[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, 40 insertions, 1 deletions

diff --git a/arch/s390/kernel/relocate_kernel.S b/arch/s390/kernel/relocate_kernel.S
index d5e4a62fbb79..2a25ec7147ff 100644
--- a/arch/s390/kernel/relocate_kernel.S
+++ b/arch/s390/kernel/relocate_kernel.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>
  *
  */
 
@@ -25,8 +26,31 @@
         relocate_kernel:
                 basr    %r13,0          #base address
         .base:
-                spx     zero64-.base(%r13)      #absolute addressing mode
                 stnsm   sys_msk-.base(%r13),0xf8        #disable DAT and IRQ (external)
+                spx     zero64-.base(%r13)      #absolute addressing mode
+                stctl   %c0,%c15,ctlregs-.base(%r13)
+                stm     %r0,%r15,gprregs-.base(%r13)
+                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
+                mvc     0x68(8,%r0),0(%r1)
+                la      %r0,.back_pgm-.base(%r13)
+                st      %r0,0x6c(%r0)
+                oi      0x6c(%r0),0x80
+                lhi     %r0,0
+                diag    %r0,%r0,0x308
+        .back:
+                basr    %r13,0
+        .back_base:
+                oi      have_diag308-.back_base(%r13),0x01
+                lctl    %c0,%c15,ctlregs-.back_base(%r13)
+                lm      %r0,%r15,gprregs-.back_base(%r13)
+                j       .start_reloc
+        .back_pgm:
+                lm      %r0,%r15,gprregs-.base(%r13)
+        .start_reloc:
                 lhi     %r10,-1         #preparing the mask
                 sll     %r10,12         #shift it such that it becomes 0xf000
         .top:
@@ -63,6 +87,10 @@
                 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:
                 sr      %r1,%r1         #clear %r1
                 sr      %r2,%r2         #clear %r2
                 sigp    %r1,%r2,0x12    #set cpuid to zero
@@ -75,6 +103,17 @@
                 .long   0x00080000,0x80000000
         sys_msk:
                 .quad   0
+        ctlregs:
+                .rept   16
+                .long   0
+                .endr
+        gprregs:
+                .rept   16
+                .long   0
+                .endr
+        have_diag308:
+                .byte   0
+                .align  8
         relocate_kernel_end:
         .globl  relocate_kernel_len
         relocate_kernel_len: