s390: switch to saner kernel_execve() semantics
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index ef46f66..aa8f2ba 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -330,40 +330,18 @@
la %r11,STACK_FRAME_OVERHEAD(%r15)
l %r12,__LC_THREAD_INFO
l %r13,__LC_SVC_NEW_PSW+4
+ l %r1,BASED(.Lschedule_tail)
+ basr %r14,%r1 # call schedule_tail
+ TRACE_IRQS_ON
+ ssm __LC_SVC_NEW_PSW # reenable interrupts
tm __PT_PSW+1(%r11),0x01 # forking a kernel thread ?
- je 1f
- l %r1,BASED(.Lschedule_tail)
- basr %r14,%r1 # call schedule_tail
- TRACE_IRQS_ON
- ssm __LC_SVC_NEW_PSW # reenable interrupts
- j sysc_tracenogo
-
-1: # it's a kernel thread
- st %r15,__PT_R15(%r11) # store stack pointer for new kthread
- l %r1,BASED(.Lschedule_tail)
- basr %r14,%r1 # call schedule_tail
- TRACE_IRQS_ON
- ssm __LC_SVC_NEW_PSW # reenable interrupts
- lm %r9,%r11,__PT_R9(%r11) # load gprs
+ jne sysc_tracenogo
+ # it's a kernel thread
+ lm %r9,%r10,__PT_R9(%r11) # load gprs
ENTRY(kernel_thread_starter)
la %r2,0(%r10)
basr %r14,%r9
- la %r2,0
- br %r11 # do_exit
-
-#
-# kernel_execve function needs to deal with pt_regs that is not
-# at the usual place
-#
-ENTRY(ret_from_kernel_execve)
- ssm __LC_PGM_NEW_PSW # disable I/O and ext. interrupts
- lr %r15,%r2
- lr %r11,%r2
- ahi %r15,-STACK_FRAME_OVERHEAD
- xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
- l %r12,__LC_THREAD_INFO
- ssm __LC_SVC_NEW_PSW # reenable interrupts
- j sysc_return
+ j sysc_tracenogo
/*
* Program check handler routine