1 files changed, 109 insertions, 103 deletions

diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S
index 68d1a02db6be..af8bd3b90a26 100644
--- a/arch/s390/kernel/entry.S
+++ b/arch/s390/kernel/entry.S
@@ -9,7 +9,6 @@
  *               Heiko Carstens <heiko.carstens@de.ibm.com>
  */
 
-#include <linux/sys.h>
 #include <linux/linkage.h>
 #include <linux/init.h>
 #include <asm/cache.h>
@@ -110,31 +109,36 @@ STACK_SIZE  = 1 << STACK_SHIFT
 1:      stm     %r10,%r11,\lc_sum
         .endm
 
-        .macro  SAVE_ALL_BASE savearea
+        .macro  SAVE_ALL_SVC psworg,savearea
         stm     %r12,%r15,\savearea
         l       %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
+        l       %r15,__LC_KERNEL_STACK  # problem state -> load ksp
+        s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
         .endm
 
-        .macro  SAVE_ALL_SVC psworg,savearea
-        la      %r12,\psworg
-        l       %r15,__LC_KERNEL_STACK  # problem state -> load ksp
+        .macro  SAVE_ALL_BASE savearea
+        stm     %r12,%r15,\savearea
+        l       %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
         .endm
 
-        .macro  SAVE_ALL_SYNC psworg,savearea
-        la      %r12,\psworg
+        .macro  SAVE_ALL_PGM psworg,savearea
         tm      \psworg+1,0x01          # test problem state bit
-        bz      BASED(2f)               # skip stack setup save
-        l       %r15,__LC_KERNEL_STACK  # problem state -> load ksp
 #ifdef CONFIG_CHECK_STACK
-        b       BASED(3f)
-2:      tml     %r15,STACK_SIZE - CONFIG_STACK_GUARD
-        bz      BASED(stack_overflow)
-3:
+        bnz     BASED(1f)
+        tml     %r15,STACK_SIZE - CONFIG_STACK_GUARD
+        bnz     BASED(2f)
+        la      %r12,\psworg
+        b       BASED(stack_overflow)
+#else
+        bz      BASED(2f)
 #endif
-2:
+1:      l       %r15,__LC_KERNEL_STACK  # problem state -> load ksp
+2:      s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
         .endm
 
         .macro  SAVE_ALL_ASYNC psworg,savearea
+        stm     %r12,%r15,\savearea
+        l       %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
         la      %r12,\psworg
         tm      \psworg+1,0x01          # test problem state bit
         bnz     BASED(1f)               # from user -> load async stack
@@ -149,27 +153,23 @@ STACK_SIZE  = 1 << STACK_SHIFT
 0:      l       %r14,__LC_ASYNC_STACK   # are we already on the async stack ?
         slr     %r14,%r15
         sra     %r14,STACK_SHIFT
-        be      BASED(2f)
-1:      l       %r15,__LC_ASYNC_STACK
 #ifdef CONFIG_CHECK_STACK
-        b       BASED(3f)
-2:      tml     %r15,STACK_SIZE - CONFIG_STACK_GUARD
-        bz      BASED(stack_overflow)
-3:
+        bnz     BASED(1f)
+        tml     %r15,STACK_SIZE - CONFIG_STACK_GUARD
+        bnz     BASED(2f)
+        b       BASED(stack_overflow)
+#else
+        bz      BASED(2f)
 #endif
-2:
+1:      l       %r15,__LC_ASYNC_STACK
+2:      s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
         .endm
 
-        .macro  CREATE_STACK_FRAME psworg,savearea
-        s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
-        mvc     SP_PSW(8,%r15),0(%r12)  # move user PSW to stack
+        .macro  CREATE_STACK_FRAME savearea
+        xc      __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
         st      %r2,SP_ORIG_R2(%r15)    # store original content of gpr 2
-        icm     %r12,12,__LC_SVC_ILC
-        stm     %r0,%r11,SP_R0(%r15)    # store gprs %r0-%r11 to kernel stack
-        st      %r12,SP_ILC(%r15)
         mvc     SP_R12(16,%r15),\savearea # move %r12-%r15 to stack
-        la      %r12,0
-        st      %r12,__SF_BACKCHAIN(%r15)       # clear back chain
+        stm     %r0,%r11,SP_R0(%r15)    # store gprs %r0-%r11 to kernel stack
         .endm
 
         .macro  RESTORE_ALL psworg,sync
@@ -237,10 +237,11 @@ __critical_start:
 system_call:
         stpt    __LC_SYNC_ENTER_TIMER
 sysc_saveall:
-        SAVE_ALL_BASE __LC_SAVE_AREA
         SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
-        CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
-        lh      %r7,0x8a          # get svc number from lowcore
+        CREATE_STACK_FRAME __LC_SAVE_AREA
+        mvc     SP_PSW(8,%r15),__LC_SVC_OLD_PSW
+        mvc     SP_ILC(4,%r15),__LC_SVC_ILC
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
 sysc_vtime:
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
 sysc_stime:
@@ -248,20 +249,20 @@ sysc_stime:
 sysc_update:
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 sysc_do_svc:
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
-        ltr     %r7,%r7                 # test for svc 0
+        xr      %r7,%r7
+        icm     %r7,3,SP_SVCNR(%r15)    # load svc number and test for svc 0
         bnz     BASED(sysc_nr_ok)       # svc number > 0
         # svc 0: system call number in %r1
         cl      %r1,BASED(.Lnr_syscalls)
         bnl     BASED(sysc_nr_ok)
+        sth     %r1,SP_SVCNR(%r15)
         lr      %r7,%r1           # copy svc number to %r7
 sysc_nr_ok:
-        sth     %r7,SP_SVCNR(%r15)
         sll     %r7,2             # svc number *4
-        l       %r8,BASED(.Lsysc_table)
-        tm      __TI_flags+2(%r9),_TIF_SYSCALL
+        l       %r10,BASED(.Lsysc_table)
+        tm      __TI_flags+2(%r12),_TIF_SYSCALL
         mvc     SP_ARGS(4,%r15),SP_R7(%r15)
-        l       %r8,0(%r7,%r8)    # get system call addr.
+        l       %r8,0(%r7,%r10)   # get system call addr.
         bnz     BASED(sysc_tracesys)
         basr    %r14,%r8          # call sys_xxxx
         st      %r2,SP_R2(%r15)   # store return value (change R2 on stack)
@@ -269,7 +270,7 @@ sysc_nr_ok:
 sysc_return:
         LOCKDEP_SYS_EXIT
 sysc_tif:
-        tm      __TI_flags+3(%r9),_TIF_WORK_SVC
+        tm      __TI_flags+3(%r12),_TIF_WORK_SVC
         bnz     BASED(sysc_work)  # there is work to do (signals etc.)
 sysc_restore:
         RESTORE_ALL __LC_RETURN_PSW,1
@@ -286,17 +287,17 @@ sysc_work:
 # One of the work bits is on. Find out which one.
 #
 sysc_work_tif:
-        tm      __TI_flags+3(%r9),_TIF_MCCK_PENDING
+        tm      __TI_flags+3(%r12),_TIF_MCCK_PENDING
         bo      BASED(sysc_mcck_pending)
-        tm      __TI_flags+3(%r9),_TIF_NEED_RESCHED
+        tm      __TI_flags+3(%r12),_TIF_NEED_RESCHED
         bo      BASED(sysc_reschedule)
-        tm      __TI_flags+3(%r9),_TIF_SIGPENDING
+        tm      __TI_flags+3(%r12),_TIF_SIGPENDING
         bo      BASED(sysc_sigpending)
-        tm      __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+        tm      __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
         bo      BASED(sysc_notify_resume)
-        tm      __TI_flags+3(%r9),_TIF_RESTART_SVC
+        tm      __TI_flags+3(%r12),_TIF_RESTART_SVC
         bo      BASED(sysc_restart)
-        tm      __TI_flags+3(%r9),_TIF_SINGLE_STEP
+        tm      __TI_flags+3(%r12),_TIF_SINGLE_STEP
         bo      BASED(sysc_singlestep)
         b       BASED(sysc_return)      # beware of critical section cleanup
 
@@ -320,13 +321,13 @@ sysc_mcck_pending:
 # _TIF_SIGPENDING is set, call do_signal
 #
 sysc_sigpending:
-        ni      __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+        ni      __TI_flags+3(%r12),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
         l       %r1,BASED(.Ldo_signal)
         basr    %r14,%r1                # call do_signal
-        tm      __TI_flags+3(%r9),_TIF_RESTART_SVC
+        tm      __TI_flags+3(%r12),_TIF_RESTART_SVC
         bo      BASED(sysc_restart)
-        tm      __TI_flags+3(%r9),_TIF_SINGLE_STEP
+        tm      __TI_flags+3(%r12),_TIF_SINGLE_STEP
         bo      BASED(sysc_singlestep)
         b       BASED(sysc_return)
 
@@ -344,19 +345,19 @@ sysc_notify_resume:
 # _TIF_RESTART_SVC is set, set up registers and restart svc
 #
 sysc_restart:
-        ni      __TI_flags+3(%r9),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
+        ni      __TI_flags+3(%r12),255-_TIF_RESTART_SVC # clear TIF_RESTART_SVC
         l       %r7,SP_R2(%r15)         # load new svc number
         mvc     SP_R2(4,%r15),SP_ORIG_R2(%r15) # restore first argument
         lm      %r2,%r6,SP_R2(%r15)     # load svc arguments
+        sth     %r7,SP_SVCNR(%r15)
         b       BASED(sysc_nr_ok)       # restart svc
 
 #
 # _TIF_SINGLE_STEP is set, call do_single_step
 #
 sysc_singlestep:
-        ni      __TI_flags+3(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
-        mvi     SP_SVCNR(%r15),0xff     # set trap indication to pgm check
-        mvi     SP_SVCNR+1(%r15),0xff
+        ni      __TI_flags+3(%r12),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
+        xc      SP_SVCNR(2,%r15),SP_SVCNR(%r15)         # clear svc number
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         l       %r1,BASED(.Lhandle_per) # load adr. of per handler
         la      %r14,BASED(sysc_return) # load adr. of system return
@@ -370,15 +371,15 @@ sysc_tracesys:
         l       %r1,BASED(.Ltrace_entry)
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
         la      %r3,0
-        srl     %r7,2
-        st      %r7,SP_R2(%r15)
+        xr      %r0,%r0
+        icm     %r0,3,SP_SVCNR(%r15)
+        st      %r0,SP_R2(%r15)
         basr    %r14,%r1
         cl      %r2,BASED(.Lnr_syscalls)
         bnl     BASED(sysc_tracenogo)
-        l       %r8,BASED(.Lsysc_table)
         lr      %r7,%r2
         sll     %r7,2                   # svc number *4
-        l       %r8,0(%r7,%r8)
+        l       %r8,0(%r7,%r10)
 sysc_tracego:
         lm      %r3,%r6,SP_R3(%r15)
         mvc     SP_ARGS(4,%r15),SP_R7(%r15)
@@ -386,7 +387,7 @@ sysc_tracego:
         basr    %r14,%r8                # call sys_xxx
         st      %r2,SP_R2(%r15)         # store return value
 sysc_tracenogo:
-        tm      __TI_flags+2(%r9),_TIF_SYSCALL
+        tm      __TI_flags+2(%r12),_TIF_SYSCALL
         bz      BASED(sysc_return)
         l       %r1,BASED(.Ltrace_exit)
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
@@ -399,7 +400,7 @@ sysc_tracenogo:
         .globl  ret_from_fork
 ret_from_fork:
         l       %r13,__LC_SVC_NEW_PSW+4
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      SP_PSW+1(%r15),0x01     # forking a kernel thread ?
         bo      BASED(0f)
         st      %r15,SP_R15(%r15)       # store stack pointer for new kthread
@@ -434,8 +435,8 @@ kernel_execve:
 0:      stnsm   __SF_EMPTY(%r15),0xfc   # disable interrupts
         l       %r15,__LC_KERNEL_STACK  # load ksp
         s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
-        l       %r9,__LC_THREAD_INFO
         mvc     SP_PTREGS(__PT_SIZE,%r15),0(%r12)       # copy pt_regs
+        l       %r12,__LC_THREAD_INFO
         xc      __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15)
         stosm   __SF_EMPTY(%r15),0x03   # reenable interrupts
         l       %r1,BASED(.Lexecve_tail)
@@ -465,26 +466,27 @@ pgm_check_handler:
         SAVE_ALL_BASE __LC_SAVE_AREA
         tm      __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
         bnz     BASED(pgm_per)          # got per exception -> special case
-        SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
-        CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
+        SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
+        CREATE_STACK_FRAME __LC_SAVE_AREA
+        xc      SP_ILC(4,%r15),SP_ILC(%r15)
+        mvc     SP_PSW(8,%r15),__LC_PGM_OLD_PSW
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      SP_PSW+1(%r15),0x01     # interrupting from user ?
         bz      BASED(pgm_no_vtime)
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 pgm_no_vtime:
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         l       %r3,__LC_PGM_ILC        # load program interruption code
         l       %r4,__LC_TRANS_EXC_CODE
         REENABLE_IRQS
         la      %r8,0x7f
         nr      %r8,%r3
-pgm_do_call:
-        l       %r7,BASED(.Ljump_table)
         sll     %r8,2
-        l       %r7,0(%r8,%r7)          # load address of handler routine
+        l       %r1,BASED(.Ljump_table)
+        l       %r1,0(%r8,%r1)          # load address of handler routine
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
-        basr    %r14,%r7                # branch to interrupt-handler
+        basr    %r14,%r1                # branch to interrupt-handler
 pgm_exit:
         b       BASED(sysc_return)
 
@@ -505,33 +507,34 @@ pgm_per:
 # Normal per exception
 #
 pgm_per_std:
-        SAVE_ALL_SYNC __LC_PGM_OLD_PSW,__LC_SAVE_AREA
-        CREATE_STACK_FRAME __LC_PGM_OLD_PSW,__LC_SAVE_AREA
+        SAVE_ALL_PGM __LC_PGM_OLD_PSW,__LC_SAVE_AREA
+        CREATE_STACK_FRAME __LC_SAVE_AREA
+        mvc     SP_PSW(8,%r15),__LC_PGM_OLD_PSW
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      SP_PSW+1(%r15),0x01     # interrupting from user ?
         bz      BASED(pgm_no_vtime2)
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
 pgm_no_vtime2:
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
-        l       %r1,__TI_task(%r9)
+        l       %r1,__TI_task(%r12)
         tm      SP_PSW+1(%r15),0x01     # kernel per event ?
         bz      BASED(kernel_per)
         mvc     __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID
         mvc     __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS
         mvc     __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID
-        oi      __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+        oi      __TI_flags+3(%r12),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
         l       %r3,__LC_PGM_ILC        # load program interruption code
         l       %r4,__LC_TRANS_EXC_CODE
         REENABLE_IRQS
         la      %r8,0x7f
         nr      %r8,%r3                 # clear per-event-bit and ilc
         be      BASED(pgm_exit2)        # only per or per+check ?
-        l       %r7,BASED(.Ljump_table)
         sll     %r8,2
-        l       %r7,0(%r8,%r7)          # load address of handler routine
+        l       %r1,BASED(.Ljump_table)
+        l       %r1,0(%r8,%r1)          # load address of handler routine
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
-        basr    %r14,%r7                # branch to interrupt-handler
+        basr    %r14,%r1                # branch to interrupt-handler
 pgm_exit2:
         b       BASED(sysc_return)
 
@@ -539,18 +542,19 @@ pgm_exit2:
 # it was a single stepped SVC that is causing all the trouble
 #
 pgm_svcper:
-        SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
-        CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
+        SAVE_ALL_PGM __LC_SVC_OLD_PSW,__LC_SAVE_AREA
+        CREATE_STACK_FRAME __LC_SAVE_AREA
+        mvc     SP_PSW(8,%r15),__LC_SVC_OLD_PSW
+        mvc     SP_ILC(4,%r15),__LC_SVC_ILC
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_SYNC_ENTER_TIMER,__LC_USER_TIMER
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
-        lh      %r7,0x8a                # get svc number from lowcore
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
-        l       %r8,__TI_task(%r9)
+        l       %r8,__TI_task(%r12)
         mvc     __THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
         mvc     __THREAD_per+__PER_address(4,%r8),__LC_PER_ADDRESS
         mvc     __THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
-        oi      __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
+        oi      __TI_flags+3(%r12),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
         stosm   __SF_EMPTY(%r15),0x03   # reenable interrupts
         lm      %r2,%r6,SP_R2(%r15)     # load svc arguments
         b       BASED(sysc_do_svc)
@@ -560,8 +564,7 @@ pgm_svcper:
 #
 kernel_per:
         REENABLE_IRQS
-        mvi     SP_SVCNR(%r15),0xff     # set trap indication to pgm check
-        mvi     SP_SVCNR+1(%r15),0xff
+        xc      SP_SVCNR(2,%r15),SP_SVCNR(%r15)
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         l       %r1,BASED(.Lhandle_per) # load adr. of per handler
         basr    %r14,%r1                # branch to do_single_step
@@ -575,9 +578,10 @@ kernel_per:
 io_int_handler:
         stck    __LC_INT_CLOCK
         stpt    __LC_ASYNC_ENTER_TIMER
-        SAVE_ALL_BASE __LC_SAVE_AREA+16
         SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
-        CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+16
+        CREATE_STACK_FRAME __LC_SAVE_AREA+16
+        mvc     SP_PSW(8,%r15),0(%r12)  # move user PSW to stack
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      SP_PSW+1(%r15),0x01     # interrupting from user ?
         bz      BASED(io_no_vtime)
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
@@ -585,7 +589,6 @@ io_int_handler:
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 io_no_vtime:
         TRACE_IRQS_OFF
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         l       %r1,BASED(.Ldo_IRQ)     # load address of do_IRQ
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         basr    %r14,%r1                # branch to standard irq handler
@@ -593,7 +596,7 @@ io_return:
         LOCKDEP_SYS_EXIT
         TRACE_IRQS_ON
 io_tif:
-        tm      __TI_flags+3(%r9),_TIF_WORK_INT
+        tm      __TI_flags+3(%r12),_TIF_WORK_INT
         bnz     BASED(io_work)          # there is work to do (signals etc.)
 io_restore:
         RESTORE_ALL __LC_RETURN_PSW,0
@@ -611,9 +614,9 @@ io_work:
         bo      BASED(io_work_user)     # yes -> do resched & signal
 #ifdef CONFIG_PREEMPT
         # check for preemptive scheduling
-        icm     %r0,15,__TI_precount(%r9)
+        icm     %r0,15,__TI_precount(%r12)
         bnz     BASED(io_restore)       # preemption disabled
-        tm      __TI_flags+3(%r9),_TIF_NEED_RESCHED
+        tm      __TI_flags+3(%r12),_TIF_NEED_RESCHED
         bno     BASED(io_restore)
         # switch to kernel stack
         l       %r1,SP_R15(%r15)
@@ -647,13 +650,13 @@ io_work_user:
 #               and _TIF_MCCK_PENDING
 #
 io_work_tif:
-        tm      __TI_flags+3(%r9),_TIF_MCCK_PENDING
+        tm      __TI_flags+3(%r12),_TIF_MCCK_PENDING
         bo      BASED(io_mcck_pending)
-        tm      __TI_flags+3(%r9),_TIF_NEED_RESCHED
+        tm      __TI_flags+3(%r12),_TIF_NEED_RESCHED
         bo      BASED(io_reschedule)
-        tm      __TI_flags+3(%r9),_TIF_SIGPENDING
+        tm      __TI_flags+3(%r12),_TIF_SIGPENDING
         bo      BASED(io_sigpending)
-        tm      __TI_flags+3(%r9),_TIF_NOTIFY_RESUME
+        tm      __TI_flags+3(%r12),_TIF_NOTIFY_RESUME
         bo      BASED(io_notify_resume)
         b       BASED(io_return)        # beware of critical section cleanup
 
@@ -713,16 +716,16 @@ io_notify_resume:
 ext_int_handler:
         stck    __LC_INT_CLOCK
         stpt    __LC_ASYNC_ENTER_TIMER
-        SAVE_ALL_BASE __LC_SAVE_AREA+16
         SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
-        CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+16
+        CREATE_STACK_FRAME __LC_SAVE_AREA+16
+        mvc     SP_PSW(8,%r15),0(%r12)  # move user PSW to stack
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      SP_PSW+1(%r15),0x01     # interrupting from user ?
         bz      BASED(ext_no_vtime)
         UPDATE_VTIME __LC_EXIT_TIMER,__LC_ASYNC_ENTER_TIMER,__LC_USER_TIMER
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER
 ext_no_vtime:
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         TRACE_IRQS_OFF
         la      %r2,SP_PTREGS(%r15)     # address of register-save area
         l       %r3,__LC_CPU_ADDRESS    # get cpu address + interruption code
@@ -777,7 +780,10 @@ mcck_int_main:
         sra     %r14,PAGE_SHIFT
         be      BASED(0f)
         l       %r15,__LC_PANIC_STACK   # load panic stack
-0:      CREATE_STACK_FRAME __LC_MCK_OLD_PSW,__LC_SAVE_AREA+32
+0:      s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
+        CREATE_STACK_FRAME __LC_SAVE_AREA+32
+        mvc     SP_PSW(8,%r15),0(%r12)
+        l       %r12,__LC_THREAD_INFO   # load pointer to thread_info struct
         tm      __LC_MCCK_CODE+2,0x08   # mwp of old psw valid?
         bno     BASED(mcck_no_vtime)    # no -> skip cleanup critical
         tm      SP_PSW+1(%r15),0x01     # interrupting from user ?
@@ -786,7 +792,6 @@ mcck_int_main:
         UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
         mvc     __LC_LAST_UPDATE_TIMER(8),__LC_MCCK_ENTER_TIMER
 mcck_no_vtime:
-        l       %r9,__LC_THREAD_INFO    # load pointer to thread_info struct
         la      %r2,SP_PTREGS(%r15)     # load pt_regs
         l       %r1,BASED(.Ls390_mcck)
         basr    %r14,%r1                # call machine check handler
@@ -798,7 +803,7 @@ mcck_no_vtime:
         xc      __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain
         lr      %r15,%r1
         stosm   __SF_EMPTY(%r15),0x04   # turn dat on
-        tm      __TI_flags+3(%r9),_TIF_MCCK_PENDING
+        tm      __TI_flags+3(%r12),_TIF_MCCK_PENDING
         bno     BASED(mcck_return)
         TRACE_IRQS_OFF
         l       %r1,BASED(.Ls390_handle_mcck)
@@ -947,12 +952,13 @@ cleanup_system_call:
         bh      BASED(0f)
         mvc     __LC_SAVE_AREA(16),0(%r12)
 0:      st      %r13,4(%r12)
-        st      %r12,__LC_SAVE_AREA+48  # argh
-        SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
-        CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
-        l       %r12,__LC_SAVE_AREA+48  # argh
+        l       %r15,__LC_KERNEL_STACK  # problem state -> load ksp
+        s       %r15,BASED(.Lc_spsize)  # make room for registers & psw
         st      %r15,12(%r12)
-        lh      %r7,0x8a
+        CREATE_STACK_FRAME __LC_SAVE_AREA
+        mvc     SP_PSW(8,%r15),__LC_SVC_OLD_PSW
+        mvc     SP_ILC(4,%r15),__LC_SVC_ILC
+        mvc     0(4,%r12),__LC_THREAD_INFO
 cleanup_vtime:
         clc     __LC_RETURN_PSW+4(4),BASED(cleanup_system_call_insn+12)
         bhe     BASED(cleanup_stime)