KVM: s390: fix stale machine check data for guarded storage

When delivering a machine check the CPU state is "loaded", which
means that some registers are already in the host registers.
Before writing the register content into the machine check
save area, we must make sure that we save the content of the
registers into the data structures that are used for delivering
the machine check.
We already do the right thing for access, vector/floating point
registers, let's do the same for guarded storage.

Fixes: 4e0b1ab72b8a ("KVM: s390: gs support for kvm guests")
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 482673e3436d652d63940d3d39c73f8cc08b885b..caf15c8a8948e76c1bf7cfb5d5a109df6cee9b3e 100644 (file)
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -419,6 +419,8 @@ static int __write_machine_check(struct kvm_vcpu *vcpu,
        /* take care of lazy register loading */
        save_fpu_regs();
        save_access_regs(vcpu->run->s.regs.acrs);
+       if (MACHINE_HAS_GS && vcpu->arch.gs_enabled)
+               save_gs_cb(current->thread.gs_cb);
 
        /* Extended save area */
        rc = read_guest_lc(vcpu, __LC_MCESAD, &ext_sa_addr,