From 3435bd79ec13369281f87155b9b612ad0a379795 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 18 Jul 2025 12:11:54 +0100 Subject: [PATCH] KVM: arm64: selftest: vgic-v3: Add basic GICv3 sysreg userspace access test We have a lot of more or less useful vgic tests, but none of them tracks the availability of GICv3 system registers, which is a bit annoying. Add one such test, which covers both EL1 and EL2 registers. Signed-off-by: Marc Zyngier Tested-by: Itaru Kitayama Reviewed-by: Sebastian Ott Link: https://lore.kernel.org/r/20250718111154.104029-5-maz@kernel.org Signed-off-by: Oliver Upton --- tools/testing/selftests/kvm/arm64/vgic_init.c | 219 +++++++++++++++++- 1 file changed, 217 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kvm/arm64/vgic_init.c b/tools/testing/selftests/kvm/arm64/vgic_init.c index b3b5fb0ff0a9a..7d508dcdbf23d 100644 --- a/tools/testing/selftests/kvm/arm64/vgic_init.c +++ b/tools/testing/selftests/kvm/arm64/vgic_init.c @@ -9,6 +9,8 @@ #include #include +#include + #include "test_util.h" #include "kvm_util.h" #include "processor.h" @@ -18,8 +20,6 @@ #define REG_OFFSET(vcpu, offset) (((uint64_t)vcpu << 32) | offset) -#define GICR_TYPER 0x8 - #define VGIC_DEV_IS_V2(_d) ((_d) == KVM_DEV_TYPE_ARM_VGIC_V2) #define VGIC_DEV_IS_V3(_d) ((_d) == KVM_DEV_TYPE_ARM_VGIC_V3) @@ -715,6 +715,220 @@ int test_kvm_device(uint32_t gic_dev_type) return 0; } +struct sr_def { + const char *name; + u32 encoding; +}; + +#define PACK_SR(r) \ + ((sys_reg_Op0(r) << 14) | \ + (sys_reg_Op1(r) << 11) | \ + (sys_reg_CRn(r) << 7) | \ + (sys_reg_CRm(r) << 3) | \ + (sys_reg_Op2(r))) + +#define SR(r) \ + { \ + .name = #r, \ + .encoding = r, \ + } + +static const struct sr_def sysregs_el1[] = { + SR(SYS_ICC_PMR_EL1), + SR(SYS_ICC_BPR0_EL1), + SR(SYS_ICC_AP0R0_EL1), + SR(SYS_ICC_AP0R1_EL1), + SR(SYS_ICC_AP0R2_EL1), + SR(SYS_ICC_AP0R3_EL1), + SR(SYS_ICC_AP1R0_EL1), + SR(SYS_ICC_AP1R1_EL1), + SR(SYS_ICC_AP1R2_EL1), + SR(SYS_ICC_AP1R3_EL1), + SR(SYS_ICC_BPR1_EL1), + SR(SYS_ICC_CTLR_EL1), + SR(SYS_ICC_SRE_EL1), + SR(SYS_ICC_IGRPEN0_EL1), + SR(SYS_ICC_IGRPEN1_EL1), +}; + +static const struct sr_def sysregs_el2[] = { + SR(SYS_ICH_AP0R0_EL2), + SR(SYS_ICH_AP0R1_EL2), + SR(SYS_ICH_AP0R2_EL2), + SR(SYS_ICH_AP0R3_EL2), + SR(SYS_ICH_AP1R0_EL2), + SR(SYS_ICH_AP1R1_EL2), + SR(SYS_ICH_AP1R2_EL2), + SR(SYS_ICH_AP1R3_EL2), + SR(SYS_ICH_HCR_EL2), + SR(SYS_ICC_SRE_EL2), + SR(SYS_ICH_VTR_EL2), + SR(SYS_ICH_VMCR_EL2), + SR(SYS_ICH_LR0_EL2), + SR(SYS_ICH_LR1_EL2), + SR(SYS_ICH_LR2_EL2), + SR(SYS_ICH_LR3_EL2), + SR(SYS_ICH_LR4_EL2), + SR(SYS_ICH_LR5_EL2), + SR(SYS_ICH_LR6_EL2), + SR(SYS_ICH_LR7_EL2), + SR(SYS_ICH_LR8_EL2), + SR(SYS_ICH_LR9_EL2), + SR(SYS_ICH_LR10_EL2), + SR(SYS_ICH_LR11_EL2), + SR(SYS_ICH_LR12_EL2), + SR(SYS_ICH_LR13_EL2), + SR(SYS_ICH_LR14_EL2), + SR(SYS_ICH_LR15_EL2), +}; + +static void test_sysreg_array(int gic, const struct sr_def *sr, int nr, + int (*check)(int, const struct sr_def *, const char *)) +{ + for (int i = 0; i < nr; i++) { + u64 val; + u64 attr; + int ret; + + /* Assume MPIDR_EL1.Aff*=0 */ + attr = PACK_SR(sr[i].encoding); + + /* + * The API is braindead. A register can be advertised as + * available, and yet not be readable or writable. + * ICC_APnR{1,2,3}_EL1 are examples of such non-sense, and + * ICH_APnR{1,2,3}_EL2 do follow suit for consistency. + * + * On the bright side, no known HW is implementing more than + * 5 bits of priority, so we're safe. Sort of... + */ + ret = __kvm_has_device_attr(gic, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS, + attr); + TEST_ASSERT(ret == 0, "%s unavailable", sr[i].name); + + /* Check that we can write back what we read */ + ret = __kvm_device_attr_get(gic, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS, + attr, &val); + TEST_ASSERT(ret == 0 || !check(gic, &sr[i], "read"), "%s unreadable", sr[i].name); + ret = __kvm_device_attr_set(gic, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS, + attr, &val); + TEST_ASSERT(ret == 0 || !check(gic, &sr[i], "write"), "%s unwritable", sr[i].name); + } +} + +static u8 get_ctlr_pribits(int gic) +{ + int ret; + u64 val; + u8 pri; + + ret = __kvm_device_attr_get(gic, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS, + PACK_SR(SYS_ICC_CTLR_EL1), &val); + TEST_ASSERT(ret == 0, "ICC_CTLR_EL1 unreadable"); + + pri = FIELD_GET(ICC_CTLR_EL1_PRI_BITS_MASK, val) + 1; + TEST_ASSERT(pri >= 5 && pri <= 7, "Bad pribits %d", pri); + + return pri; +} + +static int check_unaccessible_el1_regs(int gic, const struct sr_def *sr, const char *what) +{ + switch (sr->encoding) { + case SYS_ICC_AP0R1_EL1: + case SYS_ICC_AP1R1_EL1: + if (get_ctlr_pribits(gic) >= 6) + return -EINVAL; + break; + case SYS_ICC_AP0R2_EL1: + case SYS_ICC_AP0R3_EL1: + case SYS_ICC_AP1R2_EL1: + case SYS_ICC_AP1R3_EL1: + if (get_ctlr_pribits(gic) == 7) + return 0; + break; + default: + return -EINVAL; + } + + pr_info("SKIP %s for %s\n", sr->name, what); + return 0; +} + +static u8 get_vtr_pribits(int gic) +{ + int ret; + u64 val; + u8 pri; + + ret = __kvm_device_attr_get(gic, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS, + PACK_SR(SYS_ICH_VTR_EL2), &val); + TEST_ASSERT(ret == 0, "ICH_VTR_EL2 unreadable"); + + pri = FIELD_GET(ICH_VTR_EL2_PRIbits, val) + 1; + TEST_ASSERT(pri >= 5 && pri <= 7, "Bad pribits %d", pri); + + return pri; +} + +static int check_unaccessible_el2_regs(int gic, const struct sr_def *sr, const char *what) +{ + switch (sr->encoding) { + case SYS_ICH_AP0R1_EL2: + case SYS_ICH_AP1R1_EL2: + if (get_vtr_pribits(gic) >= 6) + return -EINVAL; + break; + case SYS_ICH_AP0R2_EL2: + case SYS_ICH_AP0R3_EL2: + case SYS_ICH_AP1R2_EL2: + case SYS_ICH_AP1R3_EL2: + if (get_vtr_pribits(gic) == 7) + return -EINVAL; + break; + default: + return -EINVAL; + } + + pr_info("SKIP %s for %s\n", sr->name, what); + return 0; +} + +static void test_v3_sysregs(void) +{ + struct kvm_vcpu_init init = {}; + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + u32 feat = 0; + int gic; + + if (kvm_check_cap(KVM_CAP_ARM_EL2)) + feat |= BIT(KVM_ARM_VCPU_HAS_EL2); + + vm = vm_create(1); + + vm_ioctl(vm, KVM_ARM_PREFERRED_TARGET, &init); + init.features[0] |= feat; + + vcpu = aarch64_vcpu_add(vm, 0, &init, NULL); + TEST_ASSERT(vcpu, "Can't create a vcpu?"); + + gic = kvm_create_device(vm, KVM_DEV_TYPE_ARM_VGIC_V3); + TEST_ASSERT(gic >= 0, "No GIC???"); + + kvm_device_attr_set(gic, KVM_DEV_ARM_VGIC_GRP_CTRL, + KVM_DEV_ARM_VGIC_CTRL_INIT, NULL); + + test_sysreg_array(gic, sysregs_el1, ARRAY_SIZE(sysregs_el1), check_unaccessible_el1_regs); + if (feat) + test_sysreg_array(gic, sysregs_el2, ARRAY_SIZE(sysregs_el2), check_unaccessible_el2_regs); + else + pr_info("SKIP EL2 registers, not available\n"); + + close(gic); + kvm_vm_free(vm); +} + void run_tests(uint32_t gic_dev_type) { test_vcpus_then_vgic(gic_dev_type); @@ -730,6 +944,7 @@ void run_tests(uint32_t gic_dev_type) test_v3_last_bit_single_rdist(); test_v3_redist_ipa_range_check_at_vcpu_run(); test_v3_its_region(); + test_v3_sysregs(); } } -- 2.47.2