linux_dsm_epyc7002/virt/kvm/arm/hyp/vgic-v3-sr.c
Marc Zyngier cffcd9df10 KVM: arm/arm64: vgic-v3: Fix off-by-one LR access
When iterating over the used LRs, be careful not to try to access
an unused LR, or even an unimplemented one if you're unlucky...

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-04-19 17:28:38 +02:00

290 lines
6.7 KiB
C

/*
* Copyright (C) 2012-2015 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/compiler.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <linux/kvm_host.h>
#include <asm/kvm_hyp.h>
#define vtr_to_max_lr_idx(v) ((v) & 0xf)
#define vtr_to_nr_pri_bits(v) (((u32)(v) >> 29) + 1)
static u64 __hyp_text __gic_v3_get_lr(unsigned int lr)
{
switch (lr & 0xf) {
case 0:
return read_gicreg(ICH_LR0_EL2);
case 1:
return read_gicreg(ICH_LR1_EL2);
case 2:
return read_gicreg(ICH_LR2_EL2);
case 3:
return read_gicreg(ICH_LR3_EL2);
case 4:
return read_gicreg(ICH_LR4_EL2);
case 5:
return read_gicreg(ICH_LR5_EL2);
case 6:
return read_gicreg(ICH_LR6_EL2);
case 7:
return read_gicreg(ICH_LR7_EL2);
case 8:
return read_gicreg(ICH_LR8_EL2);
case 9:
return read_gicreg(ICH_LR9_EL2);
case 10:
return read_gicreg(ICH_LR10_EL2);
case 11:
return read_gicreg(ICH_LR11_EL2);
case 12:
return read_gicreg(ICH_LR12_EL2);
case 13:
return read_gicreg(ICH_LR13_EL2);
case 14:
return read_gicreg(ICH_LR14_EL2);
case 15:
return read_gicreg(ICH_LR15_EL2);
}
unreachable();
}
static void __hyp_text __gic_v3_set_lr(u64 val, int lr)
{
switch (lr & 0xf) {
case 0:
write_gicreg(val, ICH_LR0_EL2);
break;
case 1:
write_gicreg(val, ICH_LR1_EL2);
break;
case 2:
write_gicreg(val, ICH_LR2_EL2);
break;
case 3:
write_gicreg(val, ICH_LR3_EL2);
break;
case 4:
write_gicreg(val, ICH_LR4_EL2);
break;
case 5:
write_gicreg(val, ICH_LR5_EL2);
break;
case 6:
write_gicreg(val, ICH_LR6_EL2);
break;
case 7:
write_gicreg(val, ICH_LR7_EL2);
break;
case 8:
write_gicreg(val, ICH_LR8_EL2);
break;
case 9:
write_gicreg(val, ICH_LR9_EL2);
break;
case 10:
write_gicreg(val, ICH_LR10_EL2);
break;
case 11:
write_gicreg(val, ICH_LR11_EL2);
break;
case 12:
write_gicreg(val, ICH_LR12_EL2);
break;
case 13:
write_gicreg(val, ICH_LR13_EL2);
break;
case 14:
write_gicreg(val, ICH_LR14_EL2);
break;
case 15:
write_gicreg(val, ICH_LR15_EL2);
break;
}
}
void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
{
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
u64 val;
/*
* Make sure stores to the GIC via the memory mapped interface
* are now visible to the system register interface.
*/
if (!cpu_if->vgic_sre) {
dsb(st);
cpu_if->vgic_vmcr = read_gicreg(ICH_VMCR_EL2);
}
if (used_lrs) {
int i;
u32 nr_pri_bits;
cpu_if->vgic_elrsr = read_gicreg(ICH_ELSR_EL2);
write_gicreg(0, ICH_HCR_EL2);
val = read_gicreg(ICH_VTR_EL2);
nr_pri_bits = vtr_to_nr_pri_bits(val);
for (i = 0; i < used_lrs; i++) {
if (cpu_if->vgic_elrsr & (1 << i))
cpu_if->vgic_lr[i] &= ~ICH_LR_STATE;
else
cpu_if->vgic_lr[i] = __gic_v3_get_lr(i);
__gic_v3_set_lr(0, i);
}
switch (nr_pri_bits) {
case 7:
cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
case 6:
cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
default:
cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
}
switch (nr_pri_bits) {
case 7:
cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
case 6:
cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
default:
cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
}
} else {
cpu_if->vgic_elrsr = 0xffff;
cpu_if->vgic_ap0r[0] = 0;
cpu_if->vgic_ap0r[1] = 0;
cpu_if->vgic_ap0r[2] = 0;
cpu_if->vgic_ap0r[3] = 0;
cpu_if->vgic_ap1r[0] = 0;
cpu_if->vgic_ap1r[1] = 0;
cpu_if->vgic_ap1r[2] = 0;
cpu_if->vgic_ap1r[3] = 0;
}
val = read_gicreg(ICC_SRE_EL2);
write_gicreg(val | ICC_SRE_EL2_ENABLE, ICC_SRE_EL2);
if (!cpu_if->vgic_sre) {
/* Make sure ENABLE is set at EL2 before setting SRE at EL1 */
isb();
write_gicreg(1, ICC_SRE_EL1);
}
}
void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
{
struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
u64 used_lrs = vcpu->arch.vgic_cpu.used_lrs;
u64 val;
u32 nr_pri_bits;
int i;
/*
* VFIQEn is RES1 if ICC_SRE_EL1.SRE is 1. This causes a
* Group0 interrupt (as generated in GICv2 mode) to be
* delivered as a FIQ to the guest, with potentially fatal
* consequences. So we must make sure that ICC_SRE_EL1 has
* been actually programmed with the value we want before
* starting to mess with the rest of the GIC, and VMCR_EL2 in
* particular.
*/
if (!cpu_if->vgic_sre) {
write_gicreg(0, ICC_SRE_EL1);
isb();
write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
}
val = read_gicreg(ICH_VTR_EL2);
nr_pri_bits = vtr_to_nr_pri_bits(val);
if (used_lrs) {
write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
switch (nr_pri_bits) {
case 7:
write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
case 6:
write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
default:
write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
}
switch (nr_pri_bits) {
case 7:
write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
case 6:
write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
default:
write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
}
for (i = 0; i < used_lrs; i++)
__gic_v3_set_lr(cpu_if->vgic_lr[i], i);
}
/*
* Ensures that the above will have reached the
* (re)distributors. This ensure the guest will read the
* correct values from the memory-mapped interface.
*/
if (!cpu_if->vgic_sre) {
isb();
dsb(sy);
}
/*
* Prevent the guest from touching the GIC system registers if
* SRE isn't enabled for GICv3 emulation.
*/
write_gicreg(read_gicreg(ICC_SRE_EL2) & ~ICC_SRE_EL2_ENABLE,
ICC_SRE_EL2);
}
void __hyp_text __vgic_v3_init_lrs(void)
{
int max_lr_idx = vtr_to_max_lr_idx(read_gicreg(ICH_VTR_EL2));
int i;
for (i = 0; i <= max_lr_idx; i++)
__gic_v3_set_lr(0, i);
}
u64 __hyp_text __vgic_v3_get_ich_vtr_el2(void)
{
return read_gicreg(ICH_VTR_EL2);
}
u64 __hyp_text __vgic_v3_read_vmcr(void)
{
return read_gicreg(ICH_VMCR_EL2);
}
void __hyp_text __vgic_v3_write_vmcr(u32 vmcr)
{
write_gicreg(vmcr, ICH_VMCR_EL2);
}