linux_dsm_epyc7002/arch/s390/kvm
David Hildenbrand b3ecd4aa86 KVM: s390: vsie: use READ_ONCE to access some SCB fields
Another VCPU might try to modify the SCB while we are creating the
shadow SCB. In general this is no problem - unless the compiler decides
to not load values once, but e.g. twice.

For us, this is only relevant when checking/working with such values.
E.g. the prefix value, the mso, state of transactional execution and
addresses of satellite blocks.

E.g. if we blindly forward values (e.g. general purpose registers or
execution controls after masking), we don't care.

Leaving unpin_blocks() untouched for now, will handle it separately.

The worst thing right now that I can see would be a missed prefix
un/remap (mso, prefix, tx) or using wrong guest addresses. Nothing
critical, but let's try to avoid unpredictable behavior.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20180116171526.12343-2-david@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-01-24 14:05:00 +01:00
..
diag.c KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
gaccess.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gaccess.h KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
guestdbg.c KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
intercept.c KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
interrupt.c KVM: s390: cleanup struct kvm_s390_float_interrupt 2018-01-16 16:15:18 +01:00
irq.h KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
Kconfig License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kvm-s390.c KVM: s390: cleanup struct kvm_s390_float_interrupt 2018-01-16 16:15:18 +01:00
kvm-s390.h KVM: s390: cleanup struct kvm_s390_float_interrupt 2018-01-16 16:15:18 +01:00
Makefile KVM: s390: Remove redundant license text 2017-12-06 09:18:42 +01:00
priv.c KVM: s390: Fix skey emulation permission check 2017-12-06 09:18:43 +01:00
sigp.c KVM: s390: cleanup struct kvm_s390_float_interrupt 2018-01-16 16:15:18 +01:00
trace-s390.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vsie.c KVM: s390: vsie: use READ_ONCE to access some SCB fields 2018-01-24 14:05:00 +01:00