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| author | Marc Zyngier <marc.zyngier@arm.com> | 2017-05-02 14:30:41 +0100 |
|---|---|---|
| committer | Christoffer Dall <cdall@linaro.org> | 2017-05-15 11:32:04 +0200 |
| commit | 15d2bffdde6268883647c6112970f74d3e1af651 (patch) | |
| tree | c30636f3152d7d074fe41097fc349aa4432504b1 /virt | |
| parent | 3d6e77ad1489650afa20da92bb589c8778baa8da (diff) | |
| download | linux-15d2bffdde6268883647c6112970f74d3e1af651.tar.gz linux-15d2bffdde6268883647c6112970f74d3e1af651.tar.bz2 linux-15d2bffdde6268883647c6112970f74d3e1af651.zip | |
KVM: arm/arm64: vgic-v3: Use PREbits to infer the number of ICH_APxRn_EL2 registers
The GICv3 documentation is extremely confusing, as it talks about
the number of priorities represented by the ICH_APxRn_EL2 registers,
while it should really talk about the number of preemption levels.
This leads to a bug where we may access undefined ICH_APxRn_EL2
registers, since PREbits is allowed to be smaller than PRIbits.
Thankfully, nobody seem to have taken this path so far...
The fix is to use ICH_VTR_EL2.PREbits instead.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/hyp/vgic-v3-sr.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c index bce6037cf01d..32c3295929b0 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -22,7 +22,7 @@ #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) +#define vtr_to_nr_pre_bits(v) (((u32)(v) >> 26) + 1) static u64 __hyp_text __gic_v3_get_lr(unsigned int lr) { @@ -135,13 +135,13 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu) if (used_lrs) { int i; - u32 nr_pri_bits; + u32 nr_pre_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); + nr_pre_bits = vtr_to_nr_pre_bits(val); for (i = 0; i < used_lrs; i++) { if (cpu_if->vgic_elrsr & (1 << i)) @@ -152,7 +152,7 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu) __gic_v3_set_lr(0, i); } - switch (nr_pri_bits) { + switch (nr_pre_bits) { case 7: cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2); cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2); @@ -162,7 +162,7 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu) cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2); } - switch (nr_pri_bits) { + switch (nr_pre_bits) { case 7: cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2); cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2); @@ -198,7 +198,7 @@ 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; + u32 nr_pre_bits; int i; /* @@ -217,12 +217,12 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu) } val = read_gicreg(ICH_VTR_EL2); - nr_pri_bits = vtr_to_nr_pri_bits(val); + nr_pre_bits = vtr_to_nr_pre_bits(val); if (used_lrs) { write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2); - switch (nr_pri_bits) { + switch (nr_pre_bits) { case 7: write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2); write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2); @@ -232,7 +232,7 @@ void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu) write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2); } - switch (nr_pri_bits) { + switch (nr_pre_bits) { case 7: write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2); write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2); |