diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2013-05-17 14:41:35 +0200 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2013-05-21 11:55:23 +0300 |
| commit | 49b99e1e0dedbd6cc93b2d2776b60fb7151ff3d7 (patch) | |
| tree | 204052379d35e6459207571b3e2bb1d460e2cef2 /arch/s390/kernel | |
| parent | 95d38fd0bcf1996082f5f8762e6f1c849755e0c6 (diff) | |
s390/kvm: Provide a way to prevent reentering SIE
Lets provide functions to prevent KVM from reentering SIE and
to kick cpus out of SIE. We cannot use the common kvm_vcpu_kick code,
since we need to kick out guests in places that hold architecture
specific locks (e.g. pgste lock) which might be necessary on the
other cpus - so no waiting possible.
So lets provide a bit in a private field of the sie control block
that acts as a gate keeper, after we claimed we are in SIE.
Please note that we do not reuse prog0c, since we want to access
that bit without atomic ops.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/s390/kernel')
| -rw-r--r-- | arch/s390/kernel/asm-offsets.c | 1 | ||||
| -rw-r--r-- | arch/s390/kernel/entry64.S | 4 |
2 files changed, 4 insertions, 1 deletions
diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c index 6456bbe1fbb1..78db6338695d 100644 --- a/arch/s390/kernel/asm-offsets.c +++ b/arch/s390/kernel/asm-offsets.c @@ -163,6 +163,7 @@ int main(void) DEFINE(__THREAD_trap_tdb, offsetof(struct task_struct, thread.trap_tdb)); DEFINE(__GMAP_ASCE, offsetof(struct gmap, asce)); DEFINE(__SIE_PROG0C, offsetof(struct kvm_s390_sie_block, prog0c)); + DEFINE(__SIE_PROG20, offsetof(struct kvm_s390_sie_block, prog20)); #endif /* CONFIG_32BIT */ return 0; } diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index c2e81b4ea42c..c7daeefb9864 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -958,7 +958,9 @@ sie_loop: lctlg %c1,%c1,__GMAP_ASCE(%r14) # load primary asce sie_gmap: lg %r14,__SF_EMPTY(%r15) # get control block pointer - oi __SIE_PROG0C+3(%r14),1 # we are in SIE now + oi __SIE_PROG0C+3(%r14),1 # we are going into SIE now + tm __SIE_PROG20+3(%r14),1 # last exit... + jnz sie_done LPP __SF_EMPTY(%r15) # set guest id sie 0(%r14) sie_done: |