diff options
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 31 |
1 files changed, 16 insertions, 15 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index e41734a537b..3194636a429 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -361,34 +361,35 @@ ENTRY(save_paranoid) END(save_paranoid) /* - * A newly forked process directly context switches into this. + * A newly forked process directly context switches into this address. + * + * rdi: prev task we switched from */ -/* rdi: prev */ ENTRY(ret_from_fork) DEFAULT_FRAME + push kernel_eflags(%rip) CFI_ADJUST_CFA_OFFSET 8 - popf # reset kernel eflags + popf # reset kernel eflags CFI_ADJUST_CFA_OFFSET -8 - call schedule_tail + + call schedule_tail # rdi: 'prev' task parameter + GET_THREAD_INFO(%rcx) - testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT),TI_flags(%rcx) + CFI_REMEMBER_STATE - jnz rff_trace -rff_action: RESTORE_REST - testl $3,CS-ARGOFFSET(%rsp) # from kernel_thread? + + testl $3, CS-ARGOFFSET(%rsp) # from kernel_thread? je int_ret_from_sys_call - testl $_TIF_IA32,TI_flags(%rcx) + + testl $_TIF_IA32, TI_flags(%rcx) # 32-bit compat task needs IRET jnz int_ret_from_sys_call + RESTORE_TOP_OF_STACK %rdi, -ARGOFFSET - jmp ret_from_sys_call + jmp ret_from_sys_call # go to the SYSRET fastpath + CFI_RESTORE_STATE -rff_trace: - movq %rsp,%rdi - call syscall_trace_leave - GET_THREAD_INFO(%rcx) - jmp rff_action CFI_ENDPROC END(ret_from_fork) |