[PATCH] s390: kexec fixes and improvements.

Disable pseudo page fault handling before starting the new kernel and try
to use diag308 to reset the machine.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 43 insertions, 2 deletions

diff --git a/arch/s390/kernel/relocate_kernel64.S b/arch/s390/kernel/relocate_kernel64.S
index 96290cc4eb3..8cdb86e8911 100644
--- a/arch/s390/kernel/relocate_kernel64.S
+++ b/arch/s390/kernel/relocate_kernel64.S
@@ -4,6 +4,7 @@
  * (C) Copyright IBM Corp. 2005
  *
  * Author(s): Rolf Adelsberger <adelsberger@de.ibm.com>
+ *            Heiko Carstens <heiko.carstens@de.ibm.com>
  *
  */
 
@@ -26,8 +27,34 @@
         relocate_kernel:
                 basr    %r13,0          #base address
         .base:
+                stnsm   sys_msk-.base(%r13),0xf8        #disable DAT and IRQs
                 spx     zero64-.base(%r13)      #absolute addressing mode
-                stnsm   sys_msk-.base(%r13),0xf8        #disable DAT and IRQ (external)
+                stctg   %c0,%c15,ctlregs-.base(%r13)
+                stmg    %r0,%r15,gprregs-.base(%r13)
+                lghi    %r0,3
+                sllg    %r0,%r0,31
+                stg     %r0,0x1d0(%r0)
+                la      %r0,.back_pgm-.base(%r13)
+                stg     %r0,0x1d8(%r0)
+                la      %r1,load_psw-.base(%r13)
+                mvc     0(8,%r0),0(%r1)
+                la      %r0,.back-.base(%r13)
+                st      %r0,4(%r0)
+                oi      4(%r0),0x80
+                lghi    %r0,0
+                diag    %r0,%r0,0x308
+        .back:
+                lhi     %r1,1           #mode 1 = esame
+                sigp    %r1,%r0,0x12    #switch to esame mode
+                sam64                   #switch to 64 bit addressing mode
+                basr    %r13,0
+        .back_base:
+                oi      have_diag308-.back_base(%r13),0x01
+                lctlg   %c0,%c15,ctlregs-.back_base(%r13)
+                lmg     %r0,%r15,gprregs-.back_base(%r13)
+                j       .top
+        .back_pgm:
+                lmg     %r0,%r15,gprregs-.base(%r13)
         .top:
                 lghi    %r7,4096        #load PAGE_SIZE in r7
                 lghi    %r9,4096        #load PAGE_SIZE in r9
@@ -62,6 +89,10 @@
                 o       %r3,4(%r4)      #or load address into psw
                 st      %r3,4(%r4)
                 mvc     0(8,%r0),0(%r4) #copy psw to absolute address 0
+                tm      have_diag308-.base(%r13),0x01
+                jno     .no_diag308
+                diag    %r0,%r0,0x308
+        .no_diag308:
                 sam31                   #31 bit mode
                 sr      %r1,%r1         #erase register r1
                 sr      %r2,%r2         #erase register r2
@@ -75,8 +106,18 @@
                 .long   0x00080000,0x80000000
         sys_msk:
                 .quad   0
+        ctlregs:
+                .rept   16
+                .quad   0
+                .endr
+        gprregs:
+                .rept   16
+                .quad   0
+                .endr
+        have_diag308:
+                .byte   0
+                .align  8
         relocate_kernel_end:
         .globl  relocate_kernel_len
         relocate_kernel_len:
                 .quad   relocate_kernel_end - relocate_kernel
-