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@@ -1,1401 +0,0 @@
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-/*
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- *
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- * Copyright (C) 1991, 1992 Linus Torvalds
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- */
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-
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-/*
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- * entry.S contains the system-call and fault low-level handling routines.
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- * This also contains the timer-interrupt handler, as well as all interrupts
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- * and faults that can result in a task-switch.
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- *
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- * NOTE: This code handles signal-recognition, which happens every time
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- * after a timer-interrupt and after each system call.
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- *
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- * I changed all the .align's to 4 (16 byte alignment), as that's faster
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- * on a 486.
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- *
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- * Stack layout in 'syscall_exit':
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- * ptrace needs to have all regs on the stack.
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- * if the order here is changed, it needs to be
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- * updated in fork.c:copy_process, signal.c:do_signal,
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- * ptrace.c and ptrace.h
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- *
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- * 0(%esp) - %ebx
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- * 4(%esp) - %ecx
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- * 8(%esp) - %edx
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- * C(%esp) - %esi
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- * 10(%esp) - %edi
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- * 14(%esp) - %ebp
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- * 18(%esp) - %eax
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- * 1C(%esp) - %ds
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- * 20(%esp) - %es
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- * 24(%esp) - %fs
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- * 28(%esp) - %gs saved iff !CONFIG_X86_32_LAZY_GS
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- * 2C(%esp) - orig_eax
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- * 30(%esp) - %eip
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- * 34(%esp) - %cs
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- * 38(%esp) - %eflags
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- * 3C(%esp) - %oldesp
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- * 40(%esp) - %oldss
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- *
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- * "current" is in register %ebx during any slow entries.
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- */
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-
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-#include <linux/linkage.h>
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-#include <linux/err.h>
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-#include <asm/thread_info.h>
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-#include <asm/irqflags.h>
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-#include <asm/errno.h>
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-#include <asm/segment.h>
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-#include <asm/smp.h>
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-#include <asm/page_types.h>
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-#include <asm/percpu.h>
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-#include <asm/dwarf2.h>
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-#include <asm/processor-flags.h>
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-#include <asm/ftrace.h>
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-#include <asm/irq_vectors.h>
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-#include <asm/cpufeature.h>
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-#include <asm/alternative-asm.h>
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-#include <asm/asm.h>
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-#include <asm/smap.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 sysenter_audit syscall_trace_entry
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-#define sysexit_audit syscall_exit_work
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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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-/*
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- * We use macros for low-level operations which need to be overridden
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- * for paravirtualization. The following will never clobber any registers:
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- * INTERRUPT_RETURN (aka. "iret")
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- * GET_CR0_INTO_EAX (aka. "movl %cr0, %eax")
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- * ENABLE_INTERRUPTS_SYSEXIT (aka "sti; sysexit").
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- *
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- * For DISABLE_INTERRUPTS/ENABLE_INTERRUPTS (aka "cli"/"sti"), you must
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- * specify what registers can be overwritten (CLBR_NONE, CLBR_EAX/EDX/ECX/ANY).
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- * Allowing a register to be clobbered can shrink the paravirt replacement
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- * enough to patch inline, increasing performance.
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- */
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-
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-#ifdef CONFIG_PREEMPT
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-#define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF
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-#else
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-#define preempt_stop(clobbers)
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-#define resume_kernel restore_all
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-#endif
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-
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-.macro TRACE_IRQS_IRET
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-#ifdef CONFIG_TRACE_IRQFLAGS
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- testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off?
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- jz 1f
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- TRACE_IRQS_ON
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-1:
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-#endif
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-.endm
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-
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-/*
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- * User gs save/restore
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- *
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- * %gs is used for userland TLS and kernel only uses it for stack
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- * canary which is required to be at %gs:20 by gcc. Read the comment
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- * at the top of stackprotector.h for more info.
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- *
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- * Local labels 98 and 99 are used.
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- */
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-#ifdef CONFIG_X86_32_LAZY_GS
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-
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- /* unfortunately push/pop can't be no-op */
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-.macro PUSH_GS
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- pushl_cfi $0
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-.endm
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-.macro POP_GS pop=0
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- addl $(4 + \pop), %esp
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- CFI_ADJUST_CFA_OFFSET -(4 + \pop)
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-.endm
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-.macro POP_GS_EX
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-.endm
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-
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- /* all the rest are no-op */
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-.macro PTGS_TO_GS
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-.endm
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-.macro PTGS_TO_GS_EX
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-.endm
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-.macro GS_TO_REG reg
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-.endm
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-.macro REG_TO_PTGS reg
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-.endm
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-.macro SET_KERNEL_GS reg
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-.endm
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-
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-#else /* CONFIG_X86_32_LAZY_GS */
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-
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-.macro PUSH_GS
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- pushl_cfi %gs
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- /*CFI_REL_OFFSET gs, 0*/
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-.endm
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-
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-.macro POP_GS pop=0
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-98: popl_cfi %gs
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- /*CFI_RESTORE gs*/
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- .if \pop <> 0
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- add $\pop, %esp
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- CFI_ADJUST_CFA_OFFSET -\pop
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- .endif
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-.endm
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-.macro POP_GS_EX
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-.pushsection .fixup, "ax"
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-99: movl $0, (%esp)
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- jmp 98b
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-.popsection
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- _ASM_EXTABLE(98b,99b)
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-.endm
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-
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-.macro PTGS_TO_GS
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-98: mov PT_GS(%esp), %gs
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-.endm
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-.macro PTGS_TO_GS_EX
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-.pushsection .fixup, "ax"
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-99: movl $0, PT_GS(%esp)
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- jmp 98b
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-.popsection
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- _ASM_EXTABLE(98b,99b)
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-.endm
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-
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-.macro GS_TO_REG reg
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- movl %gs, \reg
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- /*CFI_REGISTER gs, \reg*/
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-.endm
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-.macro REG_TO_PTGS reg
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- movl \reg, PT_GS(%esp)
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- /*CFI_REL_OFFSET gs, PT_GS*/
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-.endm
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-.macro SET_KERNEL_GS reg
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- movl $(__KERNEL_STACK_CANARY), \reg
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- movl \reg, %gs
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-.endm
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-
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-#endif /* CONFIG_X86_32_LAZY_GS */
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-
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-.macro SAVE_ALL
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- cld
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- PUSH_GS
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- pushl_cfi %fs
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- /*CFI_REL_OFFSET fs, 0;*/
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- pushl_cfi %es
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- /*CFI_REL_OFFSET es, 0;*/
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- pushl_cfi %ds
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- /*CFI_REL_OFFSET ds, 0;*/
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- pushl_cfi %eax
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- CFI_REL_OFFSET eax, 0
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- pushl_cfi %ebp
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- CFI_REL_OFFSET ebp, 0
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- pushl_cfi %edi
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- CFI_REL_OFFSET edi, 0
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- pushl_cfi %esi
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- CFI_REL_OFFSET esi, 0
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- pushl_cfi %edx
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- CFI_REL_OFFSET edx, 0
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- pushl_cfi %ecx
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- CFI_REL_OFFSET ecx, 0
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- pushl_cfi %ebx
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- CFI_REL_OFFSET ebx, 0
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- movl $(__USER_DS), %edx
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- movl %edx, %ds
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- movl %edx, %es
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- movl $(__KERNEL_PERCPU), %edx
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- movl %edx, %fs
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- SET_KERNEL_GS %edx
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-.endm
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-
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-.macro RESTORE_INT_REGS
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- popl_cfi %ebx
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- CFI_RESTORE ebx
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- popl_cfi %ecx
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- CFI_RESTORE ecx
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- popl_cfi %edx
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- CFI_RESTORE edx
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- popl_cfi %esi
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- CFI_RESTORE esi
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- popl_cfi %edi
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- CFI_RESTORE edi
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- popl_cfi %ebp
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- CFI_RESTORE ebp
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- popl_cfi %eax
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- CFI_RESTORE eax
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-.endm
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-
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-.macro RESTORE_REGS pop=0
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- RESTORE_INT_REGS
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-1: popl_cfi %ds
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- /*CFI_RESTORE ds;*/
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-2: popl_cfi %es
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- /*CFI_RESTORE es;*/
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-3: popl_cfi %fs
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- /*CFI_RESTORE fs;*/
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- POP_GS \pop
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-.pushsection .fixup, "ax"
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-4: movl $0, (%esp)
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- jmp 1b
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-5: movl $0, (%esp)
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- jmp 2b
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-6: movl $0, (%esp)
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- jmp 3b
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-.popsection
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- _ASM_EXTABLE(1b,4b)
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- _ASM_EXTABLE(2b,5b)
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- _ASM_EXTABLE(3b,6b)
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- POP_GS_EX
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-.endm
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-
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-.macro RING0_INT_FRAME
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- CFI_STARTPROC simple
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- CFI_SIGNAL_FRAME
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- CFI_DEF_CFA esp, 3*4
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- /*CFI_OFFSET cs, -2*4;*/
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- CFI_OFFSET eip, -3*4
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-.endm
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-
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-.macro RING0_EC_FRAME
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- CFI_STARTPROC simple
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- CFI_SIGNAL_FRAME
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- CFI_DEF_CFA esp, 4*4
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- /*CFI_OFFSET cs, -2*4;*/
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- CFI_OFFSET eip, -3*4
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-.endm
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-
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-.macro RING0_PTREGS_FRAME
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- CFI_STARTPROC simple
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- CFI_SIGNAL_FRAME
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- CFI_DEF_CFA esp, PT_OLDESP-PT_EBX
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- /*CFI_OFFSET cs, PT_CS-PT_OLDESP;*/
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- CFI_OFFSET eip, PT_EIP-PT_OLDESP
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- /*CFI_OFFSET es, PT_ES-PT_OLDESP;*/
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- /*CFI_OFFSET ds, PT_DS-PT_OLDESP;*/
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- CFI_OFFSET eax, PT_EAX-PT_OLDESP
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- CFI_OFFSET ebp, PT_EBP-PT_OLDESP
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- CFI_OFFSET edi, PT_EDI-PT_OLDESP
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- CFI_OFFSET esi, PT_ESI-PT_OLDESP
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- CFI_OFFSET edx, PT_EDX-PT_OLDESP
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- CFI_OFFSET ecx, PT_ECX-PT_OLDESP
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- CFI_OFFSET ebx, PT_EBX-PT_OLDESP
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-.endm
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-
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-ENTRY(ret_from_fork)
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- CFI_STARTPROC
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- pushl_cfi %eax
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- call schedule_tail
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- GET_THREAD_INFO(%ebp)
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- popl_cfi %eax
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- pushl_cfi $0x0202 # Reset kernel eflags
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- popfl_cfi
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- jmp syscall_exit
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- CFI_ENDPROC
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-END(ret_from_fork)
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-
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-ENTRY(ret_from_kernel_thread)
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- CFI_STARTPROC
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- pushl_cfi %eax
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- call schedule_tail
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- GET_THREAD_INFO(%ebp)
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- popl_cfi %eax
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- pushl_cfi $0x0202 # Reset kernel eflags
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- popfl_cfi
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- movl PT_EBP(%esp),%eax
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- call *PT_EBX(%esp)
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- movl $0,PT_EAX(%esp)
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- jmp syscall_exit
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- CFI_ENDPROC
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-ENDPROC(ret_from_kernel_thread)
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-
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-/*
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- * Return to user mode is not as complex as all this looks,
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- * but we want the default path for a system call return to
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- * go as quickly as possible which is why some of this is
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- * less clear than it otherwise should be.
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- */
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-
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- # userspace resumption stub bypassing syscall exit tracing
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- ALIGN
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- RING0_PTREGS_FRAME
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-ret_from_exception:
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- preempt_stop(CLBR_ANY)
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-ret_from_intr:
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- GET_THREAD_INFO(%ebp)
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-#ifdef CONFIG_VM86
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- movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS
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- movb PT_CS(%esp), %al
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- andl $(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax
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-#else
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- /*
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- * We can be coming here from child spawned by kernel_thread().
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- */
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- movl PT_CS(%esp), %eax
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- andl $SEGMENT_RPL_MASK, %eax
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-#endif
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- cmpl $USER_RPL, %eax
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- jb resume_kernel # not returning to v8086 or userspace
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-
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-ENTRY(resume_userspace)
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- LOCKDEP_SYS_EXIT
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- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
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- # setting need_resched or sigpending
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- # between sampling and the iret
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- TRACE_IRQS_OFF
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- movl TI_flags(%ebp), %ecx
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- andl $_TIF_WORK_MASK, %ecx # is there any work to be done on
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- # int/exception return?
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- jne work_pending
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- jmp restore_all
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-END(ret_from_exception)
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-
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-#ifdef CONFIG_PREEMPT
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-ENTRY(resume_kernel)
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- DISABLE_INTERRUPTS(CLBR_ANY)
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-need_resched:
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- cmpl $0,PER_CPU_VAR(__preempt_count)
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- jnz restore_all
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- testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ?
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- jz restore_all
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- call preempt_schedule_irq
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- jmp need_resched
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-END(resume_kernel)
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-#endif
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- CFI_ENDPROC
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-
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-/* SYSENTER_RETURN points to after the "sysenter" instruction in
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- the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
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-
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- # sysenter call handler stub
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-ENTRY(ia32_sysenter_target)
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- CFI_STARTPROC simple
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- CFI_SIGNAL_FRAME
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- CFI_DEF_CFA esp, 0
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- CFI_REGISTER esp, ebp
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- movl TSS_sysenter_sp0(%esp),%esp
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-sysenter_past_esp:
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- /*
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- * Interrupts are disabled here, but we can't trace it until
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- * enough kernel state to call TRACE_IRQS_OFF can be called - but
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- * we immediately enable interrupts at that point anyway.
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- */
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- pushl_cfi $__USER_DS
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- /*CFI_REL_OFFSET ss, 0*/
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- pushl_cfi %ebp
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- CFI_REL_OFFSET esp, 0
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- pushfl_cfi
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- orl $X86_EFLAGS_IF, (%esp)
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- pushl_cfi $__USER_CS
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- /*CFI_REL_OFFSET cs, 0*/
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- /*
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- * Push current_thread_info()->sysenter_return to the stack.
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- * A tiny bit of offset fixup is necessary: TI_sysenter_return
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- * is relative to thread_info, which is at the bottom of the
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- * kernel stack page. 4*4 means the 4 words pushed above;
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- * TOP_OF_KERNEL_STACK_PADDING takes us to the top of the stack;
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- * and THREAD_SIZE takes us to the bottom.
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- */
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- pushl_cfi ((TI_sysenter_return) - THREAD_SIZE + TOP_OF_KERNEL_STACK_PADDING + 4*4)(%esp)
|
|
|
- CFI_REL_OFFSET eip, 0
|
|
|
-
|
|
|
- pushl_cfi %eax
|
|
|
- SAVE_ALL
|
|
|
- ENABLE_INTERRUPTS(CLBR_NONE)
|
|
|
-
|
|
|
-/*
|
|
|
- * Load the potential sixth argument from user stack.
|
|
|
- * Careful about security.
|
|
|
- */
|
|
|
- cmpl $__PAGE_OFFSET-3,%ebp
|
|
|
- jae syscall_fault
|
|
|
- ASM_STAC
|
|
|
-1: movl (%ebp),%ebp
|
|
|
- ASM_CLAC
|
|
|
- movl %ebp,PT_EBP(%esp)
|
|
|
- _ASM_EXTABLE(1b,syscall_fault)
|
|
|
-
|
|
|
- GET_THREAD_INFO(%ebp)
|
|
|
-
|
|
|
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%ebp)
|
|
|
- jnz sysenter_audit
|
|
|
-sysenter_do_call:
|
|
|
- cmpl $(NR_syscalls), %eax
|
|
|
- jae sysenter_badsys
|
|
|
- call *sys_call_table(,%eax,4)
|
|
|
-sysenter_after_call:
|
|
|
- movl %eax,PT_EAX(%esp)
|
|
|
- LOCKDEP_SYS_EXIT
|
|
|
- DISABLE_INTERRUPTS(CLBR_ANY)
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl TI_flags(%ebp), %ecx
|
|
|
- testl $_TIF_ALLWORK_MASK, %ecx
|
|
|
- jnz sysexit_audit
|
|
|
-sysenter_exit:
|
|
|
-/* if something modifies registers it must also disable sysexit */
|
|
|
- movl PT_EIP(%esp), %edx
|
|
|
- movl PT_OLDESP(%esp), %ecx
|
|
|
- xorl %ebp,%ebp
|
|
|
- TRACE_IRQS_ON
|
|
|
-1: mov PT_FS(%esp), %fs
|
|
|
- PTGS_TO_GS
|
|
|
- ENABLE_INTERRUPTS_SYSEXIT
|
|
|
-
|
|
|
-#ifdef CONFIG_AUDITSYSCALL
|
|
|
-sysenter_audit:
|
|
|
- testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
|
|
|
- jnz syscall_trace_entry
|
|
|
- /* movl PT_EAX(%esp), %eax already set, syscall number: 1st arg to audit */
|
|
|
- movl PT_EBX(%esp), %edx /* ebx/a0: 2nd arg to audit */
|
|
|
- /* movl PT_ECX(%esp), %ecx already set, a1: 3nd arg to audit */
|
|
|
- pushl_cfi PT_ESI(%esp) /* a3: 5th arg */
|
|
|
- pushl_cfi PT_EDX+4(%esp) /* a2: 4th arg */
|
|
|
- call __audit_syscall_entry
|
|
|
- popl_cfi %ecx /* get that remapped edx off the stack */
|
|
|
- popl_cfi %ecx /* get that remapped esi off the stack */
|
|
|
- movl PT_EAX(%esp),%eax /* reload syscall number */
|
|
|
- jmp sysenter_do_call
|
|
|
-
|
|
|
-sysexit_audit:
|
|
|
- testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %ecx
|
|
|
- jnz syscall_exit_work
|
|
|
- TRACE_IRQS_ON
|
|
|
- ENABLE_INTERRUPTS(CLBR_ANY)
|
|
|
- movl %eax,%edx /* second arg, syscall return value */
|
|
|
- cmpl $-MAX_ERRNO,%eax /* is it an error ? */
|
|
|
- setbe %al /* 1 if so, 0 if not */
|
|
|
- movzbl %al,%eax /* zero-extend that */
|
|
|
- call __audit_syscall_exit
|
|
|
- DISABLE_INTERRUPTS(CLBR_ANY)
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl TI_flags(%ebp), %ecx
|
|
|
- testl $(_TIF_ALLWORK_MASK & ~_TIF_SYSCALL_AUDIT), %ecx
|
|
|
- jnz syscall_exit_work
|
|
|
- movl PT_EAX(%esp),%eax /* reload syscall return value */
|
|
|
- jmp sysenter_exit
|
|
|
-#endif
|
|
|
-
|
|
|
- CFI_ENDPROC
|
|
|
-.pushsection .fixup,"ax"
|
|
|
-2: movl $0,PT_FS(%esp)
|
|
|
- jmp 1b
|
|
|
-.popsection
|
|
|
- _ASM_EXTABLE(1b,2b)
|
|
|
- PTGS_TO_GS_EX
|
|
|
-ENDPROC(ia32_sysenter_target)
|
|
|
-
|
|
|
- # system call handler stub
|
|
|
-ENTRY(system_call)
|
|
|
- RING0_INT_FRAME # can't unwind into user space anyway
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi %eax # save orig_eax
|
|
|
- SAVE_ALL
|
|
|
- GET_THREAD_INFO(%ebp)
|
|
|
- # system call tracing in operation / emulation
|
|
|
- testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags(%ebp)
|
|
|
- jnz syscall_trace_entry
|
|
|
- cmpl $(NR_syscalls), %eax
|
|
|
- jae syscall_badsys
|
|
|
-syscall_call:
|
|
|
- call *sys_call_table(,%eax,4)
|
|
|
-syscall_after_call:
|
|
|
- movl %eax,PT_EAX(%esp) # store the return value
|
|
|
-syscall_exit:
|
|
|
- LOCKDEP_SYS_EXIT
|
|
|
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
|
|
|
- # setting need_resched or sigpending
|
|
|
- # between sampling and the iret
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl TI_flags(%ebp), %ecx
|
|
|
- testl $_TIF_ALLWORK_MASK, %ecx # current->work
|
|
|
- jnz syscall_exit_work
|
|
|
-
|
|
|
-restore_all:
|
|
|
- TRACE_IRQS_IRET
|
|
|
-restore_all_notrace:
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
- movl PT_EFLAGS(%esp), %eax # mix EFLAGS, SS and CS
|
|
|
- # Warning: PT_OLDSS(%esp) contains the wrong/random values if we
|
|
|
- # are returning to the kernel.
|
|
|
- # See comments in process.c:copy_thread() for details.
|
|
|
- movb PT_OLDSS(%esp), %ah
|
|
|
- movb PT_CS(%esp), %al
|
|
|
- andl $(X86_EFLAGS_VM | (SEGMENT_TI_MASK << 8) | SEGMENT_RPL_MASK), %eax
|
|
|
- cmpl $((SEGMENT_LDT << 8) | USER_RPL), %eax
|
|
|
- CFI_REMEMBER_STATE
|
|
|
- je ldt_ss # returning to user-space with LDT SS
|
|
|
-#endif
|
|
|
-restore_nocheck:
|
|
|
- RESTORE_REGS 4 # skip orig_eax/error_code
|
|
|
-irq_return:
|
|
|
- INTERRUPT_RETURN
|
|
|
-.section .fixup,"ax"
|
|
|
-ENTRY(iret_exc)
|
|
|
- pushl $0 # no error code
|
|
|
- pushl $do_iret_error
|
|
|
- jmp error_code
|
|
|
-.previous
|
|
|
- _ASM_EXTABLE(irq_return,iret_exc)
|
|
|
-
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
- CFI_RESTORE_STATE
|
|
|
-ldt_ss:
|
|
|
-#ifdef CONFIG_PARAVIRT
|
|
|
- /*
|
|
|
- * The kernel can't run on a non-flat stack if paravirt mode
|
|
|
- * is active. Rather than try to fixup the high bits of
|
|
|
- * ESP, bypass this code entirely. This may break DOSemu
|
|
|
- * and/or Wine support in a paravirt VM, although the option
|
|
|
- * is still available to implement the setting of the high
|
|
|
- * 16-bits in the INTERRUPT_RETURN paravirt-op.
|
|
|
- */
|
|
|
- cmpl $0, pv_info+PARAVIRT_enabled
|
|
|
- jne restore_nocheck
|
|
|
-#endif
|
|
|
-
|
|
|
-/*
|
|
|
- * Setup and switch to ESPFIX stack
|
|
|
- *
|
|
|
- * We're returning to userspace with a 16 bit stack. The CPU will not
|
|
|
- * restore the high word of ESP for us on executing iret... This is an
|
|
|
- * "official" bug of all the x86-compatible CPUs, which we can work
|
|
|
- * around to make dosemu and wine happy. We do this by preloading the
|
|
|
- * high word of ESP with the high word of the userspace ESP while
|
|
|
- * compensating for the offset by changing to the ESPFIX segment with
|
|
|
- * a base address that matches for the difference.
|
|
|
- */
|
|
|
-#define GDT_ESPFIX_SS PER_CPU_VAR(gdt_page) + (GDT_ENTRY_ESPFIX_SS * 8)
|
|
|
- mov %esp, %edx /* load kernel esp */
|
|
|
- mov PT_OLDESP(%esp), %eax /* load userspace esp */
|
|
|
- mov %dx, %ax /* eax: new kernel esp */
|
|
|
- sub %eax, %edx /* offset (low word is 0) */
|
|
|
- shr $16, %edx
|
|
|
- mov %dl, GDT_ESPFIX_SS + 4 /* bits 16..23 */
|
|
|
- mov %dh, GDT_ESPFIX_SS + 7 /* bits 24..31 */
|
|
|
- pushl_cfi $__ESPFIX_SS
|
|
|
- pushl_cfi %eax /* new kernel esp */
|
|
|
- /* Disable interrupts, but do not irqtrace this section: we
|
|
|
- * will soon execute iret and the tracer was already set to
|
|
|
- * the irqstate after the iret */
|
|
|
- DISABLE_INTERRUPTS(CLBR_EAX)
|
|
|
- lss (%esp), %esp /* switch to espfix segment */
|
|
|
- CFI_ADJUST_CFA_OFFSET -8
|
|
|
- jmp restore_nocheck
|
|
|
-#endif
|
|
|
- CFI_ENDPROC
|
|
|
-ENDPROC(system_call)
|
|
|
-
|
|
|
- # perform work that needs to be done immediately before resumption
|
|
|
- ALIGN
|
|
|
- RING0_PTREGS_FRAME # can't unwind into user space anyway
|
|
|
-work_pending:
|
|
|
- testb $_TIF_NEED_RESCHED, %cl
|
|
|
- jz work_notifysig
|
|
|
-work_resched:
|
|
|
- call schedule
|
|
|
- LOCKDEP_SYS_EXIT
|
|
|
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
|
|
|
- # setting need_resched or sigpending
|
|
|
- # between sampling and the iret
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl TI_flags(%ebp), %ecx
|
|
|
- andl $_TIF_WORK_MASK, %ecx # is there any work to be done other
|
|
|
- # than syscall tracing?
|
|
|
- jz restore_all
|
|
|
- testb $_TIF_NEED_RESCHED, %cl
|
|
|
- jnz work_resched
|
|
|
-
|
|
|
-work_notifysig: # deal with pending signals and
|
|
|
- # notify-resume requests
|
|
|
-#ifdef CONFIG_VM86
|
|
|
- testl $X86_EFLAGS_VM, PT_EFLAGS(%esp)
|
|
|
- movl %esp, %eax
|
|
|
- jnz work_notifysig_v86 # returning to kernel-space or
|
|
|
- # vm86-space
|
|
|
-1:
|
|
|
-#else
|
|
|
- movl %esp, %eax
|
|
|
-#endif
|
|
|
- TRACE_IRQS_ON
|
|
|
- ENABLE_INTERRUPTS(CLBR_NONE)
|
|
|
- movb PT_CS(%esp), %bl
|
|
|
- andb $SEGMENT_RPL_MASK, %bl
|
|
|
- cmpb $USER_RPL, %bl
|
|
|
- jb resume_kernel
|
|
|
- xorl %edx, %edx
|
|
|
- call do_notify_resume
|
|
|
- jmp resume_userspace
|
|
|
-
|
|
|
-#ifdef CONFIG_VM86
|
|
|
- ALIGN
|
|
|
-work_notifysig_v86:
|
|
|
- pushl_cfi %ecx # save ti_flags for do_notify_resume
|
|
|
- call save_v86_state # %eax contains pt_regs pointer
|
|
|
- popl_cfi %ecx
|
|
|
- movl %eax, %esp
|
|
|
- jmp 1b
|
|
|
-#endif
|
|
|
-END(work_pending)
|
|
|
-
|
|
|
- # perform syscall exit tracing
|
|
|
- ALIGN
|
|
|
-syscall_trace_entry:
|
|
|
- movl $-ENOSYS,PT_EAX(%esp)
|
|
|
- movl %esp, %eax
|
|
|
- call syscall_trace_enter
|
|
|
- /* What it returned is what we'll actually use. */
|
|
|
- cmpl $(NR_syscalls), %eax
|
|
|
- jnae syscall_call
|
|
|
- jmp syscall_exit
|
|
|
-END(syscall_trace_entry)
|
|
|
-
|
|
|
- # perform syscall exit tracing
|
|
|
- ALIGN
|
|
|
-syscall_exit_work:
|
|
|
- testl $_TIF_WORK_SYSCALL_EXIT, %ecx
|
|
|
- jz work_pending
|
|
|
- TRACE_IRQS_ON
|
|
|
- ENABLE_INTERRUPTS(CLBR_ANY) # could let syscall_trace_leave() call
|
|
|
- # schedule() instead
|
|
|
- movl %esp, %eax
|
|
|
- call syscall_trace_leave
|
|
|
- jmp resume_userspace
|
|
|
-END(syscall_exit_work)
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
- RING0_INT_FRAME # can't unwind into user space anyway
|
|
|
-syscall_fault:
|
|
|
- ASM_CLAC
|
|
|
- GET_THREAD_INFO(%ebp)
|
|
|
- movl $-EFAULT,PT_EAX(%esp)
|
|
|
- jmp resume_userspace
|
|
|
-END(syscall_fault)
|
|
|
-
|
|
|
-syscall_badsys:
|
|
|
- movl $-ENOSYS,%eax
|
|
|
- jmp syscall_after_call
|
|
|
-END(syscall_badsys)
|
|
|
-
|
|
|
-sysenter_badsys:
|
|
|
- movl $-ENOSYS,%eax
|
|
|
- jmp sysenter_after_call
|
|
|
-END(sysenter_badsys)
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
-.macro FIXUP_ESPFIX_STACK
|
|
|
-/*
|
|
|
- * Switch back for ESPFIX stack to the normal zerobased stack
|
|
|
- *
|
|
|
- * We can't call C functions using the ESPFIX stack. This code reads
|
|
|
- * the high word of the segment base from the GDT and swiches to the
|
|
|
- * normal stack and adjusts ESP with the matching offset.
|
|
|
- */
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
- /* fixup the stack */
|
|
|
- mov GDT_ESPFIX_SS + 4, %al /* bits 16..23 */
|
|
|
- mov GDT_ESPFIX_SS + 7, %ah /* bits 24..31 */
|
|
|
- shl $16, %eax
|
|
|
- addl %esp, %eax /* the adjusted stack pointer */
|
|
|
- pushl_cfi $__KERNEL_DS
|
|
|
- pushl_cfi %eax
|
|
|
- lss (%esp), %esp /* switch to the normal stack segment */
|
|
|
- CFI_ADJUST_CFA_OFFSET -8
|
|
|
-#endif
|
|
|
-.endm
|
|
|
-.macro UNWIND_ESPFIX_STACK
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
- movl %ss, %eax
|
|
|
- /* see if on espfix stack */
|
|
|
- cmpw $__ESPFIX_SS, %ax
|
|
|
- jne 27f
|
|
|
- movl $__KERNEL_DS, %eax
|
|
|
- movl %eax, %ds
|
|
|
- movl %eax, %es
|
|
|
- /* switch to normal stack */
|
|
|
- FIXUP_ESPFIX_STACK
|
|
|
-27:
|
|
|
-#endif
|
|
|
-.endm
|
|
|
-
|
|
|
-/*
|
|
|
- * Build the entry stubs with some assembler magic.
|
|
|
- * We pack 1 stub into every 8-byte block.
|
|
|
- */
|
|
|
- .align 8
|
|
|
-ENTRY(irq_entries_start)
|
|
|
- RING0_INT_FRAME
|
|
|
- vector=FIRST_EXTERNAL_VECTOR
|
|
|
- .rept (FIRST_SYSTEM_VECTOR - FIRST_EXTERNAL_VECTOR)
|
|
|
- pushl_cfi $(~vector+0x80) /* Note: always in signed byte range */
|
|
|
- vector=vector+1
|
|
|
- jmp common_interrupt
|
|
|
- CFI_ADJUST_CFA_OFFSET -4
|
|
|
- .align 8
|
|
|
- .endr
|
|
|
-END(irq_entries_start)
|
|
|
-
|
|
|
-/*
|
|
|
- * the CPU automatically disables interrupts when executing an IRQ vector,
|
|
|
- * so IRQ-flags tracing has to follow that:
|
|
|
- */
|
|
|
- .p2align CONFIG_X86_L1_CACHE_SHIFT
|
|
|
-common_interrupt:
|
|
|
- ASM_CLAC
|
|
|
- addl $-0x80,(%esp) /* Adjust vector into the [-256,-1] range */
|
|
|
- SAVE_ALL
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl %esp,%eax
|
|
|
- call do_IRQ
|
|
|
- jmp ret_from_intr
|
|
|
-ENDPROC(common_interrupt)
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
-#define BUILD_INTERRUPT3(name, nr, fn) \
|
|
|
-ENTRY(name) \
|
|
|
- RING0_INT_FRAME; \
|
|
|
- ASM_CLAC; \
|
|
|
- pushl_cfi $~(nr); \
|
|
|
- SAVE_ALL; \
|
|
|
- TRACE_IRQS_OFF \
|
|
|
- movl %esp,%eax; \
|
|
|
- call fn; \
|
|
|
- jmp ret_from_intr; \
|
|
|
- CFI_ENDPROC; \
|
|
|
-ENDPROC(name)
|
|
|
-
|
|
|
-
|
|
|
-#ifdef CONFIG_TRACING
|
|
|
-#define TRACE_BUILD_INTERRUPT(name, nr) \
|
|
|
- BUILD_INTERRUPT3(trace_##name, nr, smp_trace_##name)
|
|
|
-#else
|
|
|
-#define TRACE_BUILD_INTERRUPT(name, nr)
|
|
|
-#endif
|
|
|
-
|
|
|
-#define BUILD_INTERRUPT(name, nr) \
|
|
|
- BUILD_INTERRUPT3(name, nr, smp_##name); \
|
|
|
- TRACE_BUILD_INTERRUPT(name, nr)
|
|
|
-
|
|
|
-/* The include is where all of the SMP etc. interrupts come from */
|
|
|
-#include <asm/entry_arch.h>
|
|
|
-
|
|
|
-ENTRY(coprocessor_error)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_coprocessor_error
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(coprocessor_error)
|
|
|
-
|
|
|
-ENTRY(simd_coprocessor_error)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
-#ifdef CONFIG_X86_INVD_BUG
|
|
|
- /* AMD 486 bug: invd from userspace calls exception 19 instead of #GP */
|
|
|
- ALTERNATIVE "pushl_cfi $do_general_protection", \
|
|
|
- "pushl $do_simd_coprocessor_error", \
|
|
|
- X86_FEATURE_XMM
|
|
|
-#else
|
|
|
- pushl_cfi $do_simd_coprocessor_error
|
|
|
-#endif
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(simd_coprocessor_error)
|
|
|
-
|
|
|
-ENTRY(device_not_available)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $-1 # mark this as an int
|
|
|
- pushl_cfi $do_device_not_available
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(device_not_available)
|
|
|
-
|
|
|
-#ifdef CONFIG_PARAVIRT
|
|
|
-ENTRY(native_iret)
|
|
|
- iret
|
|
|
- _ASM_EXTABLE(native_iret, iret_exc)
|
|
|
-END(native_iret)
|
|
|
-
|
|
|
-ENTRY(native_irq_enable_sysexit)
|
|
|
- sti
|
|
|
- sysexit
|
|
|
-END(native_irq_enable_sysexit)
|
|
|
-#endif
|
|
|
-
|
|
|
-ENTRY(overflow)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_overflow
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(overflow)
|
|
|
-
|
|
|
-ENTRY(bounds)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_bounds
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(bounds)
|
|
|
-
|
|
|
-ENTRY(invalid_op)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_invalid_op
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(invalid_op)
|
|
|
-
|
|
|
-ENTRY(coprocessor_segment_overrun)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_coprocessor_segment_overrun
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(coprocessor_segment_overrun)
|
|
|
-
|
|
|
-ENTRY(invalid_TSS)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_invalid_TSS
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(invalid_TSS)
|
|
|
-
|
|
|
-ENTRY(segment_not_present)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_segment_not_present
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(segment_not_present)
|
|
|
-
|
|
|
-ENTRY(stack_segment)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_stack_segment
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(stack_segment)
|
|
|
-
|
|
|
-ENTRY(alignment_check)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_alignment_check
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(alignment_check)
|
|
|
-
|
|
|
-ENTRY(divide_error)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0 # no error code
|
|
|
- pushl_cfi $do_divide_error
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(divide_error)
|
|
|
-
|
|
|
-#ifdef CONFIG_X86_MCE
|
|
|
-ENTRY(machine_check)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi machine_check_vector
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(machine_check)
|
|
|
-#endif
|
|
|
-
|
|
|
-ENTRY(spurious_interrupt_bug)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $0
|
|
|
- pushl_cfi $do_spurious_interrupt_bug
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(spurious_interrupt_bug)
|
|
|
-
|
|
|
-#ifdef CONFIG_XEN
|
|
|
-/* Xen doesn't set %esp to be precisely what the normal sysenter
|
|
|
- entrypoint expects, so fix it up before using the normal path. */
|
|
|
-ENTRY(xen_sysenter_target)
|
|
|
- RING0_INT_FRAME
|
|
|
- addl $5*4, %esp /* remove xen-provided frame */
|
|
|
- CFI_ADJUST_CFA_OFFSET -5*4
|
|
|
- jmp sysenter_past_esp
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
-ENTRY(xen_hypervisor_callback)
|
|
|
- CFI_STARTPROC
|
|
|
- pushl_cfi $-1 /* orig_ax = -1 => not a system call */
|
|
|
- SAVE_ALL
|
|
|
- TRACE_IRQS_OFF
|
|
|
-
|
|
|
- /* Check to see if we got the event in the critical
|
|
|
- region in xen_iret_direct, after we've reenabled
|
|
|
- events and checked for pending events. This simulates
|
|
|
- iret instruction's behaviour where it delivers a
|
|
|
- pending interrupt when enabling interrupts. */
|
|
|
- movl PT_EIP(%esp),%eax
|
|
|
- cmpl $xen_iret_start_crit,%eax
|
|
|
- jb 1f
|
|
|
- cmpl $xen_iret_end_crit,%eax
|
|
|
- jae 1f
|
|
|
-
|
|
|
- jmp xen_iret_crit_fixup
|
|
|
-
|
|
|
-ENTRY(xen_do_upcall)
|
|
|
-1: mov %esp, %eax
|
|
|
- call xen_evtchn_do_upcall
|
|
|
-#ifndef CONFIG_PREEMPT
|
|
|
- call xen_maybe_preempt_hcall
|
|
|
-#endif
|
|
|
- jmp ret_from_intr
|
|
|
- CFI_ENDPROC
|
|
|
-ENDPROC(xen_hypervisor_callback)
|
|
|
-
|
|
|
-# Hypervisor uses this for application faults while it executes.
|
|
|
-# We get here for two reasons:
|
|
|
-# 1. Fault while reloading DS, ES, FS or GS
|
|
|
-# 2. Fault while executing IRET
|
|
|
-# Category 1 we fix up by reattempting the load, and zeroing the segment
|
|
|
-# register if the load fails.
|
|
|
-# Category 2 we fix up by jumping to do_iret_error. We cannot use the
|
|
|
-# normal Linux return path in this case because if we use the IRET hypercall
|
|
|
-# to pop the stack frame we end up in an infinite loop of failsafe callbacks.
|
|
|
-# We distinguish between categories by maintaining a status value in EAX.
|
|
|
-ENTRY(xen_failsafe_callback)
|
|
|
- CFI_STARTPROC
|
|
|
- pushl_cfi %eax
|
|
|
- movl $1,%eax
|
|
|
-1: mov 4(%esp),%ds
|
|
|
-2: mov 8(%esp),%es
|
|
|
-3: mov 12(%esp),%fs
|
|
|
-4: mov 16(%esp),%gs
|
|
|
- /* EAX == 0 => Category 1 (Bad segment)
|
|
|
- EAX != 0 => Category 2 (Bad IRET) */
|
|
|
- testl %eax,%eax
|
|
|
- popl_cfi %eax
|
|
|
- lea 16(%esp),%esp
|
|
|
- CFI_ADJUST_CFA_OFFSET -16
|
|
|
- jz 5f
|
|
|
- jmp iret_exc
|
|
|
-5: pushl_cfi $-1 /* orig_ax = -1 => not a system call */
|
|
|
- SAVE_ALL
|
|
|
- jmp ret_from_exception
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
-.section .fixup,"ax"
|
|
|
-6: xorl %eax,%eax
|
|
|
- movl %eax,4(%esp)
|
|
|
- jmp 1b
|
|
|
-7: xorl %eax,%eax
|
|
|
- movl %eax,8(%esp)
|
|
|
- jmp 2b
|
|
|
-8: xorl %eax,%eax
|
|
|
- movl %eax,12(%esp)
|
|
|
- jmp 3b
|
|
|
-9: xorl %eax,%eax
|
|
|
- movl %eax,16(%esp)
|
|
|
- jmp 4b
|
|
|
-.previous
|
|
|
- _ASM_EXTABLE(1b,6b)
|
|
|
- _ASM_EXTABLE(2b,7b)
|
|
|
- _ASM_EXTABLE(3b,8b)
|
|
|
- _ASM_EXTABLE(4b,9b)
|
|
|
-ENDPROC(xen_failsafe_callback)
|
|
|
-
|
|
|
-BUILD_INTERRUPT3(xen_hvm_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
|
|
|
- xen_evtchn_do_upcall)
|
|
|
-
|
|
|
-#endif /* CONFIG_XEN */
|
|
|
-
|
|
|
-#if IS_ENABLED(CONFIG_HYPERV)
|
|
|
-
|
|
|
-BUILD_INTERRUPT3(hyperv_callback_vector, HYPERVISOR_CALLBACK_VECTOR,
|
|
|
- hyperv_vector_handler)
|
|
|
-
|
|
|
-#endif /* CONFIG_HYPERV */
|
|
|
-
|
|
|
-#ifdef CONFIG_FUNCTION_TRACER
|
|
|
-#ifdef CONFIG_DYNAMIC_FTRACE
|
|
|
-
|
|
|
-ENTRY(mcount)
|
|
|
- ret
|
|
|
-END(mcount)
|
|
|
-
|
|
|
-ENTRY(ftrace_caller)
|
|
|
- pushl %eax
|
|
|
- pushl %ecx
|
|
|
- pushl %edx
|
|
|
- pushl $0 /* Pass NULL as regs pointer */
|
|
|
- movl 4*4(%esp), %eax
|
|
|
- movl 0x4(%ebp), %edx
|
|
|
- movl function_trace_op, %ecx
|
|
|
- subl $MCOUNT_INSN_SIZE, %eax
|
|
|
-
|
|
|
-.globl ftrace_call
|
|
|
-ftrace_call:
|
|
|
- call ftrace_stub
|
|
|
-
|
|
|
- addl $4,%esp /* skip NULL pointer */
|
|
|
- popl %edx
|
|
|
- popl %ecx
|
|
|
- popl %eax
|
|
|
-ftrace_ret:
|
|
|
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
|
-.globl ftrace_graph_call
|
|
|
-ftrace_graph_call:
|
|
|
- jmp ftrace_stub
|
|
|
-#endif
|
|
|
-
|
|
|
-.globl ftrace_stub
|
|
|
-ftrace_stub:
|
|
|
- ret
|
|
|
-END(ftrace_caller)
|
|
|
-
|
|
|
-ENTRY(ftrace_regs_caller)
|
|
|
- pushf /* push flags before compare (in cs location) */
|
|
|
-
|
|
|
- /*
|
|
|
- * i386 does not save SS and ESP when coming from kernel.
|
|
|
- * Instead, to get sp, ®s->sp is used (see ptrace.h).
|
|
|
- * Unfortunately, that means eflags must be at the same location
|
|
|
- * as the current return ip is. We move the return ip into the
|
|
|
- * ip location, and move flags into the return ip location.
|
|
|
- */
|
|
|
- pushl 4(%esp) /* save return ip into ip slot */
|
|
|
-
|
|
|
- pushl $0 /* Load 0 into orig_ax */
|
|
|
- pushl %gs
|
|
|
- pushl %fs
|
|
|
- pushl %es
|
|
|
- pushl %ds
|
|
|
- pushl %eax
|
|
|
- pushl %ebp
|
|
|
- pushl %edi
|
|
|
- pushl %esi
|
|
|
- pushl %edx
|
|
|
- pushl %ecx
|
|
|
- pushl %ebx
|
|
|
-
|
|
|
- movl 13*4(%esp), %eax /* Get the saved flags */
|
|
|
- movl %eax, 14*4(%esp) /* Move saved flags into regs->flags location */
|
|
|
- /* clobbering return ip */
|
|
|
- movl $__KERNEL_CS,13*4(%esp)
|
|
|
-
|
|
|
- movl 12*4(%esp), %eax /* Load ip (1st parameter) */
|
|
|
- subl $MCOUNT_INSN_SIZE, %eax /* Adjust ip */
|
|
|
- movl 0x4(%ebp), %edx /* Load parent ip (2nd parameter) */
|
|
|
- movl function_trace_op, %ecx /* Save ftrace_pos in 3rd parameter */
|
|
|
- pushl %esp /* Save pt_regs as 4th parameter */
|
|
|
-
|
|
|
-GLOBAL(ftrace_regs_call)
|
|
|
- call ftrace_stub
|
|
|
-
|
|
|
- addl $4, %esp /* Skip pt_regs */
|
|
|
- movl 14*4(%esp), %eax /* Move flags back into cs */
|
|
|
- movl %eax, 13*4(%esp) /* Needed to keep addl from modifying flags */
|
|
|
- movl 12*4(%esp), %eax /* Get return ip from regs->ip */
|
|
|
- movl %eax, 14*4(%esp) /* Put return ip back for ret */
|
|
|
-
|
|
|
- popl %ebx
|
|
|
- popl %ecx
|
|
|
- popl %edx
|
|
|
- popl %esi
|
|
|
- popl %edi
|
|
|
- popl %ebp
|
|
|
- popl %eax
|
|
|
- popl %ds
|
|
|
- popl %es
|
|
|
- popl %fs
|
|
|
- popl %gs
|
|
|
- addl $8, %esp /* Skip orig_ax and ip */
|
|
|
- popf /* Pop flags at end (no addl to corrupt flags) */
|
|
|
- jmp ftrace_ret
|
|
|
-
|
|
|
- popf
|
|
|
- jmp ftrace_stub
|
|
|
-#else /* ! CONFIG_DYNAMIC_FTRACE */
|
|
|
-
|
|
|
-ENTRY(mcount)
|
|
|
- cmpl $__PAGE_OFFSET, %esp
|
|
|
- jb ftrace_stub /* Paging not enabled yet? */
|
|
|
-
|
|
|
- cmpl $ftrace_stub, ftrace_trace_function
|
|
|
- jnz trace
|
|
|
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
|
- cmpl $ftrace_stub, ftrace_graph_return
|
|
|
- jnz ftrace_graph_caller
|
|
|
-
|
|
|
- cmpl $ftrace_graph_entry_stub, ftrace_graph_entry
|
|
|
- jnz ftrace_graph_caller
|
|
|
-#endif
|
|
|
-.globl ftrace_stub
|
|
|
-ftrace_stub:
|
|
|
- ret
|
|
|
-
|
|
|
- /* taken from glibc */
|
|
|
-trace:
|
|
|
- pushl %eax
|
|
|
- pushl %ecx
|
|
|
- pushl %edx
|
|
|
- movl 0xc(%esp), %eax
|
|
|
- movl 0x4(%ebp), %edx
|
|
|
- subl $MCOUNT_INSN_SIZE, %eax
|
|
|
-
|
|
|
- call *ftrace_trace_function
|
|
|
-
|
|
|
- popl %edx
|
|
|
- popl %ecx
|
|
|
- popl %eax
|
|
|
- jmp ftrace_stub
|
|
|
-END(mcount)
|
|
|
-#endif /* CONFIG_DYNAMIC_FTRACE */
|
|
|
-#endif /* CONFIG_FUNCTION_TRACER */
|
|
|
-
|
|
|
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
|
|
|
-ENTRY(ftrace_graph_caller)
|
|
|
- pushl %eax
|
|
|
- pushl %ecx
|
|
|
- pushl %edx
|
|
|
- movl 0xc(%esp), %eax
|
|
|
- lea 0x4(%ebp), %edx
|
|
|
- movl (%ebp), %ecx
|
|
|
- subl $MCOUNT_INSN_SIZE, %eax
|
|
|
- call prepare_ftrace_return
|
|
|
- popl %edx
|
|
|
- popl %ecx
|
|
|
- popl %eax
|
|
|
- ret
|
|
|
-END(ftrace_graph_caller)
|
|
|
-
|
|
|
-.globl return_to_handler
|
|
|
-return_to_handler:
|
|
|
- pushl %eax
|
|
|
- pushl %edx
|
|
|
- movl %ebp, %eax
|
|
|
- call ftrace_return_to_handler
|
|
|
- movl %eax, %ecx
|
|
|
- popl %edx
|
|
|
- popl %eax
|
|
|
- jmp *%ecx
|
|
|
-#endif
|
|
|
-
|
|
|
-#ifdef CONFIG_TRACING
|
|
|
-ENTRY(trace_page_fault)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $trace_do_page_fault
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(trace_page_fault)
|
|
|
-#endif
|
|
|
-
|
|
|
-ENTRY(page_fault)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_page_fault
|
|
|
- ALIGN
|
|
|
-error_code:
|
|
|
- /* the function address is in %gs's slot on the stack */
|
|
|
- pushl_cfi %fs
|
|
|
- /*CFI_REL_OFFSET fs, 0*/
|
|
|
- pushl_cfi %es
|
|
|
- /*CFI_REL_OFFSET es, 0*/
|
|
|
- pushl_cfi %ds
|
|
|
- /*CFI_REL_OFFSET ds, 0*/
|
|
|
- pushl_cfi_reg eax
|
|
|
- pushl_cfi_reg ebp
|
|
|
- pushl_cfi_reg edi
|
|
|
- pushl_cfi_reg esi
|
|
|
- pushl_cfi_reg edx
|
|
|
- pushl_cfi_reg ecx
|
|
|
- pushl_cfi_reg ebx
|
|
|
- cld
|
|
|
- movl $(__KERNEL_PERCPU), %ecx
|
|
|
- movl %ecx, %fs
|
|
|
- UNWIND_ESPFIX_STACK
|
|
|
- GS_TO_REG %ecx
|
|
|
- movl PT_GS(%esp), %edi # get the function address
|
|
|
- movl PT_ORIG_EAX(%esp), %edx # get the error code
|
|
|
- movl $-1, PT_ORIG_EAX(%esp) # no syscall to restart
|
|
|
- REG_TO_PTGS %ecx
|
|
|
- SET_KERNEL_GS %ecx
|
|
|
- movl $(__USER_DS), %ecx
|
|
|
- movl %ecx, %ds
|
|
|
- movl %ecx, %es
|
|
|
- TRACE_IRQS_OFF
|
|
|
- movl %esp,%eax # pt_regs pointer
|
|
|
- call *%edi
|
|
|
- jmp ret_from_exception
|
|
|
- CFI_ENDPROC
|
|
|
-END(page_fault)
|
|
|
-
|
|
|
-/*
|
|
|
- * Debug traps and NMI can happen at the one SYSENTER instruction
|
|
|
- * that sets up the real kernel stack. Check here, since we can't
|
|
|
- * allow the wrong stack to be used.
|
|
|
- *
|
|
|
- * "TSS_sysenter_sp0+12" is because the NMI/debug handler will have
|
|
|
- * already pushed 3 words if it hits on the sysenter instruction:
|
|
|
- * eflags, cs and eip.
|
|
|
- *
|
|
|
- * We just load the right stack, and push the three (known) values
|
|
|
- * by hand onto the new stack - while updating the return eip past
|
|
|
- * the instruction that would have done it for sysenter.
|
|
|
- */
|
|
|
-.macro FIX_STACK offset ok label
|
|
|
- cmpw $__KERNEL_CS, 4(%esp)
|
|
|
- jne \ok
|
|
|
-\label:
|
|
|
- movl TSS_sysenter_sp0 + \offset(%esp), %esp
|
|
|
- CFI_DEF_CFA esp, 0
|
|
|
- CFI_UNDEFINED eip
|
|
|
- pushfl_cfi
|
|
|
- pushl_cfi $__KERNEL_CS
|
|
|
- pushl_cfi $sysenter_past_esp
|
|
|
- CFI_REL_OFFSET eip, 0
|
|
|
-.endm
|
|
|
-
|
|
|
-ENTRY(debug)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- cmpl $ia32_sysenter_target,(%esp)
|
|
|
- jne debug_stack_correct
|
|
|
- FIX_STACK 12, debug_stack_correct, debug_esp_fix_insn
|
|
|
-debug_stack_correct:
|
|
|
- pushl_cfi $-1 # mark this as an int
|
|
|
- SAVE_ALL
|
|
|
- TRACE_IRQS_OFF
|
|
|
- xorl %edx,%edx # error code 0
|
|
|
- movl %esp,%eax # pt_regs pointer
|
|
|
- call do_debug
|
|
|
- jmp ret_from_exception
|
|
|
- CFI_ENDPROC
|
|
|
-END(debug)
|
|
|
-
|
|
|
-/*
|
|
|
- * NMI is doubly nasty. It can happen _while_ we're handling
|
|
|
- * a debug fault, and the debug fault hasn't yet been able to
|
|
|
- * clear up the stack. So we first check whether we got an
|
|
|
- * NMI on the sysenter entry path, but after that we need to
|
|
|
- * check whether we got an NMI on the debug path where the debug
|
|
|
- * fault happened on the sysenter path.
|
|
|
- */
|
|
|
-ENTRY(nmi)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
- pushl_cfi %eax
|
|
|
- movl %ss, %eax
|
|
|
- cmpw $__ESPFIX_SS, %ax
|
|
|
- popl_cfi %eax
|
|
|
- je nmi_espfix_stack
|
|
|
-#endif
|
|
|
- cmpl $ia32_sysenter_target,(%esp)
|
|
|
- je nmi_stack_fixup
|
|
|
- pushl_cfi %eax
|
|
|
- movl %esp,%eax
|
|
|
- /* Do not access memory above the end of our stack page,
|
|
|
- * it might not exist.
|
|
|
- */
|
|
|
- andl $(THREAD_SIZE-1),%eax
|
|
|
- cmpl $(THREAD_SIZE-20),%eax
|
|
|
- popl_cfi %eax
|
|
|
- jae nmi_stack_correct
|
|
|
- cmpl $ia32_sysenter_target,12(%esp)
|
|
|
- je nmi_debug_stack_check
|
|
|
-nmi_stack_correct:
|
|
|
- /* We have a RING0_INT_FRAME here */
|
|
|
- pushl_cfi %eax
|
|
|
- SAVE_ALL
|
|
|
- xorl %edx,%edx # zero error code
|
|
|
- movl %esp,%eax # pt_regs pointer
|
|
|
- call do_nmi
|
|
|
- jmp restore_all_notrace
|
|
|
- CFI_ENDPROC
|
|
|
-
|
|
|
-nmi_stack_fixup:
|
|
|
- RING0_INT_FRAME
|
|
|
- FIX_STACK 12, nmi_stack_correct, 1
|
|
|
- jmp nmi_stack_correct
|
|
|
-
|
|
|
-nmi_debug_stack_check:
|
|
|
- /* We have a RING0_INT_FRAME here */
|
|
|
- cmpw $__KERNEL_CS,16(%esp)
|
|
|
- jne nmi_stack_correct
|
|
|
- cmpl $debug,(%esp)
|
|
|
- jb nmi_stack_correct
|
|
|
- cmpl $debug_esp_fix_insn,(%esp)
|
|
|
- ja nmi_stack_correct
|
|
|
- FIX_STACK 24, nmi_stack_correct, 1
|
|
|
- jmp nmi_stack_correct
|
|
|
-
|
|
|
-#ifdef CONFIG_X86_ESPFIX32
|
|
|
-nmi_espfix_stack:
|
|
|
- /* We have a RING0_INT_FRAME here.
|
|
|
- *
|
|
|
- * create the pointer to lss back
|
|
|
- */
|
|
|
- pushl_cfi %ss
|
|
|
- pushl_cfi %esp
|
|
|
- addl $4, (%esp)
|
|
|
- /* copy the iret frame of 12 bytes */
|
|
|
- .rept 3
|
|
|
- pushl_cfi 16(%esp)
|
|
|
- .endr
|
|
|
- pushl_cfi %eax
|
|
|
- SAVE_ALL
|
|
|
- FIXUP_ESPFIX_STACK # %eax == %esp
|
|
|
- xorl %edx,%edx # zero error code
|
|
|
- call do_nmi
|
|
|
- RESTORE_REGS
|
|
|
- lss 12+4(%esp), %esp # back to espfix stack
|
|
|
- CFI_ADJUST_CFA_OFFSET -24
|
|
|
- jmp irq_return
|
|
|
-#endif
|
|
|
- CFI_ENDPROC
|
|
|
-END(nmi)
|
|
|
-
|
|
|
-ENTRY(int3)
|
|
|
- RING0_INT_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $-1 # mark this as an int
|
|
|
- SAVE_ALL
|
|
|
- TRACE_IRQS_OFF
|
|
|
- xorl %edx,%edx # zero error code
|
|
|
- movl %esp,%eax # pt_regs pointer
|
|
|
- call do_int3
|
|
|
- jmp ret_from_exception
|
|
|
- CFI_ENDPROC
|
|
|
-END(int3)
|
|
|
-
|
|
|
-ENTRY(general_protection)
|
|
|
- RING0_EC_FRAME
|
|
|
- pushl_cfi $do_general_protection
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(general_protection)
|
|
|
-
|
|
|
-#ifdef CONFIG_KVM_GUEST
|
|
|
-ENTRY(async_page_fault)
|
|
|
- RING0_EC_FRAME
|
|
|
- ASM_CLAC
|
|
|
- pushl_cfi $do_async_page_fault
|
|
|
- jmp error_code
|
|
|
- CFI_ENDPROC
|
|
|
-END(async_page_fault)
|
|
|
-#endif
|
|
|
-
|