+ popq %rsp
+ decl PER_CPU_VAR(irq_count)
#ifndef CONFIG_PREEMPT
- call xen_maybe_preempt_hcall
+ call xen_maybe_preempt_hcall
#endif
- jmp error_exit
+ jmp error_exit
END(xen_do_hypervisor_callback)

/*
@@ -1038,35 +1023,35 @@ END(xen_do_hypervisor_callback)
* with its current contents: any discrepancy means we in category 1.
*/
ENTRY(xen_failsafe_callback)
- movl %ds,%ecx
- cmpw %cx,0x10(%rsp)
- jne 1f
- movl %es,%ecx
- cmpw %cx,0x18(%rsp)
- jne 1f
- movl %fs,%ecx
- cmpw %cx,0x20(%rsp)
- jne 1f
- movl %gs,%ecx
- cmpw %cx,0x28(%rsp)
- jne 1f
+ movl %ds, %ecx
+ cmpw %cx, 0x10(%rsp)
+ jne 1f
+ movl %es, %ecx
+ cmpw %cx, 0x18(%rsp)
+ jne 1f
+ movl %fs, %ecx
+ cmpw %cx, 0x20(%rsp)
+ jne 1f
+ movl %gs, %ecx
+ cmpw %cx, 0x28(%rsp)
+ jne 1f
/* All segments match their saved values => Category 2 (Bad IRET). */
- movq (%rsp),%rcx
- movq 8(%rsp),%r11
- addq $0x30,%rsp
- pushq $0 /* RIP */
- pushq %r11
- pushq %rcx
- jmp general_protection
+ movq (%rsp), %rcx
+ movq 8(%rsp), %r11
+ addq $0x30, %rsp
+ pushq $0 /* RIP */
+ pushq %r11
+ pushq %rcx
+ jmp general_protection
1: /* Segment mismatch => Category 1 (Bad segment). Retry the IRET. */
- movq (%rsp),%rcx
- movq 8(%rsp),%r11
- addq $0x30,%rsp
- pushq $-1 /* orig_ax = -1 => not a system call */
+ movq (%rsp), %rcx
+ movq 8(%rsp), %r11
+ addq $0x30, %rsp
+ pushq $-1 /* orig_ax = -1 => not a system call */
ALLOC_PT_GPREGS_ON_STACK
SAVE_C_REGS
SAVE_EXTRA_REGS
- jmp error_exit
+ jmp error_exit
END(xen_failsafe_callback)

apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
@@ -1079,21 +1064,25 @@ apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
hyperv_callback_vector hyperv_vector_handler
#endif /* CONFIG_HYPERV */

-idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
-idtentry int3 do_int3 has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
-idtentry stack_segment do_stack_segment has_error_code=1
+idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
+idtentry int3 do_int3 has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK
+idtentry stack_segment do_stack_segment has_error_code=1
+
#ifdef CONFIG_XEN
-idtentry xen_debug do_debug has_error_code=0
-idtentry xen_int3 do_int3 has_error_code=0
-idtentry xen_stack_segment do_stack_segment has_error_code=1
+idtentry xen_debug do_debug has_error_code=0
+idtentry xen_int3 do_int3 has_error_code=0
+idtentry xen_stack_segment do_stack_segment has_error_code=1
#endif
-idtentry general_protection do_general_protection has_error_code=1
-trace_idtentry page_fault do_page_fault has_error_code=1
+
+idtentry general_protection do_general_protection has_error_code=1
+trace_idtentry page_fault do_page_fault has_error_code=1
+
#ifdef CONFIG_KVM_GUEST
-idtentry async_page_fault do_async_page_fault has_error_code=1
+idtentry async_page_fault do_async_page_fault has_error_code=1
#endif
+
#ifdef CONFIG_X86_MCE
-idtentry machine_check has_error_code=0 paranoid=1 do_sym=*machine_check_vector(%rip)
+idtentry machine_check has_error_code=0 paranoid=1 do_sym=*machine_check_vector(%rip)
#endif

/*
@@ -1105,13 +1094,13 @@ ENTRY(paranoid_entry)
cld
SAVE_C_REGS 8
SAVE_EXTRA_REGS 8
- movl $1,%ebx
- movl $MSR_GS_BASE,%ecx
+ movl $1, %ebx
+ movl $MSR_GS_BASE, %ecx
rdmsr
- testl %edx,%edx
- js 1f /* negative -> in kernel */
+ testl %edx, %edx
+ js 1f /* negative -> in kernel */
SWAPGS
- xorl %ebx,%ebx
+ xorl %ebx, %ebx
1: ret
END(paranoid_entry)

@@ -1124,16 +1113,17 @@ END(paranoid_entry)
* in syscall entry), so checking for preemption here would
* be complicated. Fortunately, we there's no good reason
* to try to handle preemption here.
+ *
+ * On entry, ebx is "no swapgs" flag (1: don't need swapgs, 0: need it)
*/
-/* On entry, ebx is "no swapgs" flag (1: don't need swapgs, 0: need it) */
ENTRY(paranoid_exit)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF_DEBUG
- testl %ebx,%ebx /* swapgs needed? */
- jnz paranoid_exit_no_swapgs
+ testl %ebx, %ebx /* swapgs needed? */
+ jnz paranoid_exit_no_swapgs
TRACE_IRQS_IRETQ
SWAPGS_UNSAFE_STACK
- jmp paranoid_exit_restore
+ jmp paranoid_exit_restore
paranoid_exit_no_swapgs:
TRACE_IRQS_IRETQ_DEBUG
paranoid_exit_restore:
@@ -1151,7 +1141,7 @@ ENTRY(error_entry)
cld
SAVE_C_REGS 8
SAVE_EXTRA_REGS 8
- xorl %ebx,%ebx
+ xorl %ebx, %ebx
testb $3, CS+8(%rsp)
jz error_kernelspace
error_swapgs:
@@ -1167,41 +1157,41 @@ ENTRY(error_entry)
* for these here too.
*/
error_kernelspace:
- incl %ebx
- leaq native_irq_return_iret(%rip),%rcx
- cmpq %rcx,RIP+8(%rsp)
- je error_bad_iret
- movl %ecx,%eax /* zero extend */
- cmpq %rax,RIP+8(%rsp)
- je bstep_iret
- cmpq $gs_change,RIP+8(%rsp)
- je error_swapgs
- jmp error_sti
+ incl %ebx
+ leaq native_irq_return_iret(%rip), %rcx
+ cmpq %rcx, RIP+8(%rsp)
+ je error_bad_iret
+ movl %ecx, %eax /* zero extend */
+ cmpq %rax, RIP+8(%rsp)
+ je bstep_iret
+ cmpq $gs_change, RIP+8(%rsp)
+ je error_swapgs
+ jmp error_sti

bstep_iret:
/* Fix truncated RIP */
- movq %rcx,RIP+8(%rsp)
+ movq %rcx, RIP+8(%rsp)
/* fall through */

error_bad_iret:
SWAPGS
- mov %rsp,%rdi
- call fixup_bad_iret
- mov %rax,%rsp
- decl %ebx /* Return to usergs */
- jmp error_sti
+ mov %rsp, %rdi
+ call fixup_bad_iret
+ mov %rax, %rsp
+ decl %ebx /* Return to usergs */
+ jmp error_sti
END(error_entry)


/* On entry, ebx is "no swapgs" flag (1: don't need swapgs, 0: need it) */
ENTRY(error_exit)
- movl %ebx,%eax
+ movl %ebx, %eax
RESTORE_EXTRA_REGS
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- testl %eax,%eax
- jnz retint_kernel
- jmp retint_user
+ testl %eax, %eax
+ jnz retint_kernel
+ jmp retint_user
END(error_exit)

/* Runs on exception stack */
@@ -1240,21 +1230,21 @@ ENTRY(nmi)
*/

/* Use %rdx as our temp variable throughout */
- pushq %rdx
+ pushq %rdx

/*
* If %cs was not the kernel segment, then the NMI triggered in user
* space, which means it is definitely not nested.
*/
- cmpl $__KERNEL_CS, 16(%rsp)
- jne first_nmi
+ cmpl $__KERNEL_CS, 16(%rsp)
+ jne first_nmi

/*
* Check the special variable on the stack to see if NMIs are
* executing.
*/
- cmpl $1, -8(%rsp)
- je nested_nmi
+ cmpl $1, -8(%rsp)
+ je nested_nmi

/*
* Now test if the previous stack was an NMI stack.
@@ -1268,6 +1258,7 @@ ENTRY(nmi)
cmpq %rdx, 4*8(%rsp)
/* If the stack pointer is above the NMI stack, this is a normal NMI */
ja first_nmi
+
subq $EXCEPTION_STKSZ, %rdx
cmpq %rdx, 4*8(%rsp)
/* If it is below the NMI stack, it is a normal NMI */
@@ -1280,29 +1271,29 @@ ENTRY(nmi)
* It's about to repeat the NMI handler, so we are fine
* with ignoring this one.
*/
- movq $repeat_nmi, %rdx
- cmpq 8(%rsp), %rdx
- ja 1f
- movq $end_repeat_nmi, %rdx
- cmpq 8(%rsp), %rdx
- ja nested_nmi_out
+ movq $repeat_nmi, %rdx
+ cmpq 8(%rsp), %rdx
+ ja 1f
+ movq $end_repeat_nmi, %rdx
+ cmpq 8(%rsp), %rdx
+ ja nested_nmi_out

1:
/* Set up the interrupted NMIs stack to jump to repeat_nmi */
- leaq -1*8(%rsp), %rdx
- movq %rdx, %rsp
- leaq -10*8(%rsp), %rdx
- pushq $__KERNEL_DS
- pushq %rdx
+ leaq -1*8(%rsp), %rdx
+ movq %rdx, %rsp
+ leaq -10*8(%rsp), %rdx
+ pushq $__KERNEL_DS
+ pushq %rdx
pushfq
- pushq $__KERNEL_CS
- pushq $repeat_nmi
+ pushq $__KERNEL_CS
+ pushq $repeat_nmi

/* Put stack back */
- addq $(6*8), %rsp
+ addq $(6*8), %rsp

nested_nmi_out:
- popq %rdx
+ popq %rdx

/* No need to check faults here */
INTERRUPT_RETURN
@@ -1344,19 +1335,17 @@ ENTRY(nmi)
* is also used by nested NMIs and can not be trusted on exit.
*/
/* Do not pop rdx, nested NMIs will corrupt that part of the stack */
- movq (%rsp), %rdx
+ movq (%rsp), %rdx

/* Set the NMI executing variable on the stack. */
- pushq $1
+ pushq $1

- /*
- * Leave room for the "copied" frame
- */
- subq $(5*8), %rsp
+ /* Leave room for the "copied" frame */
+ subq $(5*8), %rsp

/* Copy the stack frame to the Saved frame */
.rept 5
- pushq 11*8(%rsp)
+ pushq 11*8(%rsp)
.endr

/* Everything up to here is safe from nested NMIs */
@@ -1376,14 +1365,14 @@ ENTRY(nmi)
* is benign for the non-repeat case, where 1 was pushed just above
* to this very stack slot).
*/
- movq $1, 10*8(%rsp)
+ movq $1, 10*8(%rsp)

/* Make another copy, this one may be modified by nested NMIs */
- addq $(10*8), %rsp
+ addq $(10*8), %rsp
.rept 5
- pushq -6*8(%rsp)
+ pushq -6*8(%rsp)
.endr
- subq $(5*8), %rsp
+ subq $(5*8), %rsp
end_repeat_nmi:

/*
@@ -1391,7 +1380,7 @@ ENTRY(nmi)
* NMI if the first NMI took an exception and reset our iret stack
* so that we repeat another NMI.
*/
- pushq $-1 /* ORIG_RAX: no syscall to restart */
+ pushq $-1 /* ORIG_RAX: no syscall to restart */
ALLOC_PT_GPREGS_ON_STACK

/*
@@ -1401,7 +1390,7 @@ ENTRY(nmi)
* setting NEED_RESCHED or anything that normal interrupts and
* exceptions might do.
*/
- call paranoid_entry
+ call paranoid_entry

/*
* Save off the CR2 register. If we take a page fault in the NMI then
@@ -1412,21 +1401,21 @@ ENTRY(nmi)
* origin fault. Save it off and restore it if it changes.
* Use the r12 callee-saved register.
*/
- movq %cr2, %r12
+ movq %cr2, %r12

/* paranoidentry do_nmi, 0; without TRACE_IRQS_OFF */
- movq %rsp,%rdi
- movq $-1,%rsi
- call do_nmi
+ movq %rsp, %rdi
+ movq $-1, %rsi
+ call do_nmi

/* Did the NMI take a page fault? Restore cr2 if it did */
- movq %cr2, %rcx
- cmpq %rcx, %r12
- je 1f
- movq %r12, %cr2
+ movq %cr2, %rcx
+ cmpq %rcx, %r12
+ je 1f
+ movq %r12, %cr2
1:
- testl %ebx,%ebx /* swapgs needed? */
- jnz nmi_restore
+ testl %ebx, %ebx /* swapgs needed? */
+ jnz nmi_restore
nmi_swapgs:
SWAPGS_UNSAFE_STACK
nmi_restore:
@@ -1436,12 +1425,11 @@ ENTRY(nmi)
REMOVE_PT_GPREGS_FROM_STACK 6*8

/* Clear the NMI executing stack variable */
- movq $0, 5*8(%rsp)
+ movq $0, 5*8(%rsp)
INTERRUPT_RETURN
END(nmi)

ENTRY(ignore_sysret)
- mov $-ENOSYS,%eax
+ mov $-ENOSYS, %eax
sysret
END(ignore_sysret)
-
--
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