* - CFI macros are used to generate dwarf2 unwind information for better
* backtraces. They don't change any code.
* - ENTRY/END Define functions in the symbol table.
- * - FIXUP_TOP_OF_STACK/RESTORE_TOP_OF_STACK - Fix up the hardware stack
- * frame that is otherwise undefined after a SYSCALL
* - TRACE_IRQ_* - Trace hard interrupt state for lock debugging.
* - idtentry - Define exception entry points.
*/
#endif
/*
- * C code is not supposed to know that the iret frame is not populated.
- * 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.
- */
- .macro FIXUP_TOP_OF_STACK tmp offset=0
- /* copy flags to r11 as sysret would do */
- movq EFLAGS+\offset(%rsp),\tmp
- movq \tmp,R11+\offset(%rsp)
- .endm
-
- .macro RESTORE_TOP_OF_STACK tmp offset=0
- /* nothing to do */
- .endm
-
-/*
* empty frame
*/
.macro EMPTY_FRAME start=1 offset=0
pushq_cfi_reg r8 /* pt_regs->r8 */
pushq_cfi_reg r9 /* pt_regs->r9 */
pushq_cfi_reg r10 /* pt_regs->r10 */
- sub $(7*8),%rsp /* pt_regs->r11,bp,bx,r12-15 not saved */
+ pushq_cfi_reg r11 /* pt_regs->r11 */
+ sub $(6*8),%rsp /* pt_regs->bp,bx,r12-15 not saved */
testl $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,SIZEOF_PTREGS)
jnz tracesys
CFI_RESTORE_STATE
int_ret_from_sys_call_fixup:
- FIXUP_TOP_OF_STACK %r11
jmp int_ret_from_sys_call
/* Do syscall entry tracing */
tracesys_phase2:
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %rdi
movq %rsp, %rdi
movq $AUDIT_ARCH_X86_64, %rsi
movq %rax,%rdx
CFI_STARTPROC
DEFAULT_FRAME 0, 8 /* offset 8: return address */
SAVE_EXTRA_REGS 8
- FIXUP_TOP_OF_STACK %r11, 8
call sys_\func
- RESTORE_TOP_OF_STACK %r11, 8
ret
CFI_ENDPROC
END(stub_\func)
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call sys_execve
movq %rax,RAX(%rsp)
RESTORE_EXTRA_REGS
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call sys_execveat
- RESTORE_TOP_OF_STACK %r11
movq %rax,RAX(%rsp)
RESTORE_EXTRA_REGS
jmp int_ret_from_sys_call
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call sys_rt_sigreturn
movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer
RESTORE_EXTRA_REGS
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call sys32_x32_rt_sigreturn
movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer
RESTORE_EXTRA_REGS
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call compat_sys_execve
- RESTORE_TOP_OF_STACK %r11
movq %rax,RAX(%rsp)
RESTORE_EXTRA_REGS
jmp int_ret_from_sys_call
addq $8, %rsp
DEFAULT_FRAME 0
SAVE_EXTRA_REGS
- FIXUP_TOP_OF_STACK %r11
call compat_sys_execveat
- RESTORE_TOP_OF_STACK %r11
movq %rax,RAX(%rsp)
RESTORE_EXTRA_REGS
jmp int_ret_from_sys_call