x86, um: convert to saner kernel_execve() semantics
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index fe4cc30..91d2959 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -298,12 +298,20 @@
CFI_ENDPROC
END(ret_from_fork)
-ENTRY(ret_from_kernel_execve)
- movl %eax, %esp
- movl $0,PT_EAX(%esp)
+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
-END(ret_from_kernel_execve)
+ CFI_ENDPROC
+ENDPROC(ret_from_kernel_thread)
/*
* Interrupt exit functions should be protected against kprobes
@@ -994,21 +1002,6 @@
*/
.popsection
-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)
- call do_exit
- ud2 # padding for call trace
- CFI_ENDPROC
-ENDPROC(ret_from_kernel_thread)
-
#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. */
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 053c955..e1f98c2 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -459,15 +459,13 @@
jmp ret_from_sys_call # go to the SYSRET fastpath
1:
- subq $REST_SKIP, %rsp # move the stack pointer back
+ subq $REST_SKIP, %rsp # leave space for volatiles
CFI_ADJUST_CFA_OFFSET REST_SKIP
movq %rbp, %rdi
call *%rbx
- # exit
- mov %eax, %edi
- call do_exit
- ud2 # padding for call trace
-
+ movl $0, RAX(%rsp)
+ RESTORE_REST
+ jmp int_ret_from_sys_call
CFI_ENDPROC
END(ret_from_fork)
@@ -1214,20 +1212,6 @@
jmp 2b
.previous
-ENTRY(ret_from_kernel_execve)
- movq %rdi, %rsp
- movl $0, RAX(%rsp)
- // RESTORE_REST
- movq 0*8(%rsp), %r15
- movq 1*8(%rsp), %r14
- movq 2*8(%rsp), %r13
- movq 3*8(%rsp), %r12
- movq 4*8(%rsp), %rbp
- movq 5*8(%rsp), %rbx
- addq $(6*8), %rsp
- jmp int_ret_from_sys_call
-END(ret_from_kernel_execve)
-
/* Call softirq on interrupt stack. Interrupts are off. */
ENTRY(call_softirq)
CFI_STARTPROC