Test successful exchange, unsuccessful exchange, storage key protection and invalid arguments.
Signed-off-by: Janis Schoetterl-Glausch scgl@linux.ibm.com --- tools/testing/selftests/kvm/s390x/memop.c | 570 +++++++++++++++++++--- 1 file changed, 495 insertions(+), 75 deletions(-)
diff --git a/tools/testing/selftests/kvm/s390x/memop.c b/tools/testing/selftests/kvm/s390x/memop.c index 311cf7d33247..3a160ab0415b 100644 --- a/tools/testing/selftests/kvm/s390x/memop.c +++ b/tools/testing/selftests/kvm/s390x/memop.c @@ -9,6 +9,7 @@ #include <stdlib.h> #include <string.h> #include <sys/ioctl.h> +#include <pthread.h>
#include <linux/bits.h>
@@ -44,10 +45,14 @@ struct mop_desc { enum mop_access_mode mode; void *buf; uint32_t sida_offset; + void *old; + bool *cmpxchg_success; uint8_t ar; uint8_t key; };
+typedef unsigned __int128 uint128; + const uint8_t NO_KEY = 0xff;
static struct kvm_s390_mem_op ksmo_from_desc(const struct mop_desc *desc) @@ -91,6 +96,26 @@ static struct kvm_s390_mem_op ksmo_from_desc(const struct mop_desc *desc) ksmo.flags |= KVM_S390_MEMOP_F_SKEY_PROTECTION; ksmo.key = desc->key; } + if (desc->old) { + ksmo.flags |= KVM_S390_MEMOP_F_CMPXCHG; + switch (ksmo.size) { + case 1: + ksmo.old[1] = *(uint8_t *)desc->old; + break; + case 2: + ksmo.old[1] = *(uint16_t *)desc->old; + break; + case 4: + ksmo.old[1] = *(uint32_t *)desc->old; + break; + case 8: + ksmo.old[1] = *(uint64_t *)desc->old; + break; + case 16: + memcpy(ksmo.old, desc->old, sizeof(ksmo.old)); + break; + } + } if (desc->_ar) ksmo.ar = desc->ar; else @@ -101,6 +126,31 @@ static struct kvm_s390_mem_op ksmo_from_desc(const struct mop_desc *desc) return ksmo; }
+static void cmpxchg_write_back(struct kvm_s390_mem_op *ksmo, struct mop_desc *desc) +{ + if (desc->old) { + switch (ksmo->size) { + case 1: + *(uint8_t *)desc->old = ksmo->old[1]; + break; + case 2: + *(uint16_t *)desc->old = ksmo->old[1]; + break; + case 4: + *(uint32_t *)desc->old = ksmo->old[1]; + break; + case 8: + *(uint64_t *)desc->old = ksmo->old[1]; + break; + case 16: + memcpy(desc->old, ksmo->old, sizeof(ksmo->old)); + break; + } + } + if (desc->cmpxchg_success) + *desc->cmpxchg_success = !(ksmo->flags & KVM_S390_MEMOP_F_CMPXCHG); +} + struct test_info { struct kvm_vm *vm; struct kvm_vcpu *vcpu; @@ -136,18 +186,22 @@ static void print_memop(struct kvm_vcpu *vcpu, const struct kvm_s390_mem_op *ksm printf("ABSOLUTE, WRITE, "); break; } - printf("gaddr=%llu, size=%u, buf=%llu, ar=%u, key=%u", - ksmo->gaddr, ksmo->size, ksmo->buf, ksmo->ar, ksmo->key); + printf("gaddr=%llu, size=%u, buf=%llu, ar=%u, key=%u, old[0]=%llu, old[1]=%llu", + ksmo->gaddr, ksmo->size, ksmo->buf, ksmo->ar, ksmo->key, + ksmo->old[0], ksmo->old[1]); if (ksmo->flags & KVM_S390_MEMOP_F_CHECK_ONLY) printf(", CHECK_ONLY"); if (ksmo->flags & KVM_S390_MEMOP_F_INJECT_EXCEPTION) printf(", INJECT_EXCEPTION"); if (ksmo->flags & KVM_S390_MEMOP_F_SKEY_PROTECTION) printf(", SKEY_PROTECTION"); + if (ksmo->flags & KVM_S390_MEMOP_F_CMPXCHG) + printf(", CMPXCHG"); puts(")"); }
-static void memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) +static void memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo, + struct mop_desc *desc) { struct kvm_vcpu *vcpu = info.vcpu;
@@ -155,16 +209,21 @@ static void memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) vm_ioctl(info.vm, KVM_S390_MEM_OP, ksmo); else vcpu_ioctl(vcpu, KVM_S390_MEM_OP, ksmo); + cmpxchg_write_back(ksmo, desc); }
-static int err_memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) +static int err_memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo, + struct mop_desc *desc) { struct kvm_vcpu *vcpu = info.vcpu; + int r;
if (!vcpu) - return __vm_ioctl(info.vm, KVM_S390_MEM_OP, ksmo); + r = __vm_ioctl(info.vm, KVM_S390_MEM_OP, ksmo); else - return __vcpu_ioctl(vcpu, KVM_S390_MEM_OP, ksmo); + r = __vcpu_ioctl(vcpu, KVM_S390_MEM_OP, ksmo); + cmpxchg_write_back(ksmo, desc); + return r; }
#define MEMOP(err, info_p, mop_target_p, access_mode_p, buf_p, size_p, ...) \ @@ -187,7 +246,7 @@ static int err_memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) } \ __ksmo = ksmo_from_desc(&__desc); \ print_memop(__info.vcpu, &__ksmo); \ - err##memop_ioctl(__info, &__ksmo); \ + err##memop_ioctl(__info, &__ksmo, &__desc); \ })
#define MOP(...) MEMOP(, __VA_ARGS__) @@ -201,6 +260,8 @@ static int err_memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) #define AR(a) ._ar = 1, .ar = (a) #define KEY(a) .f_key = 1, .key = (a) #define INJECT .f_inject = 1 +#define CMPXCHG_OLD(o) .old = (o) +#define CMPXCHG_SUCCESS(s) .cmpxchg_success = (s)
#define CHECK_N_DO(f, ...) ({ f(__VA_ARGS__, CHECK_ONLY); f(__VA_ARGS__); })
@@ -210,8 +271,8 @@ static int err_memop_ioctl(struct test_info info, struct kvm_s390_mem_op *ksmo) #define CR0_FETCH_PROTECTION_OVERRIDE (1UL << (63 - 38)) #define CR0_STORAGE_PROTECTION_OVERRIDE (1UL << (63 - 39))
-static uint8_t mem1[65536]; -static uint8_t mem2[65536]; +static uint8_t __aligned(PAGE_SIZE) mem1[65536]; +static uint8_t __aligned(PAGE_SIZE) mem2[65536];
struct test_default { struct kvm_vm *kvm_vm; @@ -243,6 +304,8 @@ enum stage { STAGE_SKEYS_SET, /* Guest copied memory (locations up to test case) */ STAGE_COPIED, + /* End of guest code reached */ + STAGE_DONE, };
#define HOST_SYNC(info_p, stage) \ @@ -254,6 +317,11 @@ enum stage { \ vcpu_run(__vcpu); \ get_ucall(__vcpu, &uc); \ + if (uc.cmd == UCALL_ABORT) { \ + TEST_FAIL("line %lu: %s, hints: %lu, %lu", \ + uc.args[1], (const char *)uc.args[0], \ + uc.args[2], uc.args[3]); \ + } \ ASSERT_EQ(uc.cmd, UCALL_SYNC); \ ASSERT_EQ(uc.args[1], __stage); \ }) \ @@ -293,6 +361,44 @@ static void default_read(struct test_info copy_cpu, struct test_info mop_cpu, ASSERT_MEM_EQ(mem1, mem2, size); }
+static void default_cmpxchg(struct test_default *test, uint8_t key) +{ + for (int size = 1; size <= 16; size *= 2) { + for (int offset = 0; offset < 16; offset += size) { + uint8_t __aligned(16) new[16] = {}; + uint8_t __aligned(16) old[16]; + bool succ; + + prepare_mem12(); + default_write_read(test->vcpu, test->vcpu, LOGICAL, 16, NO_KEY); + + memcpy(&old, mem1, 16); + CHECK_N_DO(MOP, test->vm, ABSOLUTE, WRITE, new + offset, + size, GADDR_V(mem1 + offset), + CMPXCHG_OLD(old + offset), + CMPXCHG_SUCCESS(&succ), KEY(key)); + HOST_SYNC(test->vcpu, STAGE_COPIED); + MOP(test->vm, ABSOLUTE, READ, mem2, 16, GADDR_V(mem2)); + TEST_ASSERT(succ, "exchange of values should succeed"); + memcpy(mem1 + offset, new + offset, size); + ASSERT_MEM_EQ(mem1, mem2, 16); + + memcpy(&old, mem1, 16); + new[offset]++; + old[offset]++; + CHECK_N_DO(MOP, test->vm, ABSOLUTE, WRITE, new + offset, + size, GADDR_V(mem1 + offset), + CMPXCHG_OLD(old + offset), + CMPXCHG_SUCCESS(&succ), KEY(key)); + HOST_SYNC(test->vcpu, STAGE_COPIED); + MOP(test->vm, ABSOLUTE, READ, mem2, 16, GADDR_V(mem2)); + TEST_ASSERT(!succ, "exchange of values should not succeed"); + ASSERT_MEM_EQ(mem1, mem2, 16); + ASSERT_MEM_EQ(&old, mem1, 16); + } + } +} + static void guest_copy(void) { GUEST_SYNC(STAGE_INITED); @@ -377,6 +483,250 @@ static void test_copy_key(void) kvm_vm_free(t.kvm_vm); }
+static void test_cmpxchg_key(void) +{ + struct test_default t = test_default_init(guest_copy_key); + + HOST_SYNC(t.vcpu, STAGE_SKEYS_SET); + + default_cmpxchg(&t, NO_KEY); + default_cmpxchg(&t, 0); + default_cmpxchg(&t, 9); + + kvm_vm_free(t.kvm_vm); +} + +static uint128 cut_to_size(int size, uint128 val) +{ + switch (size) { + case 1: + return (uint8_t)val; + case 2: + return (uint16_t)val; + case 4: + return (uint32_t)val; + case 8: + return (uint64_t)val; + case 16: + return val; + } + GUEST_ASSERT_1(false, "Invalid size"); + return 0; +} + +static bool popcount_eq(uint128 a, uint128 b) +{ + unsigned int count_a, count_b; + + count_a = __builtin_popcountl((uint64_t)(a >> 64)) + + __builtin_popcountl((uint64_t)a); + count_b = __builtin_popcountl((uint64_t)(b >> 64)) + + __builtin_popcountl((uint64_t)b); + return count_a == count_b; +} + +static uint128 rotate(int size, uint128 val, int amount) +{ + unsigned int bits = size * 8; + + amount = (amount + bits) % bits; + val = cut_to_size(size, val); + return (val << (bits - amount)) | (val >> amount); +} + +const unsigned int max_block = 16; + +static void choose_block(bool guest, int i, int *size, int *offset) +{ + unsigned int rand; + + rand = i; + if (guest) { + rand = rand * 19 + 11; + *size = 1 << ((rand % 3) + 2); + rand = rand * 19 + 11; + *offset = (rand % max_block) & ~(*size - 1); + } else { + rand = rand * 17 + 5; + *size = 1 << (rand % 5); + rand = rand * 17 + 5; + *offset = (rand % max_block) & ~(*size - 1); + } +} + +static uint128 permutate_bits(bool guest, int i, int size, uint128 old) +{ + unsigned int rand; + bool swap; + + rand = i; + rand = rand * 3 + 1; + if (guest) + rand = rand * 3 + 1; + swap = rand % 2 == 0; + if (swap) { + int i, j; + uint128 new; + uint8_t byte0, byte1; + + rand = rand * 3 + 1; + i = rand % size; + rand = rand * 3 + 1; + j = rand % size; + if (i == j) + return old; + new = rotate(16, old, i * 8); + byte0 = new & 0xff; + new &= ~0xff; + new = rotate(16, new, -i * 8); + new = rotate(16, new, j * 8); + byte1 = new & 0xff; + new = (new & ~0xff) | byte0; + new = rotate(16, new, -j * 8); + new = rotate(16, new, i * 8); + new = new | byte1; + new = rotate(16, new, -i * 8); + return new; + } else { + int amount; + + rand = rand * 3 + 1; + amount = rand % (size * 8); + return rotate(size, old, amount); + } +} + +static bool _cmpxchg(int size, void *target, uint128 *old_p, uint128 new) +{ + bool ret; + + switch (size) { + case 4: { + uint32_t old = *old_p; + + asm volatile ("cs %[old],%[new],%[address]" + : [old] "+d" (old), + [address] "+Q" (*(uint32_t *)(target)) + : [new] "d" ((uint32_t)new) + : "cc" + ); + ret = old == (uint32_t)*old_p; + *old_p = old; + return ret; + } + case 8: { + uint64_t old = *old_p; + + asm volatile ("csg %[old],%[new],%[address]" + : [old] "+d" (old), + [address] "+Q" (*(uint64_t *)(target)) + : [new] "d" ((uint64_t)new) + : "cc" + ); + ret = old == (uint64_t)*old_p; + *old_p = old; + return ret; + } + case 16: { + uint128 old = *old_p; + + asm volatile ("cdsg %[old],%[new],%[address]" + : [old] "+d" (old), + [address] "+Q" (*(uint128 *)(target)) + : [new] "d" (new) + : "cc" + ); + ret = old == *old_p; + *old_p = old; + return ret; + } + } + GUEST_ASSERT_1(false, "Invalid size"); + return 0; +} + +const unsigned int cmpxchg_iter_outer = 100, cmpxchg_iter_inner = 10000; + +static void guest_cmpxchg_key(void) +{ + int size, offset; + uint128 old, new; + + set_storage_key_range(mem1, max_block, 0x10); + set_storage_key_range(mem2, max_block, 0x10); + GUEST_SYNC(STAGE_SKEYS_SET); + + for (int i = 0; i < cmpxchg_iter_outer; i++) { + do { + old = 1; + } while (!_cmpxchg(16, mem1, &old, 0)); + for (int j = 0; j < cmpxchg_iter_inner; j++) { + choose_block(true, i + j, &size, &offset); + do { + new = permutate_bits(true, i + j, size, old); + } while (!_cmpxchg(size, mem2 + offset, &old, new)); + } + } + + GUEST_SYNC(STAGE_DONE); +} + +static void *run_guest(void *data) +{ + struct test_info *info = data; + + HOST_SYNC(*info, STAGE_DONE); + return NULL; +} + +static char *quad_to_char(uint128 *quad, int size) +{ + return ((char *)quad) + (sizeof(*quad) - size); +} + +static void test_cmpxchg_key_concurrent(void) +{ + struct test_default t = test_default_init(guest_cmpxchg_key); + int size, offset; + uint128 old, new; + bool success; + pthread_t thread; + + HOST_SYNC(t.vcpu, STAGE_SKEYS_SET); + prepare_mem12(); + MOP(t.vcpu, LOGICAL, WRITE, mem1, max_block, GADDR_V(mem2)); + pthread_create(&thread, NULL, run_guest, &t.vcpu); + + for (int i = 0; i < cmpxchg_iter_outer; i++) { + do { + old = 0; + new = 1; + MOP(t.vm, ABSOLUTE, WRITE, &new, + sizeof(new), GADDR_V(mem1), + CMPXCHG_OLD(&old), + CMPXCHG_SUCCESS(&success), KEY(1)); + } while (!success); + for (int j = 0; j < cmpxchg_iter_inner; j++) { + choose_block(false, i + j, &size, &offset); + do { + new = permutate_bits(false, i + j, size, old); + MOP(t.vm, ABSOLUTE, WRITE, quad_to_char(&new, size), + size, GADDR_V(mem2 + offset), + CMPXCHG_OLD(quad_to_char(&old, size)), + CMPXCHG_SUCCESS(&success), KEY(1)); + } while (!success); + } + } + + pthread_join(thread, NULL); + + MOP(t.vcpu, LOGICAL, READ, mem2, max_block, GADDR_V(mem2)); + TEST_ASSERT(popcount_eq(*(uint128 *)mem1, *(uint128 *)mem2), + "Must retain number of set bits"); + + kvm_vm_free(t.kvm_vm); +} + static void guest_copy_key_fetch_prot(void) { /* @@ -457,6 +807,24 @@ static void test_errors_key(void) kvm_vm_free(t.kvm_vm); }
+static void test_errors_cmpxchg_key(void) +{ + struct test_default t = test_default_init(guest_copy_key_fetch_prot); + int i; + + HOST_SYNC(t.vcpu, STAGE_INITED); + HOST_SYNC(t.vcpu, STAGE_SKEYS_SET); + + for (i = 1; i <= 16; i *= 2) { + uint128 old = 0; + + CHECK_N_DO(ERR_PROT_MOP, t.vm, ABSOLUTE, WRITE, mem2, i, GADDR_V(mem2), + CMPXCHG_OLD(&old), KEY(2)); + } + + kvm_vm_free(t.kvm_vm); +} + static void test_termination(void) { struct test_default t = test_default_init(guest_error_key); @@ -692,87 +1060,139 @@ static void test_errors(void) kvm_vm_free(t.kvm_vm); }
-struct testdef { - const char *name; - void (*test)(void); - int extension; -} testlist[] = { - { - .name = "simple copy", - .test = test_copy, - }, - { - .name = "generic error checks", - .test = test_errors, - }, - { - .name = "copy with storage keys", - .test = test_copy_key, - .extension = 1, - }, - { - .name = "copy with key storage protection override", - .test = test_copy_key_storage_prot_override, - .extension = 1, - }, - { - .name = "copy with key fetch protection", - .test = test_copy_key_fetch_prot, - .extension = 1, - }, - { - .name = "copy with key fetch protection override", - .test = test_copy_key_fetch_prot_override, - .extension = 1, - }, - { - .name = "error checks with key", - .test = test_errors_key, - .extension = 1, - }, - { - .name = "termination", - .test = test_termination, - .extension = 1, - }, - { - .name = "error checks with key storage protection override", - .test = test_errors_key_storage_prot_override, - .extension = 1, - }, - { - .name = "error checks without key fetch prot override", - .test = test_errors_key_fetch_prot_override_not_enabled, - .extension = 1, - }, - { - .name = "error checks with key fetch prot override", - .test = test_errors_key_fetch_prot_override_enabled, - .extension = 1, - }, -}; +static void test_errors_cmpxchg(void) +{ + struct test_default t = test_default_init(guest_idle); + uint128 old; + int rv, i, power = 1; + + HOST_SYNC(t.vcpu, STAGE_INITED); + + for (i = 0; i < 32; i++) { + if (i == power) { + power *= 2; + continue; + } + rv = ERR_MOP(t.vm, ABSOLUTE, WRITE, mem1, i, GADDR_V(mem1), + CMPXCHG_OLD(&old)); + TEST_ASSERT(rv == -1 && errno == EINVAL, + "ioctl allows bad size for cmpxchg"); + } + for (i = 1; i <= 16; i *= 2) { + rv = ERR_MOP(t.vm, ABSOLUTE, WRITE, mem1, i, GADDR((void *)~0xfffUL), + CMPXCHG_OLD(&old)); + TEST_ASSERT(rv > 0, "ioctl allows bad guest address for cmpxchg"); + } + for (i = 2; i <= 16; i *= 2) { + rv = ERR_MOP(t.vm, ABSOLUTE, WRITE, mem1, i, GADDR_V(mem1 + 1), + CMPXCHG_OLD(&old)); + TEST_ASSERT(rv == -1 && errno == EINVAL, + "ioctl allows bad alignment for cmpxchg"); + } + + kvm_vm_free(t.kvm_vm); +}
int main(int argc, char *argv[]) { int extension_cap, idx;
+ setbuf(stdout, NULL); /* Tell stdout not to buffer its content */ TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_MEM_OP)); + extension_cap = kvm_check_cap(KVM_CAP_S390_MEM_OP_EXTENSION);
- setbuf(stdout, NULL); /* Tell stdout not to buffer its content */ + struct testdef { + const char *name; + void (*test)(void); + bool requirements_met; + } testlist[] = { + { + .name = "simple copy", + .test = test_copy, + .requirements_met = true, + }, + { + .name = "generic error checks", + .test = test_errors, + .requirements_met = true, + }, + { + .name = "copy with storage keys", + .test = test_copy_key, + .requirements_met = extension_cap > 0, + }, + { + .name = "cmpxchg with storage keys", + .test = test_cmpxchg_key, + .requirements_met = extension_cap & 0x2, + }, + { + .name = "concurrently cmpxchg with storage keys", + .test = test_cmpxchg_key_concurrent, + .requirements_met = extension_cap & 0x2, + }, + { + .name = "copy with key storage protection override", + .test = test_copy_key_storage_prot_override, + .requirements_met = extension_cap > 0, + }, + { + .name = "copy with key fetch protection", + .test = test_copy_key_fetch_prot, + .requirements_met = extension_cap > 0, + }, + { + .name = "copy with key fetch protection override", + .test = test_copy_key_fetch_prot_override, + .requirements_met = extension_cap > 0, + }, + { + .name = "error checks with key", + .test = test_errors_key, + .requirements_met = extension_cap > 0, + }, + { + .name = "error checks for cmpxchg with key", + .test = test_errors_cmpxchg_key, + .requirements_met = extension_cap & 0x2, + }, + { + .name = "error checks for cmpxchg", + .test = test_errors_cmpxchg, + .requirements_met = extension_cap & 0x2, + }, + { + .name = "termination", + .test = test_termination, + .requirements_met = extension_cap > 0, + }, + { + .name = "error checks with key storage protection override", + .test = test_errors_key_storage_prot_override, + .requirements_met = extension_cap > 0, + }, + { + .name = "error checks without key fetch prot override", + .test = test_errors_key_fetch_prot_override_not_enabled, + .requirements_met = extension_cap > 0, + }, + { + .name = "error checks with key fetch prot override", + .test = test_errors_key_fetch_prot_override_enabled, + .requirements_met = extension_cap > 0, + }, + };
ksft_print_header(); - ksft_set_plan(ARRAY_SIZE(testlist));
- extension_cap = kvm_check_cap(KVM_CAP_S390_MEM_OP_EXTENSION); for (idx = 0; idx < ARRAY_SIZE(testlist); idx++) { - if (extension_cap >= testlist[idx].extension) { + if (testlist[idx].requirements_met) { testlist[idx].test(); ksft_test_result_pass("%s\n", testlist[idx].name); } else { - ksft_test_result_skip("%s - extension level %d not supported\n", - testlist[idx].name, - testlist[idx].extension); + ksft_test_result_skip("%s - requirements not met (kernel has extension cap %#x\n)", + testlist[idx].name, extension_cap); } }