*
* NOTE: This code handles signal-recognition, which happens every time
* after an interrupt and after each system call.
- *
- * Normal syscalls and interrupts don't save a full stack frame, this is
+ *
+ * Normal syscalls and interrupts don't save a full stack frame, this is
* only done for syscall tracing, signals or fork/exec et.al.
- *
- * A note on terminology:
- * - top of stack: Architecture defined interrupt frame from SS to RIP
- * at the top of the kernel process stack.
+ *
+ * A note on terminology:
+ * - top of stack: Architecture defined interrupt frame from SS to RIP
+ * at the top of the kernel process stack.
* - partial stack frame: partially saved registers upto R11.
- * - full stack frame: Like partial stack frame, but all register saved.
+ * - full stack frame: Like partial stack frame, but all register saved.
*
* Some macro usage:
* - CFI macros are used to generate dwarf2 unwind information for better
#ifndef CONFIG_PREEMPT
#define retint_kernel retint_restore_args
-#endif
+#endif
#ifdef CONFIG_PARAVIRT
ENTRY(native_usergs_sysret64)
.endm
/*
- * C code is not supposed to know about undefined top of stack. Every time
- * a C function with an pt_regs argument is called from the SYSCALL based
+ * C code is not supposed to know about undefined top of stack. Every time
+ * a C function with an pt_regs argument is called from the SYSCALL based
* fast path FIXUP_TOP_OF_STACK is needed.
* RESTORE_TOP_OF_STACK syncs the syscall state after any possible ptregs
* manipulation.
- */
-
- /* %rsp:at FRAMEEND */
+ */
+
+ /* %rsp:at FRAMEEND */
.macro FIXUP_TOP_OF_STACK tmp
movq %gs:pda_oldrsp,\tmp
movq \tmp,RSP(%rsp)
.endm
/*
* A newly forked process directly context switches into this.
- */
-/* rdi: prev */
+ */
+/* rdi: prev */
ENTRY(ret_from_fork)
CFI_DEFAULT_STACK
push kernel_eflags(%rip)
call schedule_tail
GET_THREAD_INFO(%rcx)
testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),TI_flags(%rcx)
+ CFI_REMEMBER_STATE
jnz rff_trace
-rff_action:
+rff_action:
RESTORE_REST
testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread?
je int_ret_from_sys_call
jnz int_ret_from_sys_call
RESTORE_TOP_OF_STACK %rdi,ARGOFFSET
jmp ret_from_sys_call
+ CFI_RESTORE_STATE
rff_trace:
movq %rsp,%rdi
call syscall_trace_leave
- GET_THREAD_INFO(%rcx)
+ GET_THREAD_INFO(%rcx)
jmp rff_action
CFI_ENDPROC
END(ret_from_fork)
* SYSCALL does not save anything on the stack and does not change the
* stack pointer.
*/
-
+
/*
- * Register setup:
+ * Register setup:
* rax system call number
* rdi arg0
- * rcx return address for syscall/sysret, C arg3
+ * rcx return address for syscall/sysret, C arg3
* rsi arg1
- * rdx arg2
+ * rdx arg2
* r10 arg3 (--> moved to rcx for C)
* r8 arg4
* r9 arg5
* r11 eflags for syscall/sysret, temporary for C
- * r12-r15,rbp,rbx saved by C code, not touched.
- *
+ * r12-r15,rbp,rbx saved by C code, not touched.
+ *
* Interrupts are off on entry.
* Only called from user space.
*
* When user can change the frames always force IRET. That is because
* it deals with uncanonical addresses better. SYSRET has trouble
* with them due to bugs in both AMD and Intel CPUs.
- */
+ */
ENTRY(system_call)
CFI_STARTPROC simple
*/
ENTRY(system_call_after_swapgs)
- movq %rsp,%gs:pda_oldrsp
+ movq %rsp,%gs:pda_oldrsp
movq %gs:pda_kernelstack,%rsp
/*
* No need to follow this irqs off/on section - it's straight
*/
ENABLE_INTERRUPTS(CLBR_NONE)
SAVE_ARGS 8,1
- movq %rax,ORIG_RAX-ARGOFFSET(%rsp)
+ movq %rax,ORIG_RAX-ARGOFFSET(%rsp)
movq %rcx,RIP-ARGOFFSET(%rsp)
CFI_REL_OFFSET rip,RIP-ARGOFFSET
GET_THREAD_INFO(%rcx)
movq %rax,RAX-ARGOFFSET(%rsp)
/*
* Syscall return path ending with SYSRET (fast path)
- * Has incomplete stack frame and undefined top of stack.
- */
+ * Has incomplete stack frame and undefined top of stack.
+ */
ret_from_sys_call:
movl $_TIF_ALLWORK_MASK,%edi
/* edi: flagmask */
-sysret_check:
+sysret_check:
LOCKDEP_SYS_EXIT
GET_THREAD_INFO(%rcx)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
movl TI_flags(%rcx),%edx
andl %edi,%edx
- jnz sysret_careful
+ jnz sysret_careful
CFI_REMEMBER_STATE
/*
* sysretq will re-enable interrupts:
CFI_RESTORE_STATE
/* Handle reschedules */
- /* edx: work, edi: workmask */
+ /* edx: work, edi: workmask */
sysret_careful:
bt $TIF_NEED_RESCHED,%edx
jnc sysret_signal
CFI_ADJUST_CFA_OFFSET -8
jmp sysret_check
- /* Handle a signal */
+ /* Handle a signal */
sysret_signal:
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
jmp int_with_check
-
+
badsys:
movq $-ENOSYS,RAX-ARGOFFSET(%rsp)
jmp ret_from_sys_call
#endif /* CONFIG_AUDITSYSCALL */
/* Do syscall tracing */
-tracesys:
+tracesys:
#ifdef CONFIG_AUDITSYSCALL
testl $(_TIF_WORK_SYSCALL_ENTRY & ~_TIF_SYSCALL_AUDIT),TI_flags(%rcx)
jz auditsys
call *sys_call_table(,%rax,8)
movq %rax,RAX-ARGOFFSET(%rsp)
/* Use IRET because user could have changed frame */
-
-/*
+
+/*
* Syscall return path ending with IRET.
* Has correct top of stack, but partial stack frame.
*/
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
SAVE_REST
- /* Check for syscall exit trace */
+ /* Check for syscall exit trace */
testl $_TIF_WORK_SYSCALL_EXIT,%edx
jz int_signal
pushq %rdi
CFI_ADJUST_CFA_OFFSET 8
- leaq 8(%rsp),%rdi # &ptregs -> arg1
+ leaq 8(%rsp),%rdi # &ptregs -> arg1
call syscall_trace_leave
popq %rdi
CFI_ADJUST_CFA_OFFSET -8
andl $~(_TIF_WORK_SYSCALL_EXIT|_TIF_SYSCALL_EMU),%edi
jmp int_restore_rest
-
+
int_signal:
testl $_TIF_DO_NOTIFY_MASK,%edx
jz 1f
jmp int_with_check
CFI_ENDPROC
END(system_call)
-
-/*
+
+/*
* Certain special system calls that need to save a complete full stack frame.
- */
-
+ */
+
.macro PTREGSCALL label,func,arg
.globl \label
\label:
ret
CFI_ENDPROC
END(ptregscall_common)
-
+
ENTRY(stub_execve)
CFI_STARTPROC
popq %r11
jmp int_ret_from_sys_call
CFI_ENDPROC
END(stub_execve)
-
+
/*
* sigreturn is special because it needs to restore all registers on return.
* This cannot be done with SYSRET, so use the IRET return path instead.
- */
+ */
ENTRY(stub_rt_sigreturn)
CFI_STARTPROC
addq $8, %rsp
GET_THREAD_INFO(%rcx)
testl $3,CS-ARGOFFSET(%rsp)
je retint_kernel
-
+
/* Interrupt came from user space */
/*
* Has a correct top of stack, but a partial stack frame
* %rcx: thread info. Interrupts off.
- */
+ */
retint_with_reschedule:
movl $_TIF_WORK_MASK,%edi
retint_check:
pushq %rdi
CFI_ADJUST_CFA_OFFSET 8
call schedule
- popq %rdi
+ popq %rdi
CFI_ADJUST_CFA_OFFSET -8
GET_THREAD_INFO(%rcx)
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
jmp retint_check
-
+
retint_signal:
testl $_TIF_DO_NOTIFY_MASK,%edx
jz retint_swapgs
TRACE_IRQS_ON
ENABLE_INTERRUPTS(CLBR_NONE)
SAVE_REST
- movq $-1,ORIG_RAX(%rsp)
+ movq $-1,ORIG_RAX(%rsp)
xorl %esi,%esi # oldset
movq %rsp,%rdi # &pt_regs
call do_notify_resume
jnc retint_restore_args
call preempt_schedule_irq
jmp exit_intr
-#endif
+#endif
CFI_ENDPROC
END(common_interrupt)
-
+
/*
* APIC interrupts.
- */
+ */
.macro apicinterrupt num,func
INTR_FRAME
pushq $~(\num)
apicinterrupt THRESHOLD_APIC_VECTOR,mce_threshold_interrupt
END(threshold_interrupt)
-#ifdef CONFIG_SMP
+#ifdef CONFIG_SMP
ENTRY(reschedule_interrupt)
apicinterrupt RESCHEDULE_VECTOR,smp_reschedule_interrupt
END(reschedule_interrupt)
.macro INVALIDATE_ENTRY num
ENTRY(invalidate_interrupt\num)
- apicinterrupt INVALIDATE_TLB_VECTOR_START+\num,smp_invalidate_interrupt
+ apicinterrupt INVALIDATE_TLB_VECTOR_START+\num,smp_invalidate_interrupt
END(invalidate_interrupt\num)
.endm
ENTRY(spurious_interrupt)
apicinterrupt SPURIOUS_APIC_VECTOR,smp_spurious_interrupt
END(spurious_interrupt)
-
+
/*
* Exception entry points.
- */
+ */
.macro zeroentry sym
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
- pushq $0 /* push error code/oldrax */
+ pushq $0 /* push error code/oldrax */
CFI_ADJUST_CFA_OFFSET 8
- pushq %rax /* push real oldrax to the rdi slot */
+ pushq %rax /* push real oldrax to the rdi slot */
CFI_ADJUST_CFA_OFFSET 8
CFI_REL_OFFSET rax,0
leaq \sym(%rip),%rax
jmp error_entry
CFI_ENDPROC
- .endm
+ .endm
.macro errorentry sym
XCPT_FRAME
/*
* Exception entry point. This expects an error code/orig_rax on the stack
- * and the exception handler in %rax.
- */
+ * and the exception handler in %rax.
+ */
KPROBE_ENTRY(error_entry)
_frame RDI
CFI_REL_OFFSET rax,0
/* rdi slot contains rax, oldrax contains error code */
- cld
+ cld
subq $14*8,%rsp
CFI_ADJUST_CFA_OFFSET (14*8)
movq %rsi,13*8(%rsp)
CFI_REL_OFFSET rdx,RDX
movq %rcx,11*8(%rsp)
CFI_REL_OFFSET rcx,RCX
- movq %rsi,10*8(%rsp) /* store rax */
+ movq %rsi,10*8(%rsp) /* store rax */
CFI_REL_OFFSET rax,RAX
movq %r8, 9*8(%rsp)
CFI_REL_OFFSET r8,R8
CFI_REL_OFFSET r10,R10
movq %r11,6*8(%rsp)
CFI_REL_OFFSET r11,R11
- movq %rbx,5*8(%rsp)
+ movq %rbx,5*8(%rsp)
CFI_REL_OFFSET rbx,RBX
- movq %rbp,4*8(%rsp)
+ movq %rbp,4*8(%rsp)
CFI_REL_OFFSET rbp,RBP
- movq %r12,3*8(%rsp)
+ movq %r12,3*8(%rsp)
CFI_REL_OFFSET r12,R12
- movq %r13,2*8(%rsp)
+ movq %r13,2*8(%rsp)
CFI_REL_OFFSET r13,R13
- movq %r14,1*8(%rsp)
+ movq %r14,1*8(%rsp)
CFI_REL_OFFSET r14,R14
- movq %r15,(%rsp)
+ movq %r15,(%rsp)
CFI_REL_OFFSET r15,R15
- xorl %ebx,%ebx
+ xorl %ebx,%ebx
testl $3,CS(%rsp)
je error_kernelspace
-error_swapgs:
+error_swapgs:
SWAPGS
error_sti:
TRACE_IRQS_OFF
- movq %rdi,RDI(%rsp)
+ movq %rdi,RDI(%rsp)
CFI_REL_OFFSET rdi,RDI
movq %rsp,%rdi
- movq ORIG_RAX(%rsp),%rsi /* get error code */
+ 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) */
RESTORE_REST
DISABLE_INTERRUPTS(CLBR_NONE)
TRACE_IRQS_OFF
- GET_THREAD_INFO(%rcx)
+ GET_THREAD_INFO(%rcx)
testl %eax,%eax
jne retint_kernel
LOCKDEP_SYS_EXIT_IRQ
/* 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
+ B stepping K8s sometimes report an truncated RIP for IRET
exceptions returning to compat mode. Check for these here too. */
leaq irq_return(%rip),%rcx
cmpq %rcx,RIP(%rsp)
je error_swapgs
jmp error_sti
KPROBE_END(error_entry)
-
+
/* Reload gs selector with exception handling */
- /* edi: new selector */
+ /* edi: new selector */
ENTRY(native_load_gs_index)
CFI_STARTPROC
pushf
CFI_ADJUST_CFA_OFFSET 8
DISABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI))
SWAPGS
-gs_change:
- movl %edi,%gs
+gs_change:
+ movl %edi,%gs
2: mfence /* workaround */
SWAPGS
popf
ret
CFI_ENDPROC
ENDPROC(native_load_gs_index)
-
+
.section __ex_table,"a"
.align 8
.quad gs_change,bad_gs
.previous
.section .fixup,"ax"
/* running with kernelgs */
-bad_gs:
+bad_gs:
SWAPGS /* switch back to user gs */
xorl %eax,%eax
movl %eax,%gs
jmp 2b
- .previous
-
+ .previous
+
/*
* Create a kernel thread.
*
xorl %r8d,%r8d
xorl %r9d,%r9d
-
+
# clone now
call do_fork
movq %rax,RAX(%rsp)
* 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]
+ * [Hopefully no generic code relies on the reschedule -AK]
*/
RESTORE_ALL
UNFAKE_STACK_FRAME
ret
CFI_ENDPROC
ENDPROC(kernel_thread)
-
+
child_rip:
pushq $0 # fake return address
CFI_STARTPROC
# exit
mov %eax, %edi
call do_exit
+ ud2 # padding for call trace
CFI_ENDPROC
ENDPROC(child_rip)
ENTRY(kernel_execve)
CFI_STARTPROC
FAKE_STACK_FRAME $0
- SAVE_ALL
+ SAVE_ALL
movq %rsp,%rcx
call sys_execve
- movq %rax, RAX(%rsp)
+ movq %rax, RAX(%rsp)
RESTORE_REST
testq %rax,%rax
je int_ret_from_sys_call
END(coprocessor_error)
ENTRY(simd_coprocessor_error)
- zeroentry do_simd_coprocessor_error
+ zeroentry do_simd_coprocessor_error
END(simd_coprocessor_error)
ENTRY(device_not_available)
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
pushq $0
- CFI_ADJUST_CFA_OFFSET 8
+ CFI_ADJUST_CFA_OFFSET 8
paranoidentry do_debug, DEBUG_STACK
paranoidexit
KPROBE_END(debug)
- /* runs on exception stack */
+ /* runs on exception stack */
KPROBE_ENTRY(nmi)
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
END(bounds)
ENTRY(invalid_op)
- zeroentry do_invalid_op
+ zeroentry do_invalid_op
END(invalid_op)
ENTRY(coprocessor_segment_overrun)
INTR_FRAME
PARAVIRT_ADJUST_EXCEPTION_FRAME
pushq $0
- CFI_ADJUST_CFA_OFFSET 8
+ CFI_ADJUST_CFA_OFFSET 8
paranoidentry do_machine_check
jmp paranoid_exit1
CFI_ENDPROC
Code Review / linux-2.6.git / blobdiff