KVM: PPC: PR: Handle FSCR feature deselects

We handle FSCR feature bits (well, TAR only really today) lazily when the guest
starts using them. So when a guest activates the bit and later uses that feature
we enable it for real in hardware.

However, when the guest stops using that bit we don't stop setting it in
hardware. That means we can potentially lose a trap that the guest expects to
happen because it thinks a feature is not active.

This patch adds support to drop TAR when then guest turns it off in FSCR. While
at it it also restricts FSCR access to 64bit systems - 32bit ones don't have it.

Signed-off-by: Alexander Graf <agraf@suse.de>
This commit is contained in:
Alexander Graf
2014-07-31 10:21:59 +02:00
parent 29577fc00b
commit 8e6afa36e7
3 changed files with 14 additions and 4 deletions

View File

@@ -449,10 +449,10 @@ int kvmppc_core_emulate_mtspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val)
case SPRN_GQR7:
to_book3s(vcpu)->gqr[sprn - SPRN_GQR0] = spr_val;
break;
case SPRN_FSCR:
vcpu->arch.fscr = spr_val;
break;
#ifdef CONFIG_PPC_BOOK3S_64
case SPRN_FSCR:
kvmppc_set_fscr(vcpu, spr_val);
break;
case SPRN_BESCR:
vcpu->arch.bescr = spr_val;
break;
@@ -593,10 +593,10 @@ int kvmppc_core_emulate_mfspr_pr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val
case SPRN_GQR7:
*spr_val = to_book3s(vcpu)->gqr[sprn - SPRN_GQR0];
break;
#ifdef CONFIG_PPC_BOOK3S_64
case SPRN_FSCR:
*spr_val = vcpu->arch.fscr;
break;
#ifdef CONFIG_PPC_BOOK3S_64
case SPRN_BESCR:
*spr_val = vcpu->arch.bescr;
break;