Commit ba88649d authored by Marc Zyngier's avatar Marc Zyngier Committed by chenxiang
Browse files

KVM: arm64: vgic-v3: Add userspace selection for GICv3.3 NMI 

virt inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I97WGU

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/commit/?h=arm64/nmi&id=ce431bbdd68bd0f445c88f59fb11e3a16a6e1526



----------------------------------------------------------------

In order to allow the GIC NMI support to be selected from userspace,
add userspace access to GICD_TYPER, which allows the NMI support bit
to be set.

This is gated by a global capability that nobody can set yet, so
no observable change is expected. Again.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Signed-off-by: default avatarXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: default avatarcaijian <caijian11@h-partners.com>
parent 620365f7

arch/arm64/kvm/vgic/vgic-init.c

+9 −1
Original line number Diff line number Diff line
@@ -353,8 +353,16 @@ int vgic_init(struct kvm *kvm) 
	 * If userspace didn't set the GIC implementation revision,

	 * default to the latest and greatest. You know want it.

	 */

	if (!dist->implementation_rev)

	if (!dist->implementation_rev) {

		dist->implementation_rev = KVM_VGIC_IMP_REV_LATEST;

		/*

		 * Advertise NMI if available. Userspace that explicitly

		 * doesn't want NMI will have written to GICD_{IIDR,TYPER}

		 * to set the implementation and the NMI support status.

		 */

		dist->has_nmi = kvm_vgic_global_state.has_nmi;

	}



	dist->initialized = true;



out:

arch/arm64/kvm/vgic/vgic-mmio-v2.c

+1 −0
Original line number Diff line number Diff line
@@ -95,6 +95,7 @@ static int vgic_mmio_uaccess_write_v2_misc(struct kvm_vcpu *vcpu, 
		switch (reg) {

		case KVM_VGIC_IMP_REV_2:

		case KVM_VGIC_IMP_REV_3:

		case KVM_VGIC_IMP_REV_4:

			vcpu->kvm->arch.vgic.v2_groups_user_writable = true;

			dist->implementation_rev = reg;

			return 0;

arch/arm64/kvm/vgic/vgic-mmio-v3.c

+14 −1
Original line number Diff line number Diff line
@@ -78,6 +78,8 @@ static unsigned long vgic_mmio_read_v3_misc(struct kvm_vcpu *vcpu, 
	case GICD_TYPER:

		value = vgic->nr_spis + VGIC_NR_PRIVATE_IRQS;

		value = (value >> 5) - 1;

		if (vgic->has_nmi)

			value |= GICD_TYPER_NMI;

		if (vgic_has_its(vcpu->kvm)) {

			value |= (INTERRUPT_ID_BITS_ITS - 1) << 19;

			value |= GICD_TYPER_LPIS;
@@ -158,6 +160,13 @@ static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu, 
	u32 reg;



	switch (addr & 0x0c) {

	case GICD_TYPER:

		if (dist->implementation_rev >= KVM_VGIC_IMP_REV_4 &&

		    kvm_vgic_global_state.has_nmi)

			dist->has_nmi = val & GICD_TYPER_NMI;

		else if (val & GICD_TYPER_NMI)

			return -EINVAL;

		return 0;

	case GICD_TYPER2:

		if (val != vgic_mmio_read_v3_misc(vcpu, addr, len))

			return -EINVAL;
@@ -171,6 +180,10 @@ static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu, 
		switch (reg) {

		case KVM_VGIC_IMP_REV_2:

		case KVM_VGIC_IMP_REV_3:

			/* Disable NMI on selecting an older revision */

			dist->has_nmi = false;

			fallthrough;

		case KVM_VGIC_IMP_REV_4:

			dist->implementation_rev = reg;

			return 0;

		default:
@@ -186,7 +199,7 @@ static int vgic_mmio_uaccess_write_v3_misc(struct kvm_vcpu *vcpu, 
		return 0;

	}



	vgic_mmio_write_v3_misc(vcpu, addr, len, val);

	/* Not reachable... */

	return 0;

}

include/kvm/arm_vgic.h

+5 −1
Original line number Diff line number Diff line
@@ -108,6 +108,9 @@ struct vgic_global { 
	bool			has_gicv4;

	bool			has_gicv4_1;



	/* NMI */

	bool			has_nmi;



	/* Pseudo GICv3 from outer space */

	bool			no_hw_deactivation;
@@ -288,7 +291,8 @@ struct vgic_dist { 
	u32			implementation_rev;

#define KVM_VGIC_IMP_REV_2	2 /* GICv2 restorable groups */

#define KVM_VGIC_IMP_REV_3	3 /* GICv3 GICR_CTLR.{IW,CES,RWP} */

#define KVM_VGIC_IMP_REV_LATEST	KVM_VGIC_IMP_REV_3

#define KVM_VGIC_IMP_REV_4	4 /* GICv3 NMI */

#define KVM_VGIC_IMP_REV_LATEST	KVM_VGIC_IMP_REV_4



	/* Userspace can write to GICv2 IGROUPR */

	bool			v2_groups_user_writable;