KVM: PPC: Book3S HV: Don't do ultravisor calls on systems without ultravisor

Commit 22945688ac ("KVM: PPC: Book3S HV: Support reset of secure
guest") added a call to uv_svm_terminate, which is an ultravisor
call, without any check that the guest is a secure guest or even that
the system has an ultravisor.  On a system without an ultravisor,
the ultracall will degenerate to a hypercall, but since we are not
in KVM guest context, the hypercall will get treated as a system
call, which could have random effects depending on what happens to
be in r0, and could also corrupt the current task's kernel stack.
Hence this adds a test for the guest being a secure guest before
doing uv_svm_terminate().

Fixes: 22945688ac ("KVM: PPC: Book3S HV: Support reset of secure guest")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Paul Mackerras 2019-12-18 11:43:06 +11:00
parent 7d73710d9c
commit d89c69f42b
1 changed files with 2 additions and 1 deletions

View File

@ -4983,7 +4983,8 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
if (nesting_enabled(kvm))
kvmhv_release_all_nested(kvm);
kvm->arch.process_table = 0;
uv_svm_terminate(kvm->arch.lpid);
if (kvm->arch.secure_guest)
uv_svm_terminate(kvm->arch.lpid);
kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0);
}