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Diffstat (limited to 'arch/x86/kernel/entry_32.S')
-rw-r--r--arch/x86/kernel/entry_32.S1401
1 files changed, 0 insertions, 1401 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
deleted file mode 100644
index 1c309763e..000000000
--- a/arch/x86/kernel/entry_32.S
+++ /dev/null
@@ -1,1401 +0,0 @@
-/*
- *
- * 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) - %gs saved iff !CONFIG_X86_32_LAZY_GS
- * 2C(%esp) - orig_eax
- * 30(%esp) - %eip
- * 34(%esp) - %cs
- * 38(%esp) - %eflags
- * 3C(%esp) - %oldesp
- * 40(%esp) - %oldss
- *
- * "current" is in register %ebx during any slow entries.
- */
-
-#include <linux/linkage.h>
-#include <linux/err.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_types.h>
-#include <asm/percpu.h>
-#include <asm/dwarf2.h>
-#include <asm/processor-flags.h>
-#include <asm/ftrace.h>
-#include <asm/irq_vectors.h>
-#include <asm/cpufeature.h>
-#include <asm/alternative-asm.h>
-#include <asm/asm.h>
-#include <asm/smap.h>
-
-/* Avoid __ASSEMBLER__'ifying <linux/audit.h> just for this. */
-#include <linux/elf-em.h>
-#define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE)
-#define __AUDIT_ARCH_LE 0x40000000
-
-#ifndef CONFIG_AUDITSYSCALL
-#define sysenter_audit syscall_trace_entry
-#define sysexit_audit syscall_exit_work
-#endif
-
- .section .entry.text, "ax"
-
-/*
- * 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.
- */
-
-#ifdef CONFIG_PREEMPT
-#define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF
-#else
-#define preempt_stop(clobbers)
-#define resume_kernel restore_all
-#endif
-
-.macro TRACE_IRQS_IRET
-#ifdef CONFIG_TRACE_IRQFLAGS
- testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off?
- jz 1f
- TRACE_IRQS_ON
-1:
-#endif
-.endm
-
-/*
- * User gs save/restore
- *
- * %gs is used for userland TLS and kernel only uses it for stack
- * canary which is required to be at %gs:20 by gcc. Read the comment
- * at the top of stackprotector.h for more info.
- *
- * Local labels 98 and 99 are used.
- */
-#ifdef CONFIG_X86_32_LAZY_GS
-
- /* unfortunately push/pop can't be no-op */
-.macro PUSH_GS
- pushl_cfi $0
-.endm
-.macro POP_GS pop=0
- addl $(4 + \pop), %esp
- CFI_ADJUST_CFA_OFFSET -(4 + \pop)
-.endm
-.macro POP_GS_EX
-.endm
-
- /* all the rest are no-op */
-.macro PTGS_TO_GS
-.endm
-.macro PTGS_TO_GS_EX
-.endm
-.macro GS_TO_REG reg
-.endm
-.macro REG_TO_PTGS reg
-.endm
-.macro SET_KERNEL_GS reg
-.endm
-
-#else /* CONFIG_X86_32_LAZY_GS */
-
-.macro PUSH_GS
- pushl_cfi %gs
- /*CFI_REL_OFFSET gs, 0*/
-.endm
-
-.macro POP_GS pop=0
-98: popl_cfi %gs
- /*CFI_RESTORE gs*/
- .if \pop <> 0
- add $\pop, %esp
- CFI_ADJUST_CFA_OFFSET -\pop
- .endif
-.endm
-.macro POP_GS_EX
-.pushsection .fixup, "ax"
-99: movl $0, (%esp)
- jmp 98b
-.popsection
- _ASM_EXTABLE(98b,99b)
-.endm
-
-.macro PTGS_TO_GS
-98: mov PT_GS(%esp), %gs
-.endm
-.macro PTGS_TO_GS_EX
-.pushsection .fixup, "ax"
-99: movl $0, PT_GS(%esp)
- jmp 98b
-.popsection
- _ASM_EXTABLE(98b,99b)
-.endm
-
-.macro GS_TO_REG reg
- movl %gs, \reg
- /*CFI_REGISTER gs, \reg*/
-.endm
-.macro REG_TO_PTGS reg
- movl \reg, PT_GS(%esp)
- /*CFI_REL_OFFSET gs, PT_GS*/
-.endm
-.macro SET_KERNEL_GS reg
- movl $(__KERNEL_STACK_CANARY), \reg
- movl \reg, %gs
-.endm
-
-#endif /* CONFIG_X86_32_LAZY_GS */
-
-.macro SAVE_ALL
- cld
- PUSH_GS
- 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 %eax
- CFI_REL_OFFSET eax, 0
- pushl_cfi %ebp
- CFI_REL_OFFSET ebp, 0
- pushl_cfi %edi
- CFI_REL_OFFSET edi, 0
- pushl_cfi %esi
- CFI_REL_OFFSET esi, 0
- pushl_cfi %edx
- CFI_REL_OFFSET edx, 0
- pushl_cfi %ecx
- CFI_REL_OFFSET ecx, 0
- pushl_cfi %ebx
- CFI_REL_OFFSET ebx, 0
- movl $(__USER_DS), %edx
- movl %edx, %ds
- movl %edx, %es
- movl $(__KERNEL_PERCPU), %edx
- movl %edx, %fs
- SET_KERNEL_GS %edx
-.endm
-
-.macro RESTORE_INT_REGS
- popl_cfi %ebx
- CFI_RESTORE ebx
- popl_cfi %ecx
- CFI_RESTORE ecx
- popl_cfi %edx
- CFI_RESTORE edx
- popl_cfi %esi
- CFI_RESTORE esi
- popl_cfi %edi
- CFI_RESTORE edi
- popl_cfi %ebp
- CFI_RESTORE ebp
- popl_cfi %eax
- CFI_RESTORE eax
-.endm
-
-.macro RESTORE_REGS pop=0
- RESTORE_INT_REGS
-1: popl_cfi %ds
- /*CFI_RESTORE ds;*/
-2: popl_cfi %es
- /*CFI_RESTORE es;*/
-3: popl_cfi %fs
- /*CFI_RESTORE fs;*/
- POP_GS \pop
-.pushsection .fixup, "ax"
-4: movl $0, (%esp)
- jmp 1b
-5: movl $0, (%esp)
- jmp 2b
-6: movl $0, (%esp)
- jmp 3b
-.popsection
- _ASM_EXTABLE(1b,4b)
- _ASM_EXTABLE(2b,5b)
- _ASM_EXTABLE(3b,6b)
- POP_GS_EX
-.endm
-
-.macro 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
-.endm
-
-.macro 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
-.endm
-
-.macro 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
-.endm
-
-ENTRY(ret_from_fork)
- CFI_STARTPROC
- pushl_cfi %eax
- call schedule_tail
- GET_THREAD_INFO(%ebp)
- popl_cfi %eax
- pushl_cfi $0x0202 # Reset kernel eflags
- popfl_cfi
- jmp syscall_exit
- CFI_ENDPROC
-END(ret_from_fork)
-
-ENTRY(ret_from_kernel_thread)
- CFI_STARTPROC
- pushl_cfi %eax
- call schedule_tail
- GET_THREAD_INFO(%ebp)
- popl_cfi %eax
- pushl_cfi $0x0202 # Reset kernel eflags
- popfl_cfi
- movl PT_EBP(%esp),%eax
- call *PT_EBX(%esp)
- movl $0,PT_EAX(%esp)
- jmp syscall_exit
- CFI_ENDPROC
-ENDPROC(ret_from_kernel_thread)
-
-/*
- * 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)
-#ifdef CONFIG_VM86
- movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS
- movb PT_CS(%esp), %al
- andl $(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax
-#else
- /*
- * We can be coming here from child spawned by kernel_thread().
- */
- movl PT_CS(%esp), %eax
- andl $SEGMENT_RPL_MASK, %eax
-#endif
- cmpl $USER_RPL, %eax
- jb resume_kernel # not returning to v8086 or userspace
-
-ENTRY(resume_userspace)
- 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 on
- # int/exception return?
- jne work_pending
- jmp restore_all
-END(ret_from_exception)
-
-#ifdef CONFIG_PREEMPT
-ENTRY(resume_kernel)
- DISABLE_INTERRUPTS(CLBR_ANY)
-need_resched:
- cmpl $0,PER_CPU_VAR(__preempt_count)
- jnz restore_all
- testl $X86_EFLAGS_IF,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(ia32_sysenter_target)
- CFI_STARTPROC simple
- CFI_SIGNAL_FRAME
- CFI_DEF_CFA esp, 0
- CFI_REGISTER esp, ebp
- movl TSS_sysenter_sp0(%esp),%esp
-sysenter_past_esp:
- /*
- * Interrupts are disabled here, but we can't trace it until
- * enough kernel state to call TRACE_IRQS_OFF can be called - but
- * we immediately enable interrupts at that point anyway.
- */
- pushl_cfi $__USER_DS
- /*CFI_REL_OFFSET ss, 0*/
- pushl_cfi %ebp
- CFI_REL_OFFSET esp, 0
- pushfl_cfi
- orl $X86_EFLAGS_IF, (%esp)
- pushl_cfi $__USER_CS
- /*CFI_REL_OFFSET cs, 0*/
- /*
- * Push current_thread_info()->sysenter_return to the stack.
- * A tiny bit of offset fixup is necessary: TI_sysenter_return
- * is relative to thread_info, which is at the bottom of the
- * kernel stack page. 4*4 means the 4 words pushed above;
- * TOP_OF_KERNEL_STACK_PADDING takes us to the top of the stack;
- * and THREAD_SIZE takes us to the bottom.
- */
- 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, &regs->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
-