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| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2012-06-05 09:59:52 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2012-06-14 09:09:02 +0200 |
| commit | fbe765680d1fe9d08187ea4dad5041a7955a2c3a (patch) | |
| tree | cfa5ba11106bb5535552cf6b29ff6aa81f32c606 /arch/s390/kernel/entry64.S | |
| parent | 72f6e3a8bc956fddf6e004ae9b804977d1458e77 (diff) | |
| download | linux-fbe765680d1fe9d08187ea4dad5041a7955a2c3a.tar.bz2 | |
s390/smp: make absolute lowcore / cpu restart parameter accesses more robust
Setting the cpu restart parameters is done in three different fashions:
- directly setting the four parameters individually
- copying the four parameters with memcpy (using 4 * sizeof(long))
- copying the four parameters using a private structure
In addition code in entry*.S relies on a certain order of the restart
members of struct _lowcore.
Make all of this more robust to future changes by adding a
mem_absolute_assign(dest, val) define, which assigns val to dest
using absolute addressing mode. Also the load multiple instructions
in entry*.S have been split into separate load instruction so the
order of the struct _lowcore members doesn't matter anymore.
In addition move the prototypes of memcpy_real/absolute from uaccess.h
to processor.h. These memcpy* variants are not related to uaccess at all.
string.h doesn't seem to match as well, so lets use processor.h.
Also replace the eight byte array in struct _lowcore which represents a
misaliged u64 with a u64. The compiler will always create code that
handles the misaligned u64 correctly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/entry64.S')
| -rw-r--r-- | arch/s390/kernel/entry64.S | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index d5f02e480e51..2813e831ba32 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -751,7 +751,9 @@ ENTRY(restart_int_handler) mvc __PT_PSW(16,%r15),__LC_RST_OLD_PSW # store restart old psw aghi %r15,-STACK_FRAME_OVERHEAD # create stack frame on stack xc 0(STACK_FRAME_OVERHEAD,%r15),0(%r15) - lmg %r1,%r3,__LC_RESTART_FN # load fn, parm & source cpu + lg %r1,__LC_RESTART_FN # load fn, parm & source cpu + lg %r2,__LC_RESTART_DATA + lg %r3,__LC_RESTART_SOURCE ltgr %r3,%r3 # test source cpu address jm 1f # negative -> skip source stop 0: sigp %r4,%r3,SIGP_SENSE # sigp sense to source cpu |