extra-y := head.o init_task_32.o vmlinux.lds
-obj-y := process_32.o signal_32.o entry.o traps_32.o irq_32.o \
+obj-y := process_32.o signal_32.o entry_32.o traps_32.o irq_32.o \
ptrace_32.o time_32.o ioport_32.o ldt_32.o setup_32.o i8259_32.o sys_i386_32.o \
pci-dma_32.o i386_ksyms_32.o i387_32.o bootflag.o e820_32.o\
quirks.o i8237.o topology.o alternative.o i8253_32.o tsc.o
+++ /dev/null
-/*
- * linux/arch/i386/entry.S
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- */
-
-/*
- * entry.S contains the system-call and fault low-level handling routines.
- * This also contains the timer-interrupt handler, as well as all interrupts
- * and faults that can result in a task-switch.
- *
- * NOTE: This code handles signal-recognition, which happens every time
- * after a timer-interrupt and after each system call.
- *
- * I changed all the .align's to 4 (16 byte alignment), as that's faster
- * on a 486.
- *
- * Stack layout in 'syscall_exit':
- * ptrace needs to have all regs on the stack.
- * if the order here is changed, it needs to be
- * updated in fork.c:copy_process, signal.c:do_signal,
- * ptrace.c and ptrace.h
- *
- * 0(%esp) - %ebx
- * 4(%esp) - %ecx
- * 8(%esp) - %edx
- * C(%esp) - %esi
- * 10(%esp) - %edi
- * 14(%esp) - %ebp
- * 18(%esp) - %eax
- * 1C(%esp) - %ds
- * 20(%esp) - %es
- * 24(%esp) - %fs
- * 28(%esp) - orig_eax
- * 2C(%esp) - %eip
- * 30(%esp) - %cs
- * 34(%esp) - %eflags
- * 38(%esp) - %oldesp
- * 3C(%esp) - %oldss
- *
- * "current" is in register %ebx during any slow entries.
- */
-
-#include <linux/linkage.h>
-#include <asm/thread_info.h>
-#include <asm/irqflags.h>
-#include <asm/errno.h>
-#include <asm/segment.h>
-#include <asm/smp.h>
-#include <asm/page.h>
-#include <asm/desc.h>
-#include <asm/percpu.h>
-#include <asm/dwarf2.h>
-#include "irq_vectors.h"
-
-/*
- * We use macros for low-level operations which need to be overridden
- * for paravirtualization. The following will never clobber any registers:
- * INTERRUPT_RETURN (aka. "iret")
- * GET_CR0_INTO_EAX (aka. "movl %cr0, %eax")
- * ENABLE_INTERRUPTS_SYSEXIT (aka "sti; sysexit").
- *
- * For DISABLE_INTERRUPTS/ENABLE_INTERRUPTS (aka "cli"/"sti"), you must
- * specify what registers can be overwritten (CLBR_NONE, CLBR_EAX/EDX/ECX/ANY).
- * Allowing a register to be clobbered can shrink the paravirt replacement
- * enough to patch inline, increasing performance.
- */
-
-#define nr_syscalls ((syscall_table_size)/4)
-
-CF_MASK = 0x00000001
-TF_MASK = 0x00000100
-IF_MASK = 0x00000200
-DF_MASK = 0x00000400
-NT_MASK = 0x00004000
-VM_MASK = 0x00020000
-
-#ifdef CONFIG_PREEMPT
-#define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF
-#else
-#define preempt_stop(clobbers)
-#define resume_kernel restore_nocheck
-#endif
-
-.macro TRACE_IRQS_IRET
-#ifdef CONFIG_TRACE_IRQFLAGS
- testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off?
- jz 1f
- TRACE_IRQS_ON
-1:
-#endif
-.endm
-
-#ifdef CONFIG_VM86
-#define resume_userspace_sig check_userspace
-#else
-#define resume_userspace_sig resume_userspace
-#endif
-
-#define SAVE_ALL \
- cld; \
- pushl %fs; \
- CFI_ADJUST_CFA_OFFSET 4;\
- /*CFI_REL_OFFSET fs, 0;*/\
- pushl %es; \
- CFI_ADJUST_CFA_OFFSET 4;\
- /*CFI_REL_OFFSET es, 0;*/\
- pushl %ds; \
- CFI_ADJUST_CFA_OFFSET 4;\
- /*CFI_REL_OFFSET ds, 0;*/\
- pushl %eax; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET eax, 0;\
- pushl %ebp; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET ebp, 0;\
- pushl %edi; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET edi, 0;\
- pushl %esi; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET esi, 0;\
- pushl %edx; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET edx, 0;\
- pushl %ecx; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET ecx, 0;\
- pushl %ebx; \
- CFI_ADJUST_CFA_OFFSET 4;\
- CFI_REL_OFFSET ebx, 0;\
- movl $(__USER_DS), %edx; \
- movl %edx, %ds; \
- movl %edx, %es; \
- movl $(__KERNEL_PERCPU), %edx; \
- movl %edx, %fs
-
-#define RESTORE_INT_REGS \
- popl %ebx; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE ebx;\
- popl %ecx; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE ecx;\
- popl %edx; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE edx;\
- popl %esi; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE esi;\
- popl %edi; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE edi;\
- popl %ebp; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE ebp;\
- popl %eax; \
- CFI_ADJUST_CFA_OFFSET -4;\
- CFI_RESTORE eax
-
-#define RESTORE_REGS \
- RESTORE_INT_REGS; \
-1: popl %ds; \
- CFI_ADJUST_CFA_OFFSET -4;\
- /*CFI_RESTORE ds;*/\
-2: popl %es; \
- CFI_ADJUST_CFA_OFFSET -4;\
- /*CFI_RESTORE es;*/\
-3: popl %fs; \
- CFI_ADJUST_CFA_OFFSET -4;\
- /*CFI_RESTORE fs;*/\
-.pushsection .fixup,"ax"; \
-4: movl $0,(%esp); \
- jmp 1b; \
-5: movl $0,(%esp); \
- jmp 2b; \
-6: movl $0,(%esp); \
- jmp 3b; \
-.section __ex_table,"a";\
- .align 4; \
- .long 1b,4b; \
- .long 2b,5b; \
- .long 3b,6b; \
-.popsection
-
-#define RING0_INT_FRAME \
- CFI_STARTPROC simple;\
- CFI_SIGNAL_FRAME;\
- CFI_DEF_CFA esp, 3*4;\
- /*CFI_OFFSET cs, -2*4;*/\
- CFI_OFFSET eip, -3*4
-
-#define RING0_EC_FRAME \
- CFI_STARTPROC simple;\
- CFI_SIGNAL_FRAME;\
- CFI_DEF_CFA esp, 4*4;\
- /*CFI_OFFSET cs, -2*4;*/\
- CFI_OFFSET eip, -3*4
-
-#define RING0_PTREGS_FRAME \
- CFI_STARTPROC simple;\
- CFI_SIGNAL_FRAME;\
- CFI_DEF_CFA esp, PT_OLDESP-PT_EBX;\
- /*CFI_OFFSET cs, PT_CS-PT_OLDESP;*/\
- CFI_OFFSET eip, PT_EIP-PT_OLDESP;\
- /*CFI_OFFSET es, PT_ES-PT_OLDESP;*/\
- /*CFI_OFFSET ds, PT_DS-PT_OLDESP;*/\
- CFI_OFFSET eax, PT_EAX-PT_OLDESP;\
- CFI_OFFSET ebp, PT_EBP-PT_OLDESP;\
- CFI_OFFSET edi, PT_EDI-PT_OLDESP;\
- CFI_OFFSET esi, PT_ESI-PT_OLDESP;\
- CFI_OFFSET edx, PT_EDX-PT_OLDESP;\
- CFI_OFFSET ecx, PT_ECX-PT_OLDESP;\
- CFI_OFFSET ebx, PT_EBX-PT_OLDESP
-
-ENTRY(ret_from_fork)
- CFI_STARTPROC
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- call schedule_tail
- GET_THREAD_INFO(%ebp)
- popl %eax
- CFI_ADJUST_CFA_OFFSET -4
- pushl $0x0202 # Reset kernel eflags
- CFI_ADJUST_CFA_OFFSET 4
- popfl
- CFI_ADJUST_CFA_OFFSET -4
- jmp syscall_exit
- CFI_ENDPROC
-END(ret_from_fork)
-
-/*
- * Return to user mode is not as complex as all this looks,
- * but we want the default path for a system call return to
- * go as quickly as possible which is why some of this is
- * less clear than it otherwise should be.
- */
-
- # userspace resumption stub bypassing syscall exit tracing
- ALIGN
- RING0_PTREGS_FRAME
-ret_from_exception:
- preempt_stop(CLBR_ANY)
-ret_from_intr:
- GET_THREAD_INFO(%ebp)
-check_userspace:
- movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS
- movb PT_CS(%esp), %al
- andl $(VM_MASK | SEGMENT_RPL_MASK), %eax
- cmpl $USER_RPL, %eax
- jb resume_kernel # not returning to v8086 or userspace
-
-ENTRY(resume_userspace)
- DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
- # setting need_resched or sigpending
- # between sampling and the iret
- movl TI_flags(%ebp), %ecx
- andl $_TIF_WORK_MASK, %ecx # is there any work to be done on
- # int/exception return?
- jne work_pending
- jmp restore_all
-END(ret_from_exception)
-
-#ifdef CONFIG_PREEMPT
-ENTRY(resume_kernel)
- DISABLE_INTERRUPTS(CLBR_ANY)
- cmpl $0,TI_preempt_count(%ebp) # non-zero preempt_count ?
- jnz restore_nocheck
-need_resched:
- movl TI_flags(%ebp), %ecx # need_resched set ?
- testb $_TIF_NEED_RESCHED, %cl
- jz restore_all
- testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off (exception path) ?
- jz restore_all
- call preempt_schedule_irq
- jmp need_resched
-END(resume_kernel)
-#endif
- CFI_ENDPROC
-
-/* SYSENTER_RETURN points to after the "sysenter" instruction in
- the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
-
- # sysenter call handler stub
-ENTRY(sysenter_entry)
- CFI_STARTPROC simple
- CFI_SIGNAL_FRAME
- CFI_DEF_CFA esp, 0
- CFI_REGISTER esp, ebp
- movl TSS_sysenter_esp0(%esp),%esp
-sysenter_past_esp:
- /*
- * No need to follow this irqs on/off section: the syscall
- * disabled irqs and here we enable it straight after entry:
- */
- ENABLE_INTERRUPTS(CLBR_NONE)
- pushl $(__USER_DS)
- CFI_ADJUST_CFA_OFFSET 4
- /*CFI_REL_OFFSET ss, 0*/
- pushl %ebp
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET esp, 0
- pushfl
- CFI_ADJUST_CFA_OFFSET 4
- pushl $(__USER_CS)
- CFI_ADJUST_CFA_OFFSET 4
- /*CFI_REL_OFFSET cs, 0*/
- /*
- * Push current_thread_info()->sysenter_return to the stack.
- * A tiny bit of offset fixup is necessary - 4*4 means the 4 words
- * pushed above; +8 corresponds to copy_thread's esp0 setting.
- */
- pushl (TI_sysenter_return-THREAD_SIZE+8+4*4)(%esp)
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET eip, 0
-
-/*
- * Load the potential sixth argument from user stack.
- * Careful about security.
- */
- cmpl $__PAGE_OFFSET-3,%ebp
- jae syscall_fault
-1: movl (%ebp),%ebp
-.section __ex_table,"a"
- .align 4
- .long 1b,syscall_fault
-.previous
-
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- GET_THREAD_INFO(%ebp)
-
- /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
- testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
- jnz syscall_trace_entry
- cmpl $(nr_syscalls), %eax
- jae syscall_badsys
- call *sys_call_table(,%eax,4)
- movl %eax,PT_EAX(%esp)
- DISABLE_INTERRUPTS(CLBR_ANY)
- TRACE_IRQS_OFF
- movl TI_flags(%ebp), %ecx
- testw $_TIF_ALLWORK_MASK, %cx
- jne syscall_exit_work
-/* 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
- ENABLE_INTERRUPTS_SYSEXIT
- CFI_ENDPROC
-.pushsection .fixup,"ax"
-2: movl $0,PT_FS(%esp)
- jmp 1b
-.section __ex_table,"a"
- .align 4
- .long 1b,2b
-.popsection
-ENDPROC(sysenter_entry)
-
- # system call handler stub
-ENTRY(system_call)
- RING0_INT_FRAME # can't unwind into user space anyway
- pushl %eax # save orig_eax
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- GET_THREAD_INFO(%ebp)
- # system call tracing in operation / emulation
- /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
- testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
- jnz syscall_trace_entry
- cmpl $(nr_syscalls), %eax
- jae syscall_badsys
-syscall_call:
- call *sys_call_table(,%eax,4)
- movl %eax,PT_EAX(%esp) # store the return value
-syscall_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
- testl $TF_MASK,PT_EFLAGS(%esp) # If tracing set singlestep flag on exit
- jz no_singlestep
- orl $_TIF_SINGLESTEP,TI_flags(%ebp)
-no_singlestep:
- movl TI_flags(%ebp), %ecx
- testw $_TIF_ALLWORK_MASK, %cx # current->work
- jne syscall_exit_work
-
-restore_all:
- 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 $(VM_MASK | (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
-restore_nocheck:
- TRACE_IRQS_IRET
-restore_nocheck_notrace:
- RESTORE_REGS
- addl $4, %esp # skip orig_eax/error_code
- CFI_ADJUST_CFA_OFFSET -4
-1: INTERRUPT_RETURN
-.section .fixup,"ax"
-iret_exc:
- pushl $0 # no error code
- pushl $do_iret_error
- jmp error_code
-.previous
-.section __ex_table,"a"
- .align 4
- .long 1b,iret_exc
-.previous
-
- CFI_RESTORE_STATE
-ldt_ss:
- larl PT_OLDSS(%esp), %eax
- jnz restore_nocheck
- testl $0x00400000, %eax # returning to 32bit stack?
- jnz restore_nocheck # allright, normal return
-
-#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, paravirt_ops+PARAVIRT_enabled
- jne restore_nocheck
-#endif
-
- /* If returning to userspace with 16bit stack,
- * try to fix the higher word of ESP, as the CPU
- * won't restore it.
- * This is an "official" bug of all the x86-compatible
- * CPUs, which we can try to work around to make
- * dosemu and wine happy. */
- movl PT_OLDESP(%esp), %eax
- movl %esp, %edx
- call patch_espfix_desc
- pushl $__ESPFIX_SS
- CFI_ADJUST_CFA_OFFSET 4
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- DISABLE_INTERRUPTS(CLBR_EAX)
- TRACE_IRQS_OFF
- lss (%esp), %esp
- CFI_ADJUST_CFA_OFFSET -8
- jmp restore_nocheck
- 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
- 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 $VM_MASK, PT_EFLAGS(%esp)
- movl %esp, %eax
- jne work_notifysig_v86 # returning to kernel-space or
- # vm86-space
- xorl %edx, %edx
- call do_notify_resume
- jmp resume_userspace_sig
-
- ALIGN
-work_notifysig_v86:
- pushl %ecx # save ti_flags for do_notify_resume
- CFI_ADJUST_CFA_OFFSET 4
- call save_v86_state # %eax contains pt_regs pointer
- popl %ecx
- CFI_ADJUST_CFA_OFFSET -4
- movl %eax, %esp
-#else
- movl %esp, %eax
-#endif
- xorl %edx, %edx
- call do_notify_resume
- jmp resume_userspace_sig
-END(work_pending)
-
- # perform syscall exit tracing
- ALIGN
-syscall_trace_entry:
- movl $-ENOSYS,PT_EAX(%esp)
- movl %esp, %eax
- xorl %edx,%edx
- call do_syscall_trace
- cmpl $0, %eax
- jne resume_userspace # ret != 0 -> running under PTRACE_SYSEMU,
- # so must skip actual syscall
- movl PT_ORIG_EAX(%esp), %eax
- cmpl $(nr_syscalls), %eax
- jnae syscall_call
- jmp syscall_exit
-END(syscall_trace_entry)
-
- # perform syscall exit tracing
- ALIGN
-syscall_exit_work:
- testb $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP), %cl
- jz work_pending
- TRACE_IRQS_ON
- ENABLE_INTERRUPTS(CLBR_ANY) # could let do_syscall_trace() call
- # schedule() instead
- movl %esp, %eax
- movl $1, %edx
- call do_syscall_trace
- jmp resume_userspace
-END(syscall_exit_work)
- CFI_ENDPROC
-
- RING0_INT_FRAME # can't unwind into user space anyway
-syscall_fault:
- pushl %eax # save orig_eax
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- GET_THREAD_INFO(%ebp)
- movl $-EFAULT,PT_EAX(%esp)
- jmp resume_userspace
-END(syscall_fault)
-
-syscall_badsys:
- movl $-ENOSYS,PT_EAX(%esp)
- jmp resume_userspace
-END(syscall_badsys)
- CFI_ENDPROC
-
-#define FIXUP_ESPFIX_STACK \
- /* since we are on a wrong stack, we cant make it a C code :( */ \
- PER_CPU(gdt_page, %ebx); \
- GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \
- addl %esp, %eax; \
- pushl $__KERNEL_DS; \
- CFI_ADJUST_CFA_OFFSET 4; \
- pushl %eax; \
- CFI_ADJUST_CFA_OFFSET 4; \
- lss (%esp), %esp; \
- CFI_ADJUST_CFA_OFFSET -8;
-#define UNWIND_ESPFIX_STACK \
- 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:;
-
-/*
- * Build the entry stubs and pointer table with
- * some assembler magic.
- */
-.data
-ENTRY(interrupt)
-.text
-
-ENTRY(irq_entries_start)
- RING0_INT_FRAME
-vector=0
-.rept NR_IRQS
- ALIGN
- .if vector
- CFI_ADJUST_CFA_OFFSET -4
- .endif
-1: pushl $~(vector)
- CFI_ADJUST_CFA_OFFSET 4
- jmp common_interrupt
- .previous
- .long 1b
- .text
-vector=vector+1
-.endr
-END(irq_entries_start)
-
-.previous
-END(interrupt)
-.previous
-
-/*
- * the CPU automatically disables interrupts when executing an IRQ vector,
- * so IRQ-flags tracing has to follow that:
- */
- ALIGN
-common_interrupt:
- SAVE_ALL
- TRACE_IRQS_OFF
- movl %esp,%eax
- call do_IRQ
- jmp ret_from_intr
-ENDPROC(common_interrupt)
- CFI_ENDPROC
-
-#define BUILD_INTERRUPT(name, nr) \
-ENTRY(name) \
- RING0_INT_FRAME; \
- pushl $~(nr); \
- CFI_ADJUST_CFA_OFFSET 4; \
- SAVE_ALL; \
- TRACE_IRQS_OFF \
- movl %esp,%eax; \
- call smp_##name; \
- jmp ret_from_intr; \
- CFI_ENDPROC; \
-ENDPROC(name)
-
-/* The include is where all of the SMP etc. interrupts come from */
-#include "entry_arch.h"
-
-KPROBE_ENTRY(page_fault)
- RING0_EC_FRAME
- pushl $do_page_fault
- CFI_ADJUST_CFA_OFFSET 4
- ALIGN
-error_code:
- /* the function address is in %fs's slot on the stack */
- pushl %es
- CFI_ADJUST_CFA_OFFSET 4
- /*CFI_REL_OFFSET es, 0*/
- pushl %ds
- CFI_ADJUST_CFA_OFFSET 4
- /*CFI_REL_OFFSET ds, 0*/
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET eax, 0
- pushl %ebp
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET ebp, 0
- pushl %edi
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET edi, 0
- pushl %esi
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET esi, 0
- pushl %edx
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET edx, 0
- pushl %ecx
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET ecx, 0
- pushl %ebx
- CFI_ADJUST_CFA_OFFSET 4
- CFI_REL_OFFSET ebx, 0
- cld
- pushl %fs
- CFI_ADJUST_CFA_OFFSET 4
- /*CFI_REL_OFFSET fs, 0*/
- movl $(__KERNEL_PERCPU), %ecx
- movl %ecx, %fs
- UNWIND_ESPFIX_STACK
- popl %ecx
- CFI_ADJUST_CFA_OFFSET -4
- /*CFI_REGISTER es, ecx*/
- movl PT_FS(%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
- mov %ecx, PT_FS(%esp)
- /*CFI_REL_OFFSET fs, ES*/
- movl $(__USER_DS), %ecx
- movl %ecx, %ds
- movl %ecx, %es
- movl %esp,%eax # pt_regs pointer
- call *%edi
- jmp ret_from_exception
- CFI_ENDPROC
-KPROBE_END(page_fault)
-
-ENTRY(coprocessor_error)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_coprocessor_error
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(coprocessor_error)
-
-ENTRY(simd_coprocessor_error)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_simd_coprocessor_error
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(simd_coprocessor_error)
-
-ENTRY(device_not_available)
- RING0_INT_FRAME
- pushl $-1 # mark this as an int
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- GET_CR0_INTO_EAX
- testl $0x4, %eax # EM (math emulation bit)
- jne device_not_available_emulate
- preempt_stop(CLBR_ANY)
- call math_state_restore
- jmp ret_from_exception
-device_not_available_emulate:
- pushl $0 # temporary storage for ORIG_EIP
- CFI_ADJUST_CFA_OFFSET 4
- call math_emulate
- addl $4, %esp
- CFI_ADJUST_CFA_OFFSET -4
- jmp ret_from_exception
- CFI_ENDPROC
-END(device_not_available)
-
-/*
- * 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_esp0+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.
- */
-#define FIX_STACK(offset, ok, label) \
- cmpw $__KERNEL_CS,4(%esp); \
- jne ok; \
-label: \
- movl TSS_sysenter_esp0+offset(%esp),%esp; \
- CFI_DEF_CFA esp, 0; \
- CFI_UNDEFINED eip; \
- pushfl; \
- CFI_ADJUST_CFA_OFFSET 4; \
- pushl $__KERNEL_CS; \
- CFI_ADJUST_CFA_OFFSET 4; \
- pushl $sysenter_past_esp; \
- CFI_ADJUST_CFA_OFFSET 4; \
- CFI_REL_OFFSET eip, 0
-
-KPROBE_ENTRY(debug)
- RING0_INT_FRAME
- cmpl $sysenter_entry,(%esp)
- jne debug_stack_correct
- FIX_STACK(12, debug_stack_correct, debug_esp_fix_insn)
-debug_stack_correct:
- pushl $-1 # mark this as an int
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- xorl %edx,%edx # error code 0
- movl %esp,%eax # pt_regs pointer
- call do_debug
- jmp ret_from_exception
- CFI_ENDPROC
-KPROBE_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.
- */
-KPROBE_ENTRY(nmi)
- RING0_INT_FRAME
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- movl %ss, %eax
- cmpw $__ESPFIX_SS, %ax
- popl %eax
- CFI_ADJUST_CFA_OFFSET -4
- je nmi_espfix_stack
- cmpl $sysenter_entry,(%esp)
- je nmi_stack_fixup
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- 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 %eax
- CFI_ADJUST_CFA_OFFSET -4
- jae nmi_stack_correct
- cmpl $sysenter_entry,12(%esp)
- je nmi_debug_stack_check
-nmi_stack_correct:
- /* We have a RING0_INT_FRAME here */
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- xorl %edx,%edx # zero error code
- movl %esp,%eax # pt_regs pointer
- call do_nmi
- jmp restore_nocheck_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
-
-nmi_espfix_stack:
- /* We have a RING0_INT_FRAME here.
- *
- * create the pointer to lss back
- */
- pushl %ss
- CFI_ADJUST_CFA_OFFSET 4
- pushl %esp
- CFI_ADJUST_CFA_OFFSET 4
- addw $4, (%esp)
- /* copy the iret frame of 12 bytes */
- .rept 3
- pushl 16(%esp)
- CFI_ADJUST_CFA_OFFSET 4
- .endr
- pushl %eax
- CFI_ADJUST_CFA_OFFSET 4
- 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
-1: INTERRUPT_RETURN
- CFI_ENDPROC
-.section __ex_table,"a"
- .align 4
- .long 1b,iret_exc
-.previous
-KPROBE_END(nmi)
-
-#ifdef CONFIG_PARAVIRT
-ENTRY(native_iret)
-1: iret
-.section __ex_table,"a"
- .align 4
- .long 1b,iret_exc
-.previous
-END(native_iret)
-
-ENTRY(native_irq_enable_sysexit)
- sti
- sysexit
-END(native_irq_enable_sysexit)
-#endif
-
-KPROBE_ENTRY(int3)
- RING0_INT_FRAME
- pushl $-1 # mark this as an int
- CFI_ADJUST_CFA_OFFSET 4
- SAVE_ALL
- xorl %edx,%edx # zero error code
- movl %esp,%eax # pt_regs pointer
- call do_int3
- jmp ret_from_exception
- CFI_ENDPROC
-KPROBE_END(int3)
-
-ENTRY(overflow)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_overflow
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(overflow)
-
-ENTRY(bounds)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_bounds
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(bounds)
-
-ENTRY(invalid_op)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_invalid_op
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(invalid_op)
-
-ENTRY(coprocessor_segment_overrun)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_coprocessor_segment_overrun
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(coprocessor_segment_overrun)
-
-ENTRY(invalid_TSS)
- RING0_EC_FRAME
- pushl $do_invalid_TSS
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(invalid_TSS)
-
-ENTRY(segment_not_present)
- RING0_EC_FRAME
- pushl $do_segment_not_present
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(segment_not_present)
-
-ENTRY(stack_segment)
- RING0_EC_FRAME
- pushl $do_stack_segment
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(stack_segment)
-
-KPROBE_ENTRY(general_protection)
- RING0_EC_FRAME
- pushl $do_general_protection
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-KPROBE_END(general_protection)
-
-ENTRY(alignment_check)
- RING0_EC_FRAME
- pushl $do_alignment_check
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(alignment_check)
-
-ENTRY(divide_error)
- RING0_INT_FRAME
- pushl $0 # no error code
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_divide_error
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(divide_error)
-
-#ifdef CONFIG_X86_MCE
-ENTRY(machine_check)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl machine_check_vector
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(machine_check)
-#endif
-
-ENTRY(spurious_interrupt_bug)
- RING0_INT_FRAME
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- pushl $do_spurious_interrupt_bug
- CFI_ADJUST_CFA_OFFSET 4
- jmp error_code
- CFI_ENDPROC
-END(spurious_interrupt_bug)
-
-ENTRY(kernel_thread_helper)
- pushl $0 # fake return address for unwinder
- CFI_STARTPROC
- movl %edx,%eax
- push %edx
- CFI_ADJUST_CFA_OFFSET 4
- call *%ebx
- push %eax
- CFI_ADJUST_CFA_OFFSET 4
- call do_exit
- CFI_ENDPROC
-ENDPROC(kernel_thread_helper)
-
-#ifdef CONFIG_XEN
-ENTRY(xen_hypervisor_callback)
- CFI_STARTPROC
- pushl $0
- CFI_ADJUST_CFA_OFFSET 4
- 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
-
- call xen_iret_crit_fixup
-
-1: mov %esp, %eax
- call xen_evtchn_do_upcall
- 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 %eax
- CFI_ADJUST_CFA_OFFSET 4
- movl $1,%eax
-1: mov 4(%esp),%ds
-2: mov 8(%esp),%es
-3: mov 12(%esp),%fs
-4: mov 16(%esp),%gs
- testl %eax,%eax
- popl %eax
- CFI_ADJUST_CFA_OFFSET -4
- lea 16(%esp),%esp
- CFI_ADJUST_CFA_OFFSET -16
- jz 5f
- addl $16,%esp
- jmp iret_exc # EAX != 0 => Category 2 (Bad IRET)
-5: pushl $0 # EAX == 0 => Category 1 (Bad segment)
- CFI_ADJUST_CFA_OFFSET 4
- 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
-.section __ex_table,"a"
- .align 4
- .long 1b,6b
- .long 2b,7b
- .long 3b,8b
- .long 4b,9b
-.previous
-ENDPROC(xen_failsafe_callback)
-
-#endif /* CONFIG_XEN */
-
-.section .rodata,"a"
-#include "syscall_table_32.S"
-
-syscall_table_size=(.-sys_call_table)
--- /dev/null
+/*
+ * linux/arch/i386/entry.S
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+/*
+ * entry.S contains the system-call and fault low-level handling routines.
+ * This also contains the timer-interrupt handler, as well as all interrupts
+ * and faults that can result in a task-switch.
+ *
+ * NOTE: This code handles signal-recognition, which happens every time
+ * after a timer-interrupt and after each system call.
+ *
+ * I changed all the .align's to 4 (16 byte alignment), as that's faster
+ * on a 486.
+ *
+ * Stack layout in 'syscall_exit':
+ * ptrace needs to have all regs on the stack.
+ * if the order here is changed, it needs to be
+ * updated in fork.c:copy_process, signal.c:do_signal,
+ * ptrace.c and ptrace.h
+ *
+ * 0(%esp) - %ebx
+ * 4(%esp) - %ecx
+ * 8(%esp) - %edx
+ * C(%esp) - %esi
+ * 10(%esp) - %edi
+ * 14(%esp) - %ebp
+ * 18(%esp) - %eax
+ * 1C(%esp) - %ds
+ * 20(%esp) - %es
+ * 24(%esp) - %fs
+ * 28(%esp) - orig_eax
+ * 2C(%esp) - %eip
+ * 30(%esp) - %cs
+ * 34(%esp) - %eflags
+ * 38(%esp) - %oldesp
+ * 3C(%esp) - %oldss
+ *
+ * "current" is in register %ebx during any slow entries.
+ */
+
+#include <linux/linkage.h>
+#include <asm/thread_info.h>
+#include <asm/irqflags.h>
+#include <asm/errno.h>
+#include <asm/segment.h>
+#include <asm/smp.h>
+#include <asm/page.h>
+#include <asm/desc.h>
+#include <asm/percpu.h>
+#include <asm/dwarf2.h>
+#include "irq_vectors.h"
+
+/*
+ * We use macros for low-level operations which need to be overridden
+ * for paravirtualization. The following will never clobber any registers:
+ * INTERRUPT_RETURN (aka. "iret")
+ * GET_CR0_INTO_EAX (aka. "movl %cr0, %eax")
+ * ENABLE_INTERRUPTS_SYSEXIT (aka "sti; sysexit").
+ *
+ * For DISABLE_INTERRUPTS/ENABLE_INTERRUPTS (aka "cli"/"sti"), you must
+ * specify what registers can be overwritten (CLBR_NONE, CLBR_EAX/EDX/ECX/ANY).
+ * Allowing a register to be clobbered can shrink the paravirt replacement
+ * enough to patch inline, increasing performance.
+ */
+
+#define nr_syscalls ((syscall_table_size)/4)
+
+CF_MASK = 0x00000001
+TF_MASK = 0x00000100
+IF_MASK = 0x00000200
+DF_MASK = 0x00000400
+NT_MASK = 0x00004000
+VM_MASK = 0x00020000
+
+#ifdef CONFIG_PREEMPT
+#define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF
+#else
+#define preempt_stop(clobbers)
+#define resume_kernel restore_nocheck
+#endif
+
+.macro TRACE_IRQS_IRET
+#ifdef CONFIG_TRACE_IRQFLAGS
+ testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off?
+ jz 1f
+ TRACE_IRQS_ON
+1:
+#endif
+.endm
+
+#ifdef CONFIG_VM86
+#define resume_userspace_sig check_userspace
+#else
+#define resume_userspace_sig resume_userspace
+#endif
+
+#define SAVE_ALL \
+ cld; \
+ pushl %fs; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ /*CFI_REL_OFFSET fs, 0;*/\
+ pushl %es; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ /*CFI_REL_OFFSET es, 0;*/\
+ pushl %ds; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ /*CFI_REL_OFFSET ds, 0;*/\
+ pushl %eax; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET eax, 0;\
+ pushl %ebp; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET ebp, 0;\
+ pushl %edi; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET edi, 0;\
+ pushl %esi; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET esi, 0;\
+ pushl %edx; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET edx, 0;\
+ pushl %ecx; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET ecx, 0;\
+ pushl %ebx; \
+ CFI_ADJUST_CFA_OFFSET 4;\
+ CFI_REL_OFFSET ebx, 0;\
+ movl $(__USER_DS), %edx; \
+ movl %edx, %ds; \
+ movl %edx, %es; \
+ movl $(__KERNEL_PERCPU), %edx; \
+ movl %edx, %fs
+
+#define RESTORE_INT_REGS \
+ popl %ebx; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE ebx;\
+ popl %ecx; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE ecx;\
+ popl %edx; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE edx;\
+ popl %esi; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE esi;\
+ popl %edi; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE edi;\
+ popl %ebp; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE ebp;\
+ popl %eax; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ CFI_RESTORE eax
+
+#define RESTORE_REGS \
+ RESTORE_INT_REGS; \
+1: popl %ds; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ /*CFI_RESTORE ds;*/\
+2: popl %es; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ /*CFI_RESTORE es;*/\
+3: popl %fs; \
+ CFI_ADJUST_CFA_OFFSET -4;\
+ /*CFI_RESTORE fs;*/\
+.pushsection .fixup,"ax"; \
+4: movl $0,(%esp); \
+ jmp 1b; \
+5: movl $0,(%esp); \
+ jmp 2b; \
+6: movl $0,(%esp); \
+ jmp 3b; \
+.section __ex_table,"a";\
+ .align 4; \
+ .long 1b,4b; \
+ .long 2b,5b; \
+ .long 3b,6b; \
+.popsection
+
+#define RING0_INT_FRAME \
+ CFI_STARTPROC simple;\
+ CFI_SIGNAL_FRAME;\
+ CFI_DEF_CFA esp, 3*4;\
+ /*CFI_OFFSET cs, -2*4;*/\
+ CFI_OFFSET eip, -3*4
+
+#define RING0_EC_FRAME \
+ CFI_STARTPROC simple;\
+ CFI_SIGNAL_FRAME;\
+ CFI_DEF_CFA esp, 4*4;\
+ /*CFI_OFFSET cs, -2*4;*/\
+ CFI_OFFSET eip, -3*4
+
+#define RING0_PTREGS_FRAME \
+ CFI_STARTPROC simple;\
+ CFI_SIGNAL_FRAME;\
+ CFI_DEF_CFA esp, PT_OLDESP-PT_EBX;\
+ /*CFI_OFFSET cs, PT_CS-PT_OLDESP;*/\
+ CFI_OFFSET eip, PT_EIP-PT_OLDESP;\
+ /*CFI_OFFSET es, PT_ES-PT_OLDESP;*/\
+ /*CFI_OFFSET ds, PT_DS-PT_OLDESP;*/\
+ CFI_OFFSET eax, PT_EAX-PT_OLDESP;\
+ CFI_OFFSET ebp, PT_EBP-PT_OLDESP;\
+ CFI_OFFSET edi, PT_EDI-PT_OLDESP;\
+ CFI_OFFSET esi, PT_ESI-PT_OLDESP;\
+ CFI_OFFSET edx, PT_EDX-PT_OLDESP;\
+ CFI_OFFSET ecx, PT_ECX-PT_OLDESP;\
+ CFI_OFFSET ebx, PT_EBX-PT_OLDESP
+
+ENTRY(ret_from_fork)
+ CFI_STARTPROC
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ call schedule_tail
+ GET_THREAD_INFO(%ebp)
+ popl %eax
+ CFI_ADJUST_CFA_OFFSET -4
+ pushl $0x0202 # Reset kernel eflags
+ CFI_ADJUST_CFA_OFFSET 4
+ popfl
+ CFI_ADJUST_CFA_OFFSET -4
+ jmp syscall_exit
+ CFI_ENDPROC
+END(ret_from_fork)
+
+/*
+ * Return to user mode is not as complex as all this looks,
+ * but we want the default path for a system call return to
+ * go as quickly as possible which is why some of this is
+ * less clear than it otherwise should be.
+ */
+
+ # userspace resumption stub bypassing syscall exit tracing
+ ALIGN
+ RING0_PTREGS_FRAME
+ret_from_exception:
+ preempt_stop(CLBR_ANY)
+ret_from_intr:
+ GET_THREAD_INFO(%ebp)
+check_userspace:
+ movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS
+ movb PT_CS(%esp), %al
+ andl $(VM_MASK | SEGMENT_RPL_MASK), %eax
+ cmpl $USER_RPL, %eax
+ jb resume_kernel # not returning to v8086 or userspace
+
+ENTRY(resume_userspace)
+ DISABLE_INTERRUPTS(CLBR_ANY) # make sure we don't miss an interrupt
+ # setting need_resched or sigpending
+ # between sampling and the iret
+ movl TI_flags(%ebp), %ecx
+ andl $_TIF_WORK_MASK, %ecx # is there any work to be done on
+ # int/exception return?
+ jne work_pending
+ jmp restore_all
+END(ret_from_exception)
+
+#ifdef CONFIG_PREEMPT
+ENTRY(resume_kernel)
+ DISABLE_INTERRUPTS(CLBR_ANY)
+ cmpl $0,TI_preempt_count(%ebp) # non-zero preempt_count ?
+ jnz restore_nocheck
+need_resched:
+ movl TI_flags(%ebp), %ecx # need_resched set ?
+ testb $_TIF_NEED_RESCHED, %cl
+ jz restore_all
+ testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off (exception path) ?
+ jz restore_all
+ call preempt_schedule_irq
+ jmp need_resched
+END(resume_kernel)
+#endif
+ CFI_ENDPROC
+
+/* SYSENTER_RETURN points to after the "sysenter" instruction in
+ the vsyscall page. See vsyscall-sysentry.S, which defines the symbol. */
+
+ # sysenter call handler stub
+ENTRY(sysenter_entry)
+ CFI_STARTPROC simple
+ CFI_SIGNAL_FRAME
+ CFI_DEF_CFA esp, 0
+ CFI_REGISTER esp, ebp
+ movl TSS_sysenter_esp0(%esp),%esp
+sysenter_past_esp:
+ /*
+ * No need to follow this irqs on/off section: the syscall
+ * disabled irqs and here we enable it straight after entry:
+ */
+ ENABLE_INTERRUPTS(CLBR_NONE)
+ pushl $(__USER_DS)
+ CFI_ADJUST_CFA_OFFSET 4
+ /*CFI_REL_OFFSET ss, 0*/
+ pushl %ebp
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET esp, 0
+ pushfl
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $(__USER_CS)
+ CFI_ADJUST_CFA_OFFSET 4
+ /*CFI_REL_OFFSET cs, 0*/
+ /*
+ * Push current_thread_info()->sysenter_return to the stack.
+ * A tiny bit of offset fixup is necessary - 4*4 means the 4 words
+ * pushed above; +8 corresponds to copy_thread's esp0 setting.
+ */
+ pushl (TI_sysenter_return-THREAD_SIZE+8+4*4)(%esp)
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET eip, 0
+
+/*
+ * Load the potential sixth argument from user stack.
+ * Careful about security.
+ */
+ cmpl $__PAGE_OFFSET-3,%ebp
+ jae syscall_fault
+1: movl (%ebp),%ebp
+.section __ex_table,"a"
+ .align 4
+ .long 1b,syscall_fault
+.previous
+
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ GET_THREAD_INFO(%ebp)
+
+ /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
+ testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
+ jnz syscall_trace_entry
+ cmpl $(nr_syscalls), %eax
+ jae syscall_badsys
+ call *sys_call_table(,%eax,4)
+ movl %eax,PT_EAX(%esp)
+ DISABLE_INTERRUPTS(CLBR_ANY)
+ TRACE_IRQS_OFF
+ movl TI_flags(%ebp), %ecx
+ testw $_TIF_ALLWORK_MASK, %cx
+ jne syscall_exit_work
+/* 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
+ ENABLE_INTERRUPTS_SYSEXIT
+ CFI_ENDPROC
+.pushsection .fixup,"ax"
+2: movl $0,PT_FS(%esp)
+ jmp 1b
+.section __ex_table,"a"
+ .align 4
+ .long 1b,2b
+.popsection
+ENDPROC(sysenter_entry)
+
+ # system call handler stub
+ENTRY(system_call)
+ RING0_INT_FRAME # can't unwind into user space anyway
+ pushl %eax # save orig_eax
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ GET_THREAD_INFO(%ebp)
+ # system call tracing in operation / emulation
+ /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */
+ testw $(_TIF_SYSCALL_EMU|_TIF_SYSCALL_TRACE|_TIF_SECCOMP|_TIF_SYSCALL_AUDIT),TI_flags(%ebp)
+ jnz syscall_trace_entry
+ cmpl $(nr_syscalls), %eax
+ jae syscall_badsys
+syscall_call:
+ call *sys_call_table(,%eax,4)
+ movl %eax,PT_EAX(%esp) # store the return value
+syscall_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
+ testl $TF_MASK,PT_EFLAGS(%esp) # If tracing set singlestep flag on exit
+ jz no_singlestep
+ orl $_TIF_SINGLESTEP,TI_flags(%ebp)
+no_singlestep:
+ movl TI_flags(%ebp), %ecx
+ testw $_TIF_ALLWORK_MASK, %cx # current->work
+ jne syscall_exit_work
+
+restore_all:
+ 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 $(VM_MASK | (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
+restore_nocheck:
+ TRACE_IRQS_IRET
+restore_nocheck_notrace:
+ RESTORE_REGS
+ addl $4, %esp # skip orig_eax/error_code
+ CFI_ADJUST_CFA_OFFSET -4
+1: INTERRUPT_RETURN
+.section .fixup,"ax"
+iret_exc:
+ pushl $0 # no error code
+ pushl $do_iret_error
+ jmp error_code
+.previous
+.section __ex_table,"a"
+ .align 4
+ .long 1b,iret_exc
+.previous
+
+ CFI_RESTORE_STATE
+ldt_ss:
+ larl PT_OLDSS(%esp), %eax
+ jnz restore_nocheck
+ testl $0x00400000, %eax # returning to 32bit stack?
+ jnz restore_nocheck # allright, normal return
+
+#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, paravirt_ops+PARAVIRT_enabled
+ jne restore_nocheck
+#endif
+
+ /* If returning to userspace with 16bit stack,
+ * try to fix the higher word of ESP, as the CPU
+ * won't restore it.
+ * This is an "official" bug of all the x86-compatible
+ * CPUs, which we can try to work around to make
+ * dosemu and wine happy. */
+ movl PT_OLDESP(%esp), %eax
+ movl %esp, %edx
+ call patch_espfix_desc
+ pushl $__ESPFIX_SS
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ DISABLE_INTERRUPTS(CLBR_EAX)
+ TRACE_IRQS_OFF
+ lss (%esp), %esp
+ CFI_ADJUST_CFA_OFFSET -8
+ jmp restore_nocheck
+ 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
+ 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 $VM_MASK, PT_EFLAGS(%esp)
+ movl %esp, %eax
+ jne work_notifysig_v86 # returning to kernel-space or
+ # vm86-space
+ xorl %edx, %edx
+ call do_notify_resume
+ jmp resume_userspace_sig
+
+ ALIGN
+work_notifysig_v86:
+ pushl %ecx # save ti_flags for do_notify_resume
+ CFI_ADJUST_CFA_OFFSET 4
+ call save_v86_state # %eax contains pt_regs pointer
+ popl %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+ movl %eax, %esp
+#else
+ movl %esp, %eax
+#endif
+ xorl %edx, %edx
+ call do_notify_resume
+ jmp resume_userspace_sig
+END(work_pending)
+
+ # perform syscall exit tracing
+ ALIGN
+syscall_trace_entry:
+ movl $-ENOSYS,PT_EAX(%esp)
+ movl %esp, %eax
+ xorl %edx,%edx
+ call do_syscall_trace
+ cmpl $0, %eax
+ jne resume_userspace # ret != 0 -> running under PTRACE_SYSEMU,
+ # so must skip actual syscall
+ movl PT_ORIG_EAX(%esp), %eax
+ cmpl $(nr_syscalls), %eax
+ jnae syscall_call
+ jmp syscall_exit
+END(syscall_trace_entry)
+
+ # perform syscall exit tracing
+ ALIGN
+syscall_exit_work:
+ testb $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP), %cl
+ jz work_pending
+ TRACE_IRQS_ON
+ ENABLE_INTERRUPTS(CLBR_ANY) # could let do_syscall_trace() call
+ # schedule() instead
+ movl %esp, %eax
+ movl $1, %edx
+ call do_syscall_trace
+ jmp resume_userspace
+END(syscall_exit_work)
+ CFI_ENDPROC
+
+ RING0_INT_FRAME # can't unwind into user space anyway
+syscall_fault:
+ pushl %eax # save orig_eax
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ GET_THREAD_INFO(%ebp)
+ movl $-EFAULT,PT_EAX(%esp)
+ jmp resume_userspace
+END(syscall_fault)
+
+syscall_badsys:
+ movl $-ENOSYS,PT_EAX(%esp)
+ jmp resume_userspace
+END(syscall_badsys)
+ CFI_ENDPROC
+
+#define FIXUP_ESPFIX_STACK \
+ /* since we are on a wrong stack, we cant make it a C code :( */ \
+ PER_CPU(gdt_page, %ebx); \
+ GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah); \
+ addl %esp, %eax; \
+ pushl $__KERNEL_DS; \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ pushl %eax; \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ lss (%esp), %esp; \
+ CFI_ADJUST_CFA_OFFSET -8;
+#define UNWIND_ESPFIX_STACK \
+ 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:;
+
+/*
+ * Build the entry stubs and pointer table with
+ * some assembler magic.
+ */
+.data
+ENTRY(interrupt)
+.text
+
+ENTRY(irq_entries_start)
+ RING0_INT_FRAME
+vector=0
+.rept NR_IRQS
+ ALIGN
+ .if vector
+ CFI_ADJUST_CFA_OFFSET -4
+ .endif
+1: pushl $~(vector)
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp common_interrupt
+ .previous
+ .long 1b
+ .text
+vector=vector+1
+.endr
+END(irq_entries_start)
+
+.previous
+END(interrupt)
+.previous
+
+/*
+ * the CPU automatically disables interrupts when executing an IRQ vector,
+ * so IRQ-flags tracing has to follow that:
+ */
+ ALIGN
+common_interrupt:
+ SAVE_ALL
+ TRACE_IRQS_OFF
+ movl %esp,%eax
+ call do_IRQ
+ jmp ret_from_intr
+ENDPROC(common_interrupt)
+ CFI_ENDPROC
+
+#define BUILD_INTERRUPT(name, nr) \
+ENTRY(name) \
+ RING0_INT_FRAME; \
+ pushl $~(nr); \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ SAVE_ALL; \
+ TRACE_IRQS_OFF \
+ movl %esp,%eax; \
+ call smp_##name; \
+ jmp ret_from_intr; \
+ CFI_ENDPROC; \
+ENDPROC(name)
+
+/* The include is where all of the SMP etc. interrupts come from */
+#include "entry_arch.h"
+
+KPROBE_ENTRY(page_fault)
+ RING0_EC_FRAME
+ pushl $do_page_fault
+ CFI_ADJUST_CFA_OFFSET 4
+ ALIGN
+error_code:
+ /* the function address is in %fs's slot on the stack */
+ pushl %es
+ CFI_ADJUST_CFA_OFFSET 4
+ /*CFI_REL_OFFSET es, 0*/
+ pushl %ds
+ CFI_ADJUST_CFA_OFFSET 4
+ /*CFI_REL_OFFSET ds, 0*/
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET eax, 0
+ pushl %ebp
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ebp, 0
+ pushl %edi
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET edi, 0
+ pushl %esi
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET esi, 0
+ pushl %edx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET edx, 0
+ pushl %ecx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ecx, 0
+ pushl %ebx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ebx, 0
+ cld
+ pushl %fs
+ CFI_ADJUST_CFA_OFFSET 4
+ /*CFI_REL_OFFSET fs, 0*/
+ movl $(__KERNEL_PERCPU), %ecx
+ movl %ecx, %fs
+ UNWIND_ESPFIX_STACK
+ popl %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+ /*CFI_REGISTER es, ecx*/
+ movl PT_FS(%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
+ mov %ecx, PT_FS(%esp)
+ /*CFI_REL_OFFSET fs, ES*/
+ movl $(__USER_DS), %ecx
+ movl %ecx, %ds
+ movl %ecx, %es
+ movl %esp,%eax # pt_regs pointer
+ call *%edi
+ jmp ret_from_exception
+ CFI_ENDPROC
+KPROBE_END(page_fault)
+
+ENTRY(coprocessor_error)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_coprocessor_error
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(coprocessor_error)
+
+ENTRY(simd_coprocessor_error)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_simd_coprocessor_error
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(simd_coprocessor_error)
+
+ENTRY(device_not_available)
+ RING0_INT_FRAME
+ pushl $-1 # mark this as an int
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ GET_CR0_INTO_EAX
+ testl $0x4, %eax # EM (math emulation bit)
+ jne device_not_available_emulate
+ preempt_stop(CLBR_ANY)
+ call math_state_restore
+ jmp ret_from_exception
+device_not_available_emulate:
+ pushl $0 # temporary storage for ORIG_EIP
+ CFI_ADJUST_CFA_OFFSET 4
+ call math_emulate
+ addl $4, %esp
+ CFI_ADJUST_CFA_OFFSET -4
+ jmp ret_from_exception
+ CFI_ENDPROC
+END(device_not_available)
+
+/*
+ * 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_esp0+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.
+ */
+#define FIX_STACK(offset, ok, label) \
+ cmpw $__KERNEL_CS,4(%esp); \
+ jne ok; \
+label: \
+ movl TSS_sysenter_esp0+offset(%esp),%esp; \
+ CFI_DEF_CFA esp, 0; \
+ CFI_UNDEFINED eip; \
+ pushfl; \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ pushl $__KERNEL_CS; \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ pushl $sysenter_past_esp; \
+ CFI_ADJUST_CFA_OFFSET 4; \
+ CFI_REL_OFFSET eip, 0
+
+KPROBE_ENTRY(debug)
+ RING0_INT_FRAME
+ cmpl $sysenter_entry,(%esp)
+ jne debug_stack_correct
+ FIX_STACK(12, debug_stack_correct, debug_esp_fix_insn)
+debug_stack_correct:
+ pushl $-1 # mark this as an int
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ xorl %edx,%edx # error code 0
+ movl %esp,%eax # pt_regs pointer
+ call do_debug
+ jmp ret_from_exception
+ CFI_ENDPROC
+KPROBE_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.
+ */
+KPROBE_ENTRY(nmi)
+ RING0_INT_FRAME
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ movl %ss, %eax
+ cmpw $__ESPFIX_SS, %ax
+ popl %eax
+ CFI_ADJUST_CFA_OFFSET -4
+ je nmi_espfix_stack
+ cmpl $sysenter_entry,(%esp)
+ je nmi_stack_fixup
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ 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 %eax
+ CFI_ADJUST_CFA_OFFSET -4
+ jae nmi_stack_correct
+ cmpl $sysenter_entry,12(%esp)
+ je nmi_debug_stack_check
+nmi_stack_correct:
+ /* We have a RING0_INT_FRAME here */
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ xorl %edx,%edx # zero error code
+ movl %esp,%eax # pt_regs pointer
+ call do_nmi
+ jmp restore_nocheck_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
+
+nmi_espfix_stack:
+ /* We have a RING0_INT_FRAME here.
+ *
+ * create the pointer to lss back
+ */
+ pushl %ss
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl %esp
+ CFI_ADJUST_CFA_OFFSET 4
+ addw $4, (%esp)
+ /* copy the iret frame of 12 bytes */
+ .rept 3
+ pushl 16(%esp)
+ CFI_ADJUST_CFA_OFFSET 4
+ .endr
+ pushl %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ 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
+1: INTERRUPT_RETURN
+ CFI_ENDPROC
+.section __ex_table,"a"
+ .align 4
+ .long 1b,iret_exc
+.previous
+KPROBE_END(nmi)
+
+#ifdef CONFIG_PARAVIRT
+ENTRY(native_iret)
+1: iret
+.section __ex_table,"a"
+ .align 4
+ .long 1b,iret_exc
+.previous
+END(native_iret)
+
+ENTRY(native_irq_enable_sysexit)
+ sti
+ sysexit
+END(native_irq_enable_sysexit)
+#endif
+
+KPROBE_ENTRY(int3)
+ RING0_INT_FRAME
+ pushl $-1 # mark this as an int
+ CFI_ADJUST_CFA_OFFSET 4
+ SAVE_ALL
+ xorl %edx,%edx # zero error code
+ movl %esp,%eax # pt_regs pointer
+ call do_int3
+ jmp ret_from_exception
+ CFI_ENDPROC
+KPROBE_END(int3)
+
+ENTRY(overflow)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_overflow
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(overflow)
+
+ENTRY(bounds)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_bounds
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(bounds)
+
+ENTRY(invalid_op)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_invalid_op
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(invalid_op)
+
+ENTRY(coprocessor_segment_overrun)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_coprocessor_segment_overrun
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(coprocessor_segment_overrun)
+
+ENTRY(invalid_TSS)
+ RING0_EC_FRAME
+ pushl $do_invalid_TSS
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(invalid_TSS)
+
+ENTRY(segment_not_present)
+ RING0_EC_FRAME
+ pushl $do_segment_not_present
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(segment_not_present)
+
+ENTRY(stack_segment)
+ RING0_EC_FRAME
+ pushl $do_stack_segment
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(stack_segment)
+
+KPROBE_ENTRY(general_protection)
+ RING0_EC_FRAME
+ pushl $do_general_protection
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+KPROBE_END(general_protection)
+
+ENTRY(alignment_check)
+ RING0_EC_FRAME
+ pushl $do_alignment_check
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(alignment_check)
+
+ENTRY(divide_error)
+ RING0_INT_FRAME
+ pushl $0 # no error code
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_divide_error
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(divide_error)
+
+#ifdef CONFIG_X86_MCE
+ENTRY(machine_check)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl machine_check_vector
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(machine_check)
+#endif
+
+ENTRY(spurious_interrupt_bug)
+ RING0_INT_FRAME
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ pushl $do_spurious_interrupt_bug
+ CFI_ADJUST_CFA_OFFSET 4
+ jmp error_code
+ CFI_ENDPROC
+END(spurious_interrupt_bug)
+
+ENTRY(kernel_thread_helper)
+ pushl $0 # fake return address for unwinder
+ CFI_STARTPROC
+ movl %edx,%eax
+ push %edx
+ CFI_ADJUST_CFA_OFFSET 4
+ call *%ebx
+ push %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ call do_exit
+ CFI_ENDPROC
+ENDPROC(kernel_thread_helper)
+
+#ifdef CONFIG_XEN
+ENTRY(xen_hypervisor_callback)
+ CFI_STARTPROC
+ pushl $0
+ CFI_ADJUST_CFA_OFFSET 4
+ 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
+
+ call xen_iret_crit_fixup
+
+1: mov %esp, %eax
+ call xen_evtchn_do_upcall
+ 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 %eax
+ CFI_ADJUST_CFA_OFFSET 4
+ movl $1,%eax
+1: mov 4(%esp),%ds
+2: mov 8(%esp),%es
+3: mov 12(%esp),%fs
+4: mov 16(%esp),%gs
+ testl %eax,%eax
+ popl %eax
+ CFI_ADJUST_CFA_OFFSET -4
+ lea 16(%esp),%esp
+ CFI_ADJUST_CFA_OFFSET -16
+ jz 5f
+ addl $16,%esp
+ jmp iret_exc # EAX != 0 => Category 2 (Bad IRET)
+5: pushl $0 # EAX == 0 => Category 1 (Bad segment)
+ CFI_ADJUST_CFA_OFFSET 4
+ 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
+.section __ex_table,"a"
+ .align 4
+ .long 1b,6b
+ .long 2b,7b
+ .long 3b,8b
+ .long 4b,9b
+.previous
+ENDPROC(xen_failsafe_callback)
+
+#endif /* CONFIG_XEN */
+
+.section .rodata,"a"
+#include "syscall_table_32.S"
+
+syscall_table_size=(.-sys_call_table)
projects / deliverable / linux.git / commitdiff
