diff options
Diffstat (limited to 'tools/testing/selftests/kvm/x86_64/amx_test.c')
| -rw-r--r-- | tools/testing/selftests/kvm/x86_64/amx_test.c | 364 |
1 files changed, 364 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c new file mode 100644 index 000000000..bd72c6eb3 --- /dev/null +++ b/tools/testing/selftests/kvm/x86_64/amx_test.c @@ -0,0 +1,364 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * amx tests + * + * Copyright (C) 2021, Intel, Inc. + * + * Tests for amx #NM exception and save/restore. + */ + +#define _GNU_SOURCE /* for program_invocation_short_name */ +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/ioctl.h> +#include <sys/syscall.h> + +#include "test_util.h" + +#include "kvm_util.h" +#include "processor.h" +#include "vmx.h" + +#ifndef __x86_64__ +# error This test is 64-bit only +#endif + +#define NUM_TILES 8 +#define TILE_SIZE 1024 +#define XSAVE_SIZE ((NUM_TILES * TILE_SIZE) + PAGE_SIZE) + +/* Tile configuration associated: */ +#define MAX_TILES 16 +#define RESERVED_BYTES 14 + +#define XFEATURE_XTILECFG 17 +#define XFEATURE_XTILEDATA 18 +#define XFEATURE_MASK_XTILECFG (1 << XFEATURE_XTILECFG) +#define XFEATURE_MASK_XTILEDATA (1 << XFEATURE_XTILEDATA) +#define XFEATURE_MASK_XTILE (XFEATURE_MASK_XTILECFG | XFEATURE_MASK_XTILEDATA) + +#define XSAVE_HDR_OFFSET 512 + +struct xsave_data { + u8 area[XSAVE_SIZE]; +} __aligned(64); + +struct tile_config { + u8 palette_id; + u8 start_row; + u8 reserved[RESERVED_BYTES]; + u16 colsb[MAX_TILES]; + u8 rows[MAX_TILES]; +}; + +struct tile_data { + u8 data[NUM_TILES * TILE_SIZE]; +}; + +struct xtile_info { + u16 bytes_per_tile; + u16 bytes_per_row; + u16 max_names; + u16 max_rows; + u32 xsave_offset; + u32 xsave_size; +}; + +static struct xtile_info xtile; + +static inline u64 __xgetbv(u32 index) +{ + u32 eax, edx; + + asm volatile("xgetbv;" + : "=a" (eax), "=d" (edx) + : "c" (index)); + return eax + ((u64)edx << 32); +} + +static inline void __xsetbv(u32 index, u64 value) +{ + u32 eax = value; + u32 edx = value >> 32; + + asm volatile("xsetbv" :: "a" (eax), "d" (edx), "c" (index)); +} + +static inline void __ldtilecfg(void *cfg) +{ + asm volatile(".byte 0xc4,0xe2,0x78,0x49,0x00" + : : "a"(cfg)); +} + +static inline void __tileloadd(void *tile) +{ + asm volatile(".byte 0xc4,0xe2,0x7b,0x4b,0x04,0x10" + : : "a"(tile), "d"(0)); +} + +static inline void __tilerelease(void) +{ + asm volatile(".byte 0xc4, 0xe2, 0x78, 0x49, 0xc0" ::); +} + +static inline void __xsavec(struct xsave_data *data, uint64_t rfbm) +{ + uint32_t rfbm_lo = rfbm; + uint32_t rfbm_hi = rfbm >> 32; + + asm volatile("xsavec (%%rdi)" + : : "D" (data), "a" (rfbm_lo), "d" (rfbm_hi) + : "memory"); +} + +static inline void check_cpuid_xsave(void) +{ + GUEST_ASSERT(this_cpu_has(X86_FEATURE_XSAVE)); + GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE)); +} + +static bool check_xsave_supports_xtile(void) +{ + return __xgetbv(0) & XFEATURE_MASK_XTILE; +} + +static void check_xtile_info(void) +{ + GUEST_ASSERT(this_cpu_has_p(X86_PROPERTY_XSTATE_MAX_SIZE_XCR0)); + GUEST_ASSERT(this_cpu_property(X86_PROPERTY_XSTATE_MAX_SIZE_XCR0) <= XSAVE_SIZE); + + xtile.xsave_offset = this_cpu_property(X86_PROPERTY_XSTATE_TILE_OFFSET); + GUEST_ASSERT(xtile.xsave_offset == 2816); + xtile.xsave_size = this_cpu_property(X86_PROPERTY_XSTATE_TILE_SIZE); + GUEST_ASSERT(xtile.xsave_size == 8192); + GUEST_ASSERT(sizeof(struct tile_data) >= xtile.xsave_size); + + GUEST_ASSERT(this_cpu_has_p(X86_PROPERTY_AMX_NR_TILE_REGS)); + xtile.max_names = this_cpu_property(X86_PROPERTY_AMX_NR_TILE_REGS); + GUEST_ASSERT(xtile.max_names == 8); + xtile.bytes_per_tile = this_cpu_property(X86_PROPERTY_AMX_BYTES_PER_TILE); + GUEST_ASSERT(xtile.bytes_per_tile == 1024); + xtile.bytes_per_row = this_cpu_property(X86_PROPERTY_AMX_BYTES_PER_ROW); + GUEST_ASSERT(xtile.bytes_per_row == 64); + xtile.max_rows = this_cpu_property(X86_PROPERTY_AMX_MAX_ROWS); + GUEST_ASSERT(xtile.max_rows == 16); +} + +static void set_tilecfg(struct tile_config *cfg) +{ + int i; + + /* Only palette id 1 */ + cfg->palette_id = 1; + for (i = 0; i < xtile.max_names; i++) { + cfg->colsb[i] = xtile.bytes_per_row; + cfg->rows[i] = xtile.max_rows; + } +} + +static void set_xstatebv(void *data, uint64_t bv) +{ + *(uint64_t *)(data + XSAVE_HDR_OFFSET) = bv; +} + +static u64 get_xstatebv(void *data) +{ + return *(u64 *)(data + XSAVE_HDR_OFFSET); +} + +static void init_regs(void) +{ + uint64_t cr4, xcr0; + + /* turn on CR4.OSXSAVE */ + cr4 = get_cr4(); + cr4 |= X86_CR4_OSXSAVE; + set_cr4(cr4); + + xcr0 = __xgetbv(0); + xcr0 |= XFEATURE_MASK_XTILE; + __xsetbv(0x0, xcr0); +} + +static void __attribute__((__flatten__)) guest_code(struct tile_config *amx_cfg, + struct tile_data *tiledata, + struct xsave_data *xsave_data) +{ + init_regs(); + check_cpuid_xsave(); + check_xsave_supports_xtile(); + check_xtile_info(); + GUEST_SYNC(1); + + /* xfd=0, enable amx */ + wrmsr(MSR_IA32_XFD, 0); + GUEST_SYNC(2); + GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == 0); + set_tilecfg(amx_cfg); + __ldtilecfg(amx_cfg); + GUEST_SYNC(3); + /* Check save/restore when trap to userspace */ + __tileloadd(tiledata); + GUEST_SYNC(4); + __tilerelease(); + GUEST_SYNC(5); + /* bit 18 not in the XCOMP_BV after xsavec() */ + set_xstatebv(xsave_data, XFEATURE_MASK_XTILEDATA); + __xsavec(xsave_data, XFEATURE_MASK_XTILEDATA); + GUEST_ASSERT((get_xstatebv(xsave_data) & XFEATURE_MASK_XTILEDATA) == 0); + + /* xfd=0x40000, disable amx tiledata */ + wrmsr(MSR_IA32_XFD, XFEATURE_MASK_XTILEDATA); + GUEST_SYNC(6); + GUEST_ASSERT(rdmsr(MSR_IA32_XFD) == XFEATURE_MASK_XTILEDATA); + set_tilecfg(amx_cfg); + __ldtilecfg(amx_cfg); + /* Trigger #NM exception */ + __tileloadd(tiledata); + GUEST_SYNC(10); + + GUEST_DONE(); +} + +void guest_nm_handler(struct ex_regs *regs) +{ + /* Check if #NM is triggered by XFEATURE_MASK_XTILEDATA */ + GUEST_SYNC(7); + GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); + GUEST_SYNC(8); + GUEST_ASSERT(rdmsr(MSR_IA32_XFD_ERR) == XFEATURE_MASK_XTILEDATA); + /* Clear xfd_err */ + wrmsr(MSR_IA32_XFD_ERR, 0); + /* xfd=0, enable amx */ + wrmsr(MSR_IA32_XFD, 0); + GUEST_SYNC(9); +} + +int main(int argc, char *argv[]) +{ + struct kvm_regs regs1, regs2; + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + struct kvm_run *run; + struct kvm_x86_state *state; + int xsave_restore_size; + vm_vaddr_t amx_cfg, tiledata, xsavedata; + struct ucall uc; + u32 amx_offset; + int stage, ret; + + /* + * Note, all off-by-default features must be enabled before anything + * caches KVM_GET_SUPPORTED_CPUID, e.g. before using kvm_cpu_has(). + */ + vm_xsave_require_permission(XSTATE_XTILE_DATA_BIT); + + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XFD)); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVE)); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_AMX_TILE)); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XTILECFG)); + TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XTILEDATA)); + + /* Create VM */ + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + + TEST_ASSERT(kvm_cpu_has_p(X86_PROPERTY_XSTATE_MAX_SIZE), + "KVM should enumerate max XSAVE size when XSAVE is supported"); + xsave_restore_size = kvm_cpu_property(X86_PROPERTY_XSTATE_MAX_SIZE); + + run = vcpu->run; + vcpu_regs_get(vcpu, ®s1); + + /* Register #NM handler */ + vm_init_descriptor_tables(vm); + vcpu_init_descriptor_tables(vcpu); + vm_install_exception_handler(vm, NM_VECTOR, guest_nm_handler); + + /* amx cfg for guest_code */ + amx_cfg = vm_vaddr_alloc_page(vm); + memset(addr_gva2hva(vm, amx_cfg), 0x0, getpagesize()); + + /* amx tiledata for guest_code */ + tiledata = vm_vaddr_alloc_pages(vm, 2); + memset(addr_gva2hva(vm, tiledata), rand() | 1, 2 * getpagesize()); + + /* xsave data for guest_code */ + xsavedata = vm_vaddr_alloc_pages(vm, 3); + memset(addr_gva2hva(vm, xsavedata), 0, 3 * getpagesize()); + vcpu_args_set(vcpu, 3, amx_cfg, tiledata, xsavedata); + + for (stage = 1; ; stage++) { + vcpu_run(vcpu); + TEST_ASSERT(run->exit_reason == KVM_EXIT_IO, + "Stage %d: unexpected exit reason: %u (%s),\n", + stage, run->exit_reason, + exit_reason_str(run->exit_reason)); + + switch (get_ucall(vcpu, &uc)) { + case UCALL_ABORT: + REPORT_GUEST_ASSERT(uc); + /* NOT REACHED */ + case UCALL_SYNC: + switch (uc.args[1]) { + case 1: + case 2: + case 3: + case 5: + case 6: + case 7: + case 8: + fprintf(stderr, "GUEST_SYNC(%ld)\n", uc.args[1]); + break; + case 4: + case 10: + fprintf(stderr, + "GUEST_SYNC(%ld), check save/restore status\n", uc.args[1]); + + /* Compacted mode, get amx offset by xsave area + * size subtract 8K amx size. + */ + amx_offset = xsave_restore_size - NUM_TILES*TILE_SIZE; + state = vcpu_save_state(vcpu); + void *amx_start = (void *)state->xsave + amx_offset; + void *tiles_data = (void *)addr_gva2hva(vm, tiledata); + /* Only check TMM0 register, 1 tile */ + ret = memcmp(amx_start, tiles_data, TILE_SIZE); + TEST_ASSERT(ret == 0, "memcmp failed, ret=%d\n", ret); + kvm_x86_state_cleanup(state); + break; + case 9: + fprintf(stderr, + "GUEST_SYNC(%ld), #NM exception and enable amx\n", uc.args[1]); + break; + } + break; + case UCALL_DONE: + fprintf(stderr, "UCALL_DONE\n"); + goto done; + default: + TEST_FAIL("Unknown ucall %lu", uc.cmd); + } + + state = vcpu_save_state(vcpu); + memset(®s1, 0, sizeof(regs1)); + vcpu_regs_get(vcpu, ®s1); + + kvm_vm_release(vm); + + /* Restore state in a new VM. */ + vcpu = vm_recreate_with_one_vcpu(vm); + vcpu_load_state(vcpu, state); + run = vcpu->run; + kvm_x86_state_cleanup(state); + + memset(®s2, 0, sizeof(regs2)); + vcpu_regs_get(vcpu, ®s2); + TEST_ASSERT(!memcmp(®s1, ®s2, sizeof(regs2)), + "Unexpected register values after vcpu_load_state; rdi: %lx rsi: %lx", + (ulong) regs2.rdi, (ulong) regs2.rsi); + } +done: + kvm_vm_free(vm); +} |