Merge tag 'kvmarm-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for Linux 5.8, take #1

* 32bit VM fixes:
  - Fix embarassing mapping issue between AArch32 CSSELR and AArch64
    ACTLR
  - Add ACTLR2 support for AArch32
  - Get rid of the useless ACTLR_EL1 save/restore
  - Fix CP14/15 accesses for AArch32 guests on BE hosts
  - Ensure that we don't loose any state when injecting a 32bit
    exception when running on a VHE host

* 64bit VM fixes:
  - Fix PtrAuth host saving happening in preemptible contexts
  - Optimize PtrAuth lazy enable
  - Drop vcpu to cpu context pointer
  - Fix sparse warnings for HYP per-CPU accesses

1 files changed, 28 insertions, 0 deletions

diff --git a/arch/arm64/kvm/aarch32.c b/arch/arm64/kvm/aarch32.c
index 0a356aa91aa1..40a62a99fbf8 100644
--- a/arch/arm64/kvm/aarch32.c
+++ b/arch/arm64/kvm/aarch32.c
@@ -33,6 +33,26 @@ static const u8 return_offsets[8][2] = {
 	[7] = { 4, 4 },		/* FIQ, unused */
 };
 
+static bool pre_fault_synchronize(struct kvm_vcpu *vcpu)
+{
+	preempt_disable();
+	if (vcpu->arch.sysregs_loaded_on_cpu) {
+		kvm_arch_vcpu_put(vcpu);
+		return true;
+	}
+
+	preempt_enable();
+	return false;
+}
+
+static void post_fault_synchronize(struct kvm_vcpu *vcpu, bool loaded)
+{
+	if (loaded) {
+		kvm_arch_vcpu_load(vcpu, smp_processor_id());
+		preempt_enable();
+	}
+}
+
 /*
  * When an exception is taken, most CPSR fields are left unchanged in the
  * handler. However, some are explicitly overridden (e.g. M[4:0]).
@@ -155,7 +175,10 @@ static void prepare_fault32(struct kvm_vcpu *vcpu, u32 mode, u32 vect_offset)
 
 void kvm_inject_undef32(struct kvm_vcpu *vcpu)
 {
+	bool loaded = pre_fault_synchronize(vcpu);
+
 	prepare_fault32(vcpu, PSR_AA32_MODE_UND, 4);
+	post_fault_synchronize(vcpu, loaded);
 }
 
 /*
@@ -168,6 +191,9 @@ static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt,
 	u32 vect_offset;
 	u32 *far, *fsr;
 	bool is_lpae;
+	bool loaded;
+
+	loaded = pre_fault_synchronize(vcpu);
 
 	if (is_pabt) {
 		vect_offset = 12;
@@ -191,6 +217,8 @@ static void inject_abt32(struct kvm_vcpu *vcpu, bool is_pabt,
 		/* no need to shuffle FS[4] into DFSR[10] as its 0 */
 		*fsr = DFSR_FSC_EXTABT_nLPAE;
 	}
+
+	post_fault_synchronize(vcpu, loaded);
 }
 
 void kvm_inject_dabt32(struct kvm_vcpu *vcpu, unsigned long addr)