From: Nicholas Piggin <npiggin@gmail.com>
Date: Mon, 12 Apr 2021 01:48:38 +0000 (+1000)
Subject: KVM: PPC: Book3S HV: Prevent radix guests setting LPCR[TC]
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=72c15287210f7433f5fcb55452b05e4b6ccc6c15;p=linux.git

KVM: PPC: Book3S HV: Prevent radix guests setting LPCR[TC]

Prevent radix guests setting LPCR[TC]. This bit only applies to hash
partitions.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210412014845.1517916-6-npiggin@gmail.com
---

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 3de8a1f89a7db..70c6e9c27eb75 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1645,6 +1645,10 @@ static int kvm_arch_vcpu_ioctl_set_sregs_hv(struct kvm_vcpu *vcpu,
  */
 unsigned long kvmppc_filter_lpcr_hv(struct kvm *kvm, unsigned long lpcr)
 {
+	/* LPCR_TC only applies to HPT guests */
+	if (kvm_is_radix(kvm))
+		lpcr &= ~LPCR_TC;
+
 	/* On POWER8 and above, userspace can modify AIL */
 	if (!cpu_has_feature(CPU_FTR_ARCH_207S))
 		lpcr &= ~LPCR_AIL;