10ffdbb8d6
Cleans up the system exit call slightly and synchronizes with my tree again. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
921 lines
20 KiB
ArmAsm
921 lines
20 KiB
ArmAsm
/*
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* linux/arch/x86_64/entry.S
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
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* Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
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*
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* $Id$
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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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*
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* NOTE: This code handles signal-recognition, which happens every time
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* after an interrupt and after each system call.
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*
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* Normal syscalls and interrupts don't save a full stack frame, this is
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* only done for syscall tracing, signals or fork/exec et.al.
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*
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* A note on terminology:
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* - top of stack: Architecture defined interrupt frame from SS to RIP
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* at the top of the kernel process stack.
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* - partial stack frame: partially saved registers upto R11.
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* - full stack frame: Like partial stack frame, but all register saved.
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*
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* TODO:
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* - schedule it carefully for the final hardware.
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*/
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#define ASSEMBLY 1
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#include <linux/config.h>
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#include <linux/linkage.h>
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#include <asm/segment.h>
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#include <asm/smp.h>
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#include <asm/cache.h>
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#include <asm/errno.h>
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#include <asm/dwarf2.h>
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#include <asm/calling.h>
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#include <asm/offset.h>
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#include <asm/msr.h>
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#include <asm/unistd.h>
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#include <asm/thread_info.h>
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#include <asm/hw_irq.h>
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.code64
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#ifndef CONFIG_PREEMPT
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#define retint_kernel retint_restore_args
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#endif
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/*
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* C code is not supposed to know about undefined top of stack. Every time
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* a C function with an pt_regs argument is called from the SYSCALL based
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* fast path FIXUP_TOP_OF_STACK is needed.
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* RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs
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* manipulation.
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*/
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/* %rsp:at FRAMEEND */
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.macro FIXUP_TOP_OF_STACK tmp
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movq %gs:pda_oldrsp,\tmp
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movq \tmp,RSP(%rsp)
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movq $__USER_DS,SS(%rsp)
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movq $__USER_CS,CS(%rsp)
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movq $-1,RCX(%rsp)
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movq R11(%rsp),\tmp /* get eflags */
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movq \tmp,EFLAGS(%rsp)
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.endm
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.macro RESTORE_TOP_OF_STACK tmp,offset=0
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movq RSP-\offset(%rsp),\tmp
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movq \tmp,%gs:pda_oldrsp
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movq EFLAGS-\offset(%rsp),\tmp
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movq \tmp,R11-\offset(%rsp)
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.endm
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.macro FAKE_STACK_FRAME child_rip
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/* push in order ss, rsp, eflags, cs, rip */
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xorq %rax, %rax
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pushq %rax /* ss */
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CFI_ADJUST_CFA_OFFSET 8
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pushq %rax /* rsp */
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CFI_ADJUST_CFA_OFFSET 8
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CFI_OFFSET rip,0
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pushq $(1<<9) /* eflags - interrupts on */
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CFI_ADJUST_CFA_OFFSET 8
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pushq $__KERNEL_CS /* cs */
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CFI_ADJUST_CFA_OFFSET 8
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pushq \child_rip /* rip */
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CFI_ADJUST_CFA_OFFSET 8
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CFI_OFFSET rip,0
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pushq %rax /* orig rax */
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CFI_ADJUST_CFA_OFFSET 8
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.endm
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.macro UNFAKE_STACK_FRAME
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addq $8*6, %rsp
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CFI_ADJUST_CFA_OFFSET -(6*8)
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.endm
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.macro CFI_DEFAULT_STACK
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CFI_ADJUST_CFA_OFFSET (SS)
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CFI_OFFSET r15,R15-SS
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CFI_OFFSET r14,R14-SS
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CFI_OFFSET r13,R13-SS
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CFI_OFFSET r12,R12-SS
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CFI_OFFSET rbp,RBP-SS
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CFI_OFFSET rbx,RBX-SS
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CFI_OFFSET r11,R11-SS
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CFI_OFFSET r10,R10-SS
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CFI_OFFSET r9,R9-SS
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CFI_OFFSET r8,R8-SS
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CFI_OFFSET rax,RAX-SS
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CFI_OFFSET rcx,RCX-SS
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CFI_OFFSET rdx,RDX-SS
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CFI_OFFSET rsi,RSI-SS
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CFI_OFFSET rdi,RDI-SS
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CFI_OFFSET rsp,RSP-SS
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CFI_OFFSET rip,RIP-SS
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.endm
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/*
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* A newly forked process directly context switches into this.
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*/
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/* rdi: prev */
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ENTRY(ret_from_fork)
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CFI_STARTPROC
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CFI_DEFAULT_STACK
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call schedule_tail
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GET_THREAD_INFO(%rcx)
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testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),threadinfo_flags(%rcx)
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jnz rff_trace
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rff_action:
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RESTORE_REST
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testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread?
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je int_ret_from_sys_call
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testl $_TIF_IA32,threadinfo_flags(%rcx)
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jnz int_ret_from_sys_call
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RESTORE_TOP_OF_STACK %rdi,ARGOFFSET
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jmp ret_from_sys_call
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rff_trace:
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movq %rsp,%rdi
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call syscall_trace_leave
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GET_THREAD_INFO(%rcx)
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jmp rff_action
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CFI_ENDPROC
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/*
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* System call entry. Upto 6 arguments in registers are supported.
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*
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* SYSCALL does not save anything on the stack and does not change the
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* stack pointer.
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*/
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/*
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* Register setup:
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* rax system call number
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* rdi arg0
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* rcx return address for syscall/sysret, C arg3
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* rsi arg1
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* rdx arg2
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* r10 arg3 (--> moved to rcx for C)
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* r8 arg4
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* r9 arg5
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* r11 eflags for syscall/sysret, temporary for C
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* r12-r15,rbp,rbx saved by C code, not touched.
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*
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* Interrupts are off on entry.
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* Only called from user space.
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*
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* XXX if we had a free scratch register we could save the RSP into the stack frame
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* and report it properly in ps. Unfortunately we haven't.
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*/
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ENTRY(system_call)
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CFI_STARTPROC
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swapgs
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movq %rsp,%gs:pda_oldrsp
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movq %gs:pda_kernelstack,%rsp
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sti
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SAVE_ARGS 8,1
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movq %rax,ORIG_RAX-ARGOFFSET(%rsp)
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movq %rcx,RIP-ARGOFFSET(%rsp)
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GET_THREAD_INFO(%rcx)
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testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP),threadinfo_flags(%rcx)
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jnz tracesys
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cmpq $__NR_syscall_max,%rax
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ja badsys
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movq %r10,%rcx
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call *sys_call_table(,%rax,8) # XXX: rip relative
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movq %rax,RAX-ARGOFFSET(%rsp)
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/*
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* Syscall return path ending with SYSRET (fast path)
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* Has incomplete stack frame and undefined top of stack.
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*/
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.globl ret_from_sys_call
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ret_from_sys_call:
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movl $_TIF_ALLWORK_MASK,%edi
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/* edi: flagmask */
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sysret_check:
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GET_THREAD_INFO(%rcx)
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cli
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movl threadinfo_flags(%rcx),%edx
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andl %edi,%edx
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jnz sysret_careful
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movq RIP-ARGOFFSET(%rsp),%rcx
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RESTORE_ARGS 0,-ARG_SKIP,1
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movq %gs:pda_oldrsp,%rsp
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swapgs
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sysretq
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/* Handle reschedules */
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/* edx: work, edi: workmask */
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sysret_careful:
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bt $TIF_NEED_RESCHED,%edx
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jnc sysret_signal
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sti
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pushq %rdi
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call schedule
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popq %rdi
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jmp sysret_check
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/* Handle a signal */
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sysret_signal:
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sti
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testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx
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jz 1f
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/* Really a signal */
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/* edx: work flags (arg3) */
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leaq do_notify_resume(%rip),%rax
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leaq -ARGOFFSET(%rsp),%rdi # &pt_regs -> arg1
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xorl %esi,%esi # oldset -> arg2
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call ptregscall_common
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1: movl $_TIF_NEED_RESCHED,%edi
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jmp sysret_check
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/* Do syscall tracing */
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tracesys:
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SAVE_REST
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movq $-ENOSYS,RAX(%rsp)
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FIXUP_TOP_OF_STACK %rdi
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movq %rsp,%rdi
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call syscall_trace_enter
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LOAD_ARGS ARGOFFSET /* reload args from stack in case ptrace changed it */
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RESTORE_REST
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cmpq $__NR_syscall_max,%rax
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ja 1f
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movq %r10,%rcx /* fixup for C */
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call *sys_call_table(,%rax,8)
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movq %rax,RAX-ARGOFFSET(%rsp)
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1: SAVE_REST
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movq %rsp,%rdi
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call syscall_trace_leave
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RESTORE_TOP_OF_STACK %rbx
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RESTORE_REST
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jmp ret_from_sys_call
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badsys:
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movq $-ENOSYS,RAX-ARGOFFSET(%rsp)
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jmp ret_from_sys_call
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/*
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* Syscall return path ending with IRET.
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* Has correct top of stack, but partial stack frame.
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*/
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ENTRY(int_ret_from_sys_call)
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cli
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testl $3,CS-ARGOFFSET(%rsp)
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je retint_restore_args
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movl $_TIF_ALLWORK_MASK,%edi
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/* edi: mask to check */
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int_with_check:
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GET_THREAD_INFO(%rcx)
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movl threadinfo_flags(%rcx),%edx
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andl %edi,%edx
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jnz int_careful
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jmp retint_swapgs
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/* Either reschedule or signal or syscall exit tracking needed. */
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/* First do a reschedule test. */
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/* edx: work, edi: workmask */
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int_careful:
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bt $TIF_NEED_RESCHED,%edx
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jnc int_very_careful
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sti
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pushq %rdi
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call schedule
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popq %rdi
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cli
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jmp int_with_check
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/* handle signals and tracing -- both require a full stack frame */
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int_very_careful:
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sti
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SAVE_REST
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/* Check for syscall exit trace */
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testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edx
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jz int_signal
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pushq %rdi
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leaq 8(%rsp),%rdi # &ptregs -> arg1
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call syscall_trace_leave
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popq %rdi
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andl $~(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edi
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cli
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jmp int_restore_rest
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int_signal:
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testl $(_TIF_NOTIFY_RESUME|_TIF_SIGPENDING|_TIF_SINGLESTEP),%edx
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jz 1f
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movq %rsp,%rdi # &ptregs -> arg1
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xorl %esi,%esi # oldset -> arg2
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call do_notify_resume
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1: movl $_TIF_NEED_RESCHED,%edi
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int_restore_rest:
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RESTORE_REST
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cli
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jmp int_with_check
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CFI_ENDPROC
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/*
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* Certain special system calls that need to save a complete full stack frame.
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*/
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.macro PTREGSCALL label,func,arg
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.globl \label
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\label:
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leaq \func(%rip),%rax
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leaq -ARGOFFSET+8(%rsp),\arg /* 8 for return address */
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jmp ptregscall_common
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.endm
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PTREGSCALL stub_clone, sys_clone, %r8
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PTREGSCALL stub_fork, sys_fork, %rdi
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PTREGSCALL stub_vfork, sys_vfork, %rdi
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PTREGSCALL stub_rt_sigsuspend, sys_rt_sigsuspend, %rdx
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PTREGSCALL stub_sigaltstack, sys_sigaltstack, %rdx
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PTREGSCALL stub_iopl, sys_iopl, %rsi
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ENTRY(ptregscall_common)
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CFI_STARTPROC
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popq %r11
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CFI_ADJUST_CFA_OFFSET -8
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SAVE_REST
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movq %r11, %r15
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FIXUP_TOP_OF_STACK %r11
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call *%rax
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RESTORE_TOP_OF_STACK %r11
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movq %r15, %r11
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RESTORE_REST
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pushq %r11
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CFI_ADJUST_CFA_OFFSET 8
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ret
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CFI_ENDPROC
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ENTRY(stub_execve)
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CFI_STARTPROC
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popq %r11
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CFI_ADJUST_CFA_OFFSET -8
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SAVE_REST
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movq %r11, %r15
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FIXUP_TOP_OF_STACK %r11
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call sys_execve
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GET_THREAD_INFO(%rcx)
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bt $TIF_IA32,threadinfo_flags(%rcx)
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jc exec_32bit
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RESTORE_TOP_OF_STACK %r11
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movq %r15, %r11
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RESTORE_REST
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push %r11
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ret
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exec_32bit:
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CFI_ADJUST_CFA_OFFSET REST_SKIP
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movq %rax,RAX(%rsp)
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RESTORE_REST
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jmp int_ret_from_sys_call
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CFI_ENDPROC
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/*
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* sigreturn is special because it needs to restore all registers on return.
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* This cannot be done with SYSRET, so use the IRET return path instead.
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*/
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ENTRY(stub_rt_sigreturn)
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CFI_STARTPROC
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addq $8, %rsp
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SAVE_REST
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movq %rsp,%rdi
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FIXUP_TOP_OF_STACK %r11
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call sys_rt_sigreturn
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movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer
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RESTORE_REST
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jmp int_ret_from_sys_call
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CFI_ENDPROC
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/*
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* Interrupt entry/exit.
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*
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* Interrupt entry points save only callee clobbered registers in fast path.
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*
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* Entry runs with interrupts off.
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*/
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/* 0(%rsp): interrupt number */
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.macro interrupt func
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CFI_STARTPROC simple
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CFI_DEF_CFA rsp,(SS-RDI)
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CFI_REL_OFFSET rsp,(RSP-ORIG_RAX)
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CFI_REL_OFFSET rip,(RIP-ORIG_RAX)
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cld
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#ifdef CONFIG_DEBUG_INFO
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SAVE_ALL
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movq %rsp,%rdi
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/*
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* Setup a stack frame pointer. This allows gdb to trace
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* back to the original stack.
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*/
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movq %rsp,%rbp
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CFI_DEF_CFA_REGISTER rbp
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#else
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SAVE_ARGS
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leaq -ARGOFFSET(%rsp),%rdi # arg1 for handler
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#endif
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testl $3,CS(%rdi)
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je 1f
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swapgs
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1: addl $1,%gs:pda_irqcount # RED-PEN should check preempt count
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movq %gs:pda_irqstackptr,%rax
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cmoveq %rax,%rsp
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pushq %rdi # save old stack
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call \func
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.endm
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ENTRY(common_interrupt)
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interrupt do_IRQ
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/* 0(%rsp): oldrsp-ARGOFFSET */
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ret_from_intr:
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popq %rdi
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cli
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subl $1,%gs:pda_irqcount
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#ifdef CONFIG_DEBUG_INFO
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movq RBP(%rdi),%rbp
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#endif
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leaq ARGOFFSET(%rdi),%rsp
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exit_intr:
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GET_THREAD_INFO(%rcx)
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testl $3,CS-ARGOFFSET(%rsp)
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je retint_kernel
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/* Interrupt came from user space */
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/*
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* Has a correct top of stack, but a partial stack frame
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* %rcx: thread info. Interrupts off.
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*/
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retint_with_reschedule:
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movl $_TIF_WORK_MASK,%edi
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retint_check:
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movl threadinfo_flags(%rcx),%edx
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andl %edi,%edx
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jnz retint_careful
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retint_swapgs:
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swapgs
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retint_restore_args:
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cli
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RESTORE_ARGS 0,8,0
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iret_label:
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iretq
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.section __ex_table,"a"
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.quad iret_label,bad_iret
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.previous
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.section .fixup,"ax"
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/* force a signal here? this matches i386 behaviour */
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/* running with kernel gs */
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bad_iret:
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movq $-9999,%rdi /* better code? */
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jmp do_exit
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.previous
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/* edi: workmask, edx: work */
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retint_careful:
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bt $TIF_NEED_RESCHED,%edx
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jnc retint_signal
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sti
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pushq %rdi
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call schedule
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popq %rdi
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GET_THREAD_INFO(%rcx)
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cli
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jmp retint_check
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retint_signal:
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testl $(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME|_TIF_SINGLESTEP),%edx
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jz retint_swapgs
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sti
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SAVE_REST
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movq $-1,ORIG_RAX(%rsp)
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xorq %rsi,%rsi # oldset
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movq %rsp,%rdi # &pt_regs
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call do_notify_resume
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RESTORE_REST
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cli
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movl $_TIF_NEED_RESCHED,%edi
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GET_THREAD_INFO(%rcx)
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jmp retint_check
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#ifdef CONFIG_PREEMPT
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/* Returning to kernel space. Check if we need preemption */
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/* rcx: threadinfo. interrupts off. */
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.p2align
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retint_kernel:
|
|
cmpl $0,threadinfo_preempt_count(%rcx)
|
|
jnz retint_restore_args
|
|
bt $TIF_NEED_RESCHED,threadinfo_flags(%rcx)
|
|
jnc retint_restore_args
|
|
bt $9,EFLAGS-ARGOFFSET(%rsp) /* interrupts off? */
|
|
jnc retint_restore_args
|
|
call preempt_schedule_irq
|
|
jmp exit_intr
|
|
#endif
|
|
CFI_ENDPROC
|
|
|
|
/*
|
|
* APIC interrupts.
|
|
*/
|
|
.macro apicinterrupt num,func
|
|
pushq $\num-256
|
|
interrupt \func
|
|
jmp ret_from_intr
|
|
CFI_ENDPROC
|
|
.endm
|
|
|
|
ENTRY(thermal_interrupt)
|
|
apicinterrupt THERMAL_APIC_VECTOR,smp_thermal_interrupt
|
|
|
|
#ifdef CONFIG_SMP
|
|
ENTRY(reschedule_interrupt)
|
|
apicinterrupt RESCHEDULE_VECTOR,smp_reschedule_interrupt
|
|
|
|
ENTRY(invalidate_interrupt)
|
|
apicinterrupt INVALIDATE_TLB_VECTOR,smp_invalidate_interrupt
|
|
|
|
ENTRY(call_function_interrupt)
|
|
apicinterrupt CALL_FUNCTION_VECTOR,smp_call_function_interrupt
|
|
#endif
|
|
|
|
#ifdef CONFIG_X86_LOCAL_APIC
|
|
ENTRY(apic_timer_interrupt)
|
|
apicinterrupt LOCAL_TIMER_VECTOR,smp_apic_timer_interrupt
|
|
|
|
ENTRY(error_interrupt)
|
|
apicinterrupt ERROR_APIC_VECTOR,smp_error_interrupt
|
|
|
|
ENTRY(spurious_interrupt)
|
|
apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt
|
|
#endif
|
|
|
|
/*
|
|
* Exception entry points.
|
|
*/
|
|
.macro zeroentry sym
|
|
pushq $0 /* push error code/oldrax */
|
|
pushq %rax /* push real oldrax to the rdi slot */
|
|
leaq \sym(%rip),%rax
|
|
jmp error_entry
|
|
.endm
|
|
|
|
.macro errorentry sym
|
|
pushq %rax
|
|
leaq \sym(%rip),%rax
|
|
jmp error_entry
|
|
.endm
|
|
|
|
/* error code is on the stack already */
|
|
/* handle NMI like exceptions that can happen everywhere */
|
|
.macro paranoidentry sym
|
|
SAVE_ALL
|
|
cld
|
|
movl $1,%ebx
|
|
movl $MSR_GS_BASE,%ecx
|
|
rdmsr
|
|
testl %edx,%edx
|
|
js 1f
|
|
swapgs
|
|
xorl %ebx,%ebx
|
|
1: movq %rsp,%rdi
|
|
movq ORIG_RAX(%rsp),%rsi
|
|
movq $-1,ORIG_RAX(%rsp)
|
|
call \sym
|
|
cli
|
|
.endm
|
|
|
|
/*
|
|
* Exception entry point. This expects an error code/orig_rax on the stack
|
|
* and the exception handler in %rax.
|
|
*/
|
|
ENTRY(error_entry)
|
|
CFI_STARTPROC simple
|
|
CFI_DEF_CFA rsp,(SS-RDI)
|
|
CFI_REL_OFFSET rsp,(RSP-RDI)
|
|
CFI_REL_OFFSET rip,(RIP-RDI)
|
|
/* rdi slot contains rax, oldrax contains error code */
|
|
cld
|
|
subq $14*8,%rsp
|
|
CFI_ADJUST_CFA_OFFSET (14*8)
|
|
movq %rsi,13*8(%rsp)
|
|
CFI_REL_OFFSET rsi,RSI
|
|
movq 14*8(%rsp),%rsi /* load rax from rdi slot */
|
|
movq %rdx,12*8(%rsp)
|
|
CFI_REL_OFFSET rdx,RDX
|
|
movq %rcx,11*8(%rsp)
|
|
CFI_REL_OFFSET rcx,RCX
|
|
movq %rsi,10*8(%rsp) /* store rax */
|
|
CFI_REL_OFFSET rax,RAX
|
|
movq %r8, 9*8(%rsp)
|
|
CFI_REL_OFFSET r8,R8
|
|
movq %r9, 8*8(%rsp)
|
|
CFI_REL_OFFSET r9,R9
|
|
movq %r10,7*8(%rsp)
|
|
CFI_REL_OFFSET r10,R10
|
|
movq %r11,6*8(%rsp)
|
|
CFI_REL_OFFSET r11,R11
|
|
movq %rbx,5*8(%rsp)
|
|
CFI_REL_OFFSET rbx,RBX
|
|
movq %rbp,4*8(%rsp)
|
|
CFI_REL_OFFSET rbp,RBP
|
|
movq %r12,3*8(%rsp)
|
|
CFI_REL_OFFSET r12,R12
|
|
movq %r13,2*8(%rsp)
|
|
CFI_REL_OFFSET r13,R13
|
|
movq %r14,1*8(%rsp)
|
|
CFI_REL_OFFSET r14,R14
|
|
movq %r15,(%rsp)
|
|
CFI_REL_OFFSET r15,R15
|
|
xorl %ebx,%ebx
|
|
testl $3,CS(%rsp)
|
|
je error_kernelspace
|
|
error_swapgs:
|
|
swapgs
|
|
error_sti:
|
|
movq %rdi,RDI(%rsp)
|
|
movq %rsp,%rdi
|
|
movq ORIG_RAX(%rsp),%rsi /* get error code */
|
|
movq $-1,ORIG_RAX(%rsp)
|
|
call *%rax
|
|
/* ebx: no swapgs flag (1: don't need swapgs, 0: need it) */
|
|
error_exit:
|
|
movl %ebx,%eax
|
|
RESTORE_REST
|
|
cli
|
|
GET_THREAD_INFO(%rcx)
|
|
testl %eax,%eax
|
|
jne retint_kernel
|
|
movl threadinfo_flags(%rcx),%edx
|
|
movl $_TIF_WORK_MASK,%edi
|
|
andl %edi,%edx
|
|
jnz retint_careful
|
|
swapgs
|
|
RESTORE_ARGS 0,8,0
|
|
iretq
|
|
CFI_ENDPROC
|
|
|
|
error_kernelspace:
|
|
incl %ebx
|
|
/* There are two places in the kernel that can potentially fault with
|
|
usergs. Handle them here. The exception handlers after
|
|
iret run with kernel gs again, so don't set the user space flag.
|
|
B stepping K8s sometimes report an truncated RIP for IRET
|
|
exceptions returning to compat mode. Check for these here too. */
|
|
leaq iret_label(%rip),%rbp
|
|
cmpq %rbp,RIP(%rsp)
|
|
je error_swapgs
|
|
movl %ebp,%ebp /* zero extend */
|
|
cmpq %rbp,RIP(%rsp)
|
|
je error_swapgs
|
|
cmpq $gs_change,RIP(%rsp)
|
|
je error_swapgs
|
|
jmp error_sti
|
|
|
|
/* Reload gs selector with exception handling */
|
|
/* edi: new selector */
|
|
ENTRY(load_gs_index)
|
|
pushf
|
|
cli
|
|
swapgs
|
|
gs_change:
|
|
movl %edi,%gs
|
|
2: mfence /* workaround */
|
|
swapgs
|
|
popf
|
|
ret
|
|
|
|
.section __ex_table,"a"
|
|
.align 8
|
|
.quad gs_change,bad_gs
|
|
.previous
|
|
.section .fixup,"ax"
|
|
/* running with kernelgs */
|
|
bad_gs:
|
|
swapgs /* switch back to user gs */
|
|
xorl %eax,%eax
|
|
movl %eax,%gs
|
|
jmp 2b
|
|
.previous
|
|
|
|
/*
|
|
* Create a kernel thread.
|
|
*
|
|
* C extern interface:
|
|
* extern long kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
|
|
*
|
|
* asm input arguments:
|
|
* rdi: fn, rsi: arg, rdx: flags
|
|
*/
|
|
ENTRY(kernel_thread)
|
|
CFI_STARTPROC
|
|
FAKE_STACK_FRAME $child_rip
|
|
SAVE_ALL
|
|
|
|
# rdi: flags, rsi: usp, rdx: will be &pt_regs
|
|
movq %rdx,%rdi
|
|
orq kernel_thread_flags(%rip),%rdi
|
|
movq $-1, %rsi
|
|
movq %rsp, %rdx
|
|
|
|
xorl %r8d,%r8d
|
|
xorl %r9d,%r9d
|
|
|
|
# clone now
|
|
call do_fork
|
|
movq %rax,RAX(%rsp)
|
|
xorl %edi,%edi
|
|
|
|
/*
|
|
* It isn't worth to check for reschedule here,
|
|
* so internally to the x86_64 port you can rely on kernel_thread()
|
|
* not to reschedule the child before returning, this avoids the need
|
|
* of hacks for example to fork off the per-CPU idle tasks.
|
|
* [Hopefully no generic code relies on the reschedule -AK]
|
|
*/
|
|
RESTORE_ALL
|
|
UNFAKE_STACK_FRAME
|
|
ret
|
|
CFI_ENDPROC
|
|
|
|
|
|
child_rip:
|
|
/*
|
|
* Here we are in the child and the registers are set as they were
|
|
* at kernel_thread() invocation in the parent.
|
|
*/
|
|
movq %rdi, %rax
|
|
movq %rsi, %rdi
|
|
call *%rax
|
|
# exit
|
|
xorq %rdi, %rdi
|
|
call do_exit
|
|
|
|
/*
|
|
* execve(). This function needs to use IRET, not SYSRET, to set up all state properly.
|
|
*
|
|
* C extern interface:
|
|
* extern long execve(char *name, char **argv, char **envp)
|
|
*
|
|
* asm input arguments:
|
|
* rdi: name, rsi: argv, rdx: envp
|
|
*
|
|
* We want to fallback into:
|
|
* extern long sys_execve(char *name, char **argv,char **envp, struct pt_regs regs)
|
|
*
|
|
* do_sys_execve asm fallback arguments:
|
|
* rdi: name, rsi: argv, rdx: envp, fake frame on the stack
|
|
*/
|
|
ENTRY(execve)
|
|
CFI_STARTPROC
|
|
FAKE_STACK_FRAME $0
|
|
SAVE_ALL
|
|
call sys_execve
|
|
movq %rax, RAX(%rsp)
|
|
RESTORE_REST
|
|
testq %rax,%rax
|
|
je int_ret_from_sys_call
|
|
RESTORE_ARGS
|
|
UNFAKE_STACK_FRAME
|
|
ret
|
|
CFI_ENDPROC
|
|
|
|
ENTRY(page_fault)
|
|
errorentry do_page_fault
|
|
|
|
ENTRY(coprocessor_error)
|
|
zeroentry do_coprocessor_error
|
|
|
|
ENTRY(simd_coprocessor_error)
|
|
zeroentry do_simd_coprocessor_error
|
|
|
|
ENTRY(device_not_available)
|
|
zeroentry math_state_restore
|
|
|
|
/* runs on exception stack */
|
|
ENTRY(debug)
|
|
CFI_STARTPROC
|
|
pushq $0
|
|
CFI_ADJUST_CFA_OFFSET 8
|
|
paranoidentry do_debug
|
|
jmp paranoid_exit
|
|
CFI_ENDPROC
|
|
|
|
/* runs on exception stack */
|
|
ENTRY(nmi)
|
|
CFI_STARTPROC
|
|
pushq $-1
|
|
CFI_ADJUST_CFA_OFFSET 8
|
|
paranoidentry do_nmi
|
|
/*
|
|
* "Paranoid" exit path from exception stack.
|
|
* Paranoid because this is used by NMIs and cannot take
|
|
* any kernel state for granted.
|
|
* We don't do kernel preemption checks here, because only
|
|
* NMI should be common and it does not enable IRQs and
|
|
* cannot get reschedule ticks.
|
|
*/
|
|
/* ebx: no swapgs flag */
|
|
paranoid_exit:
|
|
testl %ebx,%ebx /* swapgs needed? */
|
|
jnz paranoid_restore
|
|
testl $3,CS(%rsp)
|
|
jnz paranoid_userspace
|
|
paranoid_swapgs:
|
|
swapgs
|
|
paranoid_restore:
|
|
RESTORE_ALL 8
|
|
iretq
|
|
paranoid_userspace:
|
|
GET_THREAD_INFO(%rcx)
|
|
movl threadinfo_flags(%rcx),%ebx
|
|
andl $_TIF_WORK_MASK,%ebx
|
|
jz paranoid_swapgs
|
|
movq %rsp,%rdi /* &pt_regs */
|
|
call sync_regs
|
|
movq %rax,%rsp /* switch stack for scheduling */
|
|
testl $_TIF_NEED_RESCHED,%ebx
|
|
jnz paranoid_schedule
|
|
movl %ebx,%edx /* arg3: thread flags */
|
|
sti
|
|
xorl %esi,%esi /* arg2: oldset */
|
|
movq %rsp,%rdi /* arg1: &pt_regs */
|
|
call do_notify_resume
|
|
cli
|
|
jmp paranoid_userspace
|
|
paranoid_schedule:
|
|
sti
|
|
call schedule
|
|
cli
|
|
jmp paranoid_userspace
|
|
CFI_ENDPROC
|
|
|
|
ENTRY(int3)
|
|
zeroentry do_int3
|
|
|
|
ENTRY(overflow)
|
|
zeroentry do_overflow
|
|
|
|
ENTRY(bounds)
|
|
zeroentry do_bounds
|
|
|
|
ENTRY(invalid_op)
|
|
zeroentry do_invalid_op
|
|
|
|
ENTRY(coprocessor_segment_overrun)
|
|
zeroentry do_coprocessor_segment_overrun
|
|
|
|
ENTRY(reserved)
|
|
zeroentry do_reserved
|
|
|
|
/* runs on exception stack */
|
|
ENTRY(double_fault)
|
|
CFI_STARTPROC
|
|
paranoidentry do_double_fault
|
|
jmp paranoid_exit
|
|
CFI_ENDPROC
|
|
|
|
ENTRY(invalid_TSS)
|
|
errorentry do_invalid_TSS
|
|
|
|
ENTRY(segment_not_present)
|
|
errorentry do_segment_not_present
|
|
|
|
/* runs on exception stack */
|
|
ENTRY(stack_segment)
|
|
CFI_STARTPROC
|
|
paranoidentry do_stack_segment
|
|
jmp paranoid_exit
|
|
CFI_ENDPROC
|
|
|
|
ENTRY(general_protection)
|
|
errorentry do_general_protection
|
|
|
|
ENTRY(alignment_check)
|
|
errorentry do_alignment_check
|
|
|
|
ENTRY(divide_error)
|
|
zeroentry do_divide_error
|
|
|
|
ENTRY(spurious_interrupt_bug)
|
|
zeroentry do_spurious_interrupt_bug
|
|
|
|
#ifdef CONFIG_X86_MCE
|
|
/* runs on exception stack */
|
|
ENTRY(machine_check)
|
|
CFI_STARTPROC
|
|
pushq $0
|
|
CFI_ADJUST_CFA_OFFSET 8
|
|
paranoidentry do_machine_check
|
|
jmp paranoid_exit
|
|
CFI_ENDPROC
|
|
#endif
|
|
|
|
ENTRY(call_debug)
|
|
zeroentry do_call_debug
|
|
|