diff options
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 154 | ||||
| -rw-r--r-- | arch/arm64/kvm/sys_regs.h | 24 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/.gitignore | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/Makefile | 1 | ||||
| -rw-r--r-- | tools/testing/selftests/kvm/aarch64/aarch32_id_regs.c | 169 |
5 files changed, 261 insertions, 88 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 2ef1121ab844..f4a7c5abcbca 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1063,13 +1063,12 @@ static bool access_arch_timer(struct kvm_vcpu *vcpu, } /* Read a sanitised cpufeature ID register by sys_reg_desc */ -static u64 read_id_reg(const struct kvm_vcpu *vcpu, - struct sys_reg_desc const *r, bool raz) +static u64 read_id_reg(const struct kvm_vcpu *vcpu, struct sys_reg_desc const *r) { u32 id = reg_to_encoding(r); u64 val; - if (raz) + if (sysreg_visible_as_raz(vcpu, r)) return 0; val = read_sanitised_ftr_reg(id); @@ -1145,34 +1144,37 @@ static unsigned int id_visibility(const struct kvm_vcpu *vcpu, return 0; } -/* cpufeature ID register access trap handlers */ - -static bool __access_id_reg(struct kvm_vcpu *vcpu, - struct sys_reg_params *p, - const struct sys_reg_desc *r, - bool raz) +static unsigned int aa32_id_visibility(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) { - if (p->is_write) - return write_to_read_only(vcpu, p, r); + /* + * AArch32 ID registers are UNKNOWN if AArch32 isn't implemented at any + * EL. Promote to RAZ/WI in order to guarantee consistency between + * systems. + */ + if (!kvm_supports_32bit_el0()) + return REG_RAZ | REG_USER_WI; - p->regval = read_id_reg(vcpu, r, raz); - return true; + return id_visibility(vcpu, r); } +static unsigned int raz_visibility(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) +{ + return REG_RAZ; +} + +/* cpufeature ID register access trap handlers */ + static bool access_id_reg(struct kvm_vcpu *vcpu, struct sys_reg_params *p, const struct sys_reg_desc *r) { - bool raz = sysreg_visible_as_raz(vcpu, r); - - return __access_id_reg(vcpu, p, r, raz); -} + if (p->is_write) + return write_to_read_only(vcpu, p, r); -static bool access_raz_id_reg(struct kvm_vcpu *vcpu, - struct sys_reg_params *p, - const struct sys_reg_desc *r) -{ - return __access_id_reg(vcpu, p, r, true); + p->regval = read_id_reg(vcpu, r); + return true; } /* Visibility overrides for SVE-specific control registers */ @@ -1208,9 +1210,9 @@ static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu, return -EINVAL; /* We can only differ with CSV[23], and anything else is an error */ - val ^= read_id_reg(vcpu, rd, false); - val &= ~((0xFUL << ID_AA64PFR0_EL1_CSV2_SHIFT) | - (0xFUL << ID_AA64PFR0_EL1_CSV3_SHIFT)); + val ^= read_id_reg(vcpu, rd); + val &= ~(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV2) | + ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_CSV3)); if (val) return -EINVAL; @@ -1227,45 +1229,21 @@ static int set_id_aa64pfr0_el1(struct kvm_vcpu *vcpu, * are stored, and for set_id_reg() we don't allow the effective value * to be changed. */ -static int __get_id_reg(const struct kvm_vcpu *vcpu, - const struct sys_reg_desc *rd, u64 *val, - bool raz) -{ - *val = read_id_reg(vcpu, rd, raz); - return 0; -} - -static int __set_id_reg(const struct kvm_vcpu *vcpu, - const struct sys_reg_desc *rd, u64 val, - bool raz) -{ - /* This is what we mean by invariant: you can't change it. */ - if (val != read_id_reg(vcpu, rd, raz)) - return -EINVAL; - - return 0; -} - static int get_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, u64 *val) { - bool raz = sysreg_visible_as_raz(vcpu, rd); - - return __get_id_reg(vcpu, rd, val, raz); + *val = read_id_reg(vcpu, rd); + return 0; } static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, u64 val) { - bool raz = sysreg_visible_as_raz(vcpu, rd); - - return __set_id_reg(vcpu, rd, val, raz); -} + /* This is what we mean by invariant: you can't change it. */ + if (val != read_id_reg(vcpu, rd)) + return -EINVAL; -static int set_raz_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, - u64 val) -{ - return __set_id_reg(vcpu, rd, val, true); + return 0; } static int get_raz_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, @@ -1367,6 +1345,15 @@ static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, .visibility = id_visibility, \ } +/* sys_reg_desc initialiser for known cpufeature ID registers */ +#define AA32_ID_SANITISED(name) { \ + SYS_DESC(SYS_##name), \ + .access = access_id_reg, \ + .get_user = get_id_reg, \ + .set_user = set_id_reg, \ + .visibility = aa32_id_visibility, \ +} + /* * sys_reg_desc initialiser for architecturally unallocated cpufeature ID * register with encoding Op0=3, Op1=0, CRn=0, CRm=crm, Op2=op2 @@ -1374,9 +1361,10 @@ static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, */ #define ID_UNALLOCATED(crm, op2) { \ Op0(3), Op1(0), CRn(0), CRm(crm), Op2(op2), \ - .access = access_raz_id_reg, \ - .get_user = get_raz_reg, \ - .set_user = set_raz_id_reg, \ + .access = access_id_reg, \ + .get_user = get_id_reg, \ + .set_user = set_id_reg, \ + .visibility = raz_visibility \ } /* @@ -1386,9 +1374,10 @@ static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, */ #define ID_HIDDEN(name) { \ SYS_DESC(SYS_##name), \ - .access = access_raz_id_reg, \ - .get_user = get_raz_reg, \ - .set_user = set_raz_id_reg, \ + .access = access_id_reg, \ + .get_user = get_id_reg, \ + .set_user = set_id_reg, \ + .visibility = raz_visibility, \ } /* @@ -1452,33 +1441,33 @@ static const struct sys_reg_desc sys_reg_descs[] = { /* AArch64 mappings of the AArch32 ID registers */ /* CRm=1 */ - ID_SANITISED(ID_PFR0_EL1), - ID_SANITISED(ID_PFR1_EL1), - ID_SANITISED(ID_DFR0_EL1), + AA32_ID_SANITISED(ID_PFR0_EL1), + AA32_ID_SANITISED(ID_PFR1_EL1), + AA32_ID_SANITISED(ID_DFR0_EL1), ID_HIDDEN(ID_AFR0_EL1), - ID_SANITISED(ID_MMFR0_EL1), - ID_SANITISED(ID_MMFR1_EL1), - ID_SANITISED(ID_MMFR2_EL1), - ID_SANITISED(ID_MMFR3_EL1), + AA32_ID_SANITISED(ID_MMFR0_EL1), + AA32_ID_SANITISED(ID_MMFR1_EL1), + AA32_ID_SANITISED(ID_MMFR2_EL1), + AA32_ID_SANITISED(ID_MMFR3_EL1), /* CRm=2 */ - ID_SANITISED(ID_ISAR0_EL1), - ID_SANITISED(ID_ISAR1_EL1), - ID_SANITISED(ID_ISAR2_EL1), - ID_SANITISED(ID_ISAR3_EL1), - ID_SANITISED(ID_ISAR4_EL1), - ID_SANITISED(ID_ISAR5_EL1), - ID_SANITISED(ID_MMFR4_EL1), - ID_SANITISED(ID_ISAR6_EL1), + AA32_ID_SANITISED(ID_ISAR0_EL1), + AA32_ID_SANITISED(ID_ISAR1_EL1), + AA32_ID_SANITISED(ID_ISAR2_EL1), + AA32_ID_SANITISED(ID_ISAR3_EL1), + AA32_ID_SANITISED(ID_ISAR4_EL1), + AA32_ID_SANITISED(ID_ISAR5_EL1), + AA32_ID_SANITISED(ID_MMFR4_EL1), + AA32_ID_SANITISED(ID_ISAR6_EL1), /* CRm=3 */ - ID_SANITISED(MVFR0_EL1), - ID_SANITISED(MVFR1_EL1), - ID_SANITISED(MVFR2_EL1), + AA32_ID_SANITISED(MVFR0_EL1), + AA32_ID_SANITISED(MVFR1_EL1), + AA32_ID_SANITISED(MVFR2_EL1), ID_UNALLOCATED(3,3), - ID_SANITISED(ID_PFR2_EL1), + AA32_ID_SANITISED(ID_PFR2_EL1), ID_HIDDEN(ID_DFR1_EL1), - ID_SANITISED(ID_MMFR5_EL1), + AA32_ID_SANITISED(ID_MMFR5_EL1), ID_UNALLOCATED(3,7), /* AArch64 ID registers */ @@ -2809,6 +2798,9 @@ int kvm_sys_reg_set_user(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg, if (!r) return -ENOENT; + if (sysreg_user_write_ignore(vcpu, r)) + return 0; + if (r->set_user) { ret = (r->set_user)(vcpu, r, val); } else { diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index a8c4cc32eb9a..e4ebb3a379fd 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -86,6 +86,7 @@ struct sys_reg_desc { #define REG_HIDDEN (1 << 0) /* hidden from userspace and guest */ #define REG_RAZ (1 << 1) /* RAZ from userspace and guest */ +#define REG_USER_WI (1 << 2) /* WI from userspace only */ static __printf(2, 3) inline void print_sys_reg_msg(const struct sys_reg_params *p, @@ -136,22 +137,31 @@ static inline void reset_val(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r __vcpu_sys_reg(vcpu, r->reg) = r->val; } -static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu, - const struct sys_reg_desc *r) +static inline unsigned int sysreg_visibility(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) { if (likely(!r->visibility)) - return false; + return 0; - return r->visibility(vcpu, r) & REG_HIDDEN; + return r->visibility(vcpu, r); +} + +static inline bool sysreg_hidden(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) +{ + return sysreg_visibility(vcpu, r) & REG_HIDDEN; } static inline bool sysreg_visible_as_raz(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { - if (likely(!r->visibility)) - return false; + return sysreg_visibility(vcpu, r) & REG_RAZ; +} - return r->visibility(vcpu, r) & REG_RAZ; +static inline bool sysreg_user_write_ignore(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *r) +{ + return sysreg_visibility(vcpu, r) & REG_USER_WI; } static inline int cmp_sys_reg(const struct sys_reg_desc *i1, diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore index d625a3f83780..87d1a0b1bae0 100644 --- a/tools/testing/selftests/kvm/.gitignore +++ b/tools/testing/selftests/kvm/.gitignore @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only +/aarch64/aarch32_id_regs /aarch64/arch_timer /aarch64/debug-exceptions /aarch64/get-reg-list diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index 4c122f1b1737..784abe7f0962 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -144,6 +144,7 @@ TEST_GEN_PROGS_x86_64 += system_counter_offset_test # Compiled outputs used by test targets TEST_GEN_PROGS_EXTENDED_x86_64 += x86_64/nx_huge_pages_test +TEST_GEN_PROGS_aarch64 += aarch64/aarch32_id_regs TEST_GEN_PROGS_aarch64 += aarch64/arch_timer TEST_GEN_PROGS_aarch64 += aarch64/debug-exceptions TEST_GEN_PROGS_aarch64 += aarch64/get-reg-list diff --git a/tools/testing/selftests/kvm/aarch64/aarch32_id_regs.c b/tools/testing/selftests/kvm/aarch64/aarch32_id_regs.c new file mode 100644 index 000000000000..6f9c1f19c7f6 --- /dev/null +++ b/tools/testing/selftests/kvm/aarch64/aarch32_id_regs.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * aarch32_id_regs - Test for ID register behavior on AArch64-only systems + * + * Copyright (c) 2022 Google LLC. + * + * Test that KVM handles the AArch64 views of the AArch32 ID registers as RAZ + * and WI from userspace. + */ + +#include <stdint.h> + +#include "kvm_util.h" +#include "processor.h" +#include "test_util.h" + +#define BAD_ID_REG_VAL 0x1badc0deul + +#define GUEST_ASSERT_REG_RAZ(reg) GUEST_ASSERT_EQ(read_sysreg_s(reg), 0) + +static void guest_main(void) +{ + GUEST_ASSERT_REG_RAZ(SYS_ID_PFR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_PFR1_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_DFR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_AFR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR1_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR2_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR3_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR1_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR2_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR3_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR4_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR5_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR4_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_ISAR6_EL1); + GUEST_ASSERT_REG_RAZ(SYS_MVFR0_EL1); + GUEST_ASSERT_REG_RAZ(SYS_MVFR1_EL1); + GUEST_ASSERT_REG_RAZ(SYS_MVFR2_EL1); + GUEST_ASSERT_REG_RAZ(sys_reg(3, 0, 0, 3, 3)); + GUEST_ASSERT_REG_RAZ(SYS_ID_PFR2_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_DFR1_EL1); + GUEST_ASSERT_REG_RAZ(SYS_ID_MMFR5_EL1); + GUEST_ASSERT_REG_RAZ(sys_reg(3, 0, 0, 3, 7)); + + GUEST_DONE(); +} + +static void test_guest_raz(struct kvm_vcpu *vcpu) +{ + struct ucall uc; + + vcpu_run(vcpu); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + break; + case UCALL_DONE: + break; + default: + TEST_FAIL("Unexpected ucall: %lu", uc.cmd); + } +} + +static uint64_t raz_wi_reg_ids[] = { + KVM_ARM64_SYS_REG(SYS_ID_PFR0_EL1), + KVM_ARM64_SYS_REG(SYS_ID_PFR1_EL1), + KVM_ARM64_SYS_REG(SYS_ID_DFR0_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR0_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR1_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR2_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR3_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR0_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR1_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR2_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR3_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR4_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR5_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR4_EL1), + KVM_ARM64_SYS_REG(SYS_ID_ISAR6_EL1), + KVM_ARM64_SYS_REG(SYS_MVFR0_EL1), + KVM_ARM64_SYS_REG(SYS_MVFR1_EL1), + KVM_ARM64_SYS_REG(SYS_MVFR2_EL1), + KVM_ARM64_SYS_REG(SYS_ID_PFR2_EL1), + KVM_ARM64_SYS_REG(SYS_ID_MMFR5_EL1), +}; + +static void test_user_raz_wi(struct kvm_vcpu *vcpu) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(raz_wi_reg_ids); i++) { + uint64_t reg_id = raz_wi_reg_ids[i]; + uint64_t val; + + vcpu_get_reg(vcpu, reg_id, &val); + ASSERT_EQ(val, 0); + + /* + * Expect the ioctl to succeed with no effect on the register + * value. + */ + vcpu_set_reg(vcpu, reg_id, BAD_ID_REG_VAL); + + vcpu_get_reg(vcpu, reg_id, &val); + ASSERT_EQ(val, 0); + } +} + +static uint64_t raz_invariant_reg_ids[] = { + KVM_ARM64_SYS_REG(SYS_ID_AFR0_EL1), + KVM_ARM64_SYS_REG(sys_reg(3, 0, 0, 3, 3)), + KVM_ARM64_SYS_REG(SYS_ID_DFR1_EL1), + KVM_ARM64_SYS_REG(sys_reg(3, 0, 0, 3, 7)), +}; + +static void test_user_raz_invariant(struct kvm_vcpu *vcpu) +{ + int i, r; + + for (i = 0; i < ARRAY_SIZE(raz_invariant_reg_ids); i++) { + uint64_t reg_id = raz_invariant_reg_ids[i]; + uint64_t val; + + vcpu_get_reg(vcpu, reg_id, &val); + ASSERT_EQ(val, 0); + + r = __vcpu_set_reg(vcpu, reg_id, BAD_ID_REG_VAL); + TEST_ASSERT(r < 0 && errno == EINVAL, + "unexpected KVM_SET_ONE_REG error: r=%d, errno=%d", r, errno); + + vcpu_get_reg(vcpu, reg_id, &val); + ASSERT_EQ(val, 0); + } +} + + + +static bool vcpu_aarch64_only(struct kvm_vcpu *vcpu) +{ + uint64_t val, el0; + + vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), &val); + + el0 = (val & ARM64_FEATURE_MASK(ID_AA64PFR0_EL0)) >> ID_AA64PFR0_EL0_SHIFT; + return el0 == ID_AA64PFR0_ELx_64BIT_ONLY; +} + +int main(void) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + + vm = vm_create_with_one_vcpu(&vcpu, guest_main); + + TEST_REQUIRE(vcpu_aarch64_only(vcpu)); + + ucall_init(vm, NULL); + + test_user_raz_wi(vcpu); + test_user_raz_invariant(vcpu); + test_guest_raz(vcpu); + + ucall_uninit(vm); + kvm_vm_free(vm); +} |