/*- * SPDX-License-Identifier: BSD-2-Clause-FreeBSD * * Copyright (c) 2011 NetApp, Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ /* * This file and its contents are supplied under the terms of the * Common Development and Distribution License ("CDDL"), version 1.0. * You may only use this file in accordance with the terms of version * 1.0 of the CDDL. * * A full copy of the text of the CDDL should have accompanied this * source. A copy of the CDDL is also available via the Internet at * http://www.illumos.org/license/CDDL. * * Copyright 2014 Pluribus Networks Inc. * Copyright 2018 Joyent, Inc. * Copyright 2020 Oxide Computer Company */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include "vmm_host.h" #include "vmm_util.h" SYSCTL_DECL(_hw_vmm); #define CPUID_VM_HIGH 0x40000000 static const char bhyve_id[12] = "bhyve bhyve "; /* Number of times an unknown cpuid leaf was accessed */ static uint64_t bhyve_xcpuids; static int cpuid_leaf_b = 1; /* * Force exposition of the invariant TSC capability, regardless of whether the * host CPU reports having it. */ static int vmm_force_invariant_tsc = 0; #define CPUID_0000_0000 (0x0) #define CPUID_0000_0001 (0x1) #define CPUID_0000_0002 (0x2) #define CPUID_0000_0003 (0x3) #define CPUID_0000_0004 (0x4) #define CPUID_0000_0006 (0x6) #define CPUID_0000_0007 (0x7) #define CPUID_0000_000A (0xA) #define CPUID_0000_000B (0xB) #define CPUID_0000_000D (0xD) #define CPUID_0000_000F (0xF) #define CPUID_0000_0010 (0x10) #define CPUID_0000_0015 (0x15) #define CPUID_8000_0000 (0x80000000) #define CPUID_8000_0001 (0x80000001) #define CPUID_8000_0002 (0x80000002) #define CPUID_8000_0003 (0x80000003) #define CPUID_8000_0004 (0x80000004) #define CPUID_8000_0006 (0x80000006) #define CPUID_8000_0007 (0x80000007) #define CPUID_8000_0008 (0x80000008) #define CPUID_8000_001D (0x8000001D) #define CPUID_8000_001E (0x8000001E) /* * CPUID instruction Fn0000_0001: */ #define CPUID_0000_0001_APICID_MASK (0xff<<24) #define CPUID_0000_0001_APICID_SHIFT 24 /* * CPUID instruction Fn0000_0001 ECX */ #define CPUID_0000_0001_FEAT0_VMX (1<<5) /* * Round up to the next power of two, if necessary, and then take log2. * Returns -1 if argument is zero. */ static __inline int log2(uint_t x) { return (fls(x << (1 - powerof2(x))) - 1); } int x86_emulate_cpuid(struct vm *vm, int vcpu_id, uint64_t *rax, uint64_t *rbx, uint64_t *rcx, uint64_t *rdx) { const struct xsave_limits *limits; uint64_t cr4; int error, enable_invpcid, level, width = 0, x2apic_id = 0; unsigned int func, regs[4], logical_cpus = 0, param; enum x2apic_state x2apic_state; uint16_t cores, maxcpus, sockets, threads; /* * The function of CPUID is controlled through the provided value of * %eax (and secondarily %ecx, for certain leaf data). */ func = (uint32_t)*rax; param = (uint32_t)*rcx; /* * Requests for invalid CPUID levels should map to the highest * available level instead. */ if (cpu_exthigh != 0 && func >= 0x80000000) { if (func > cpu_exthigh) func = cpu_exthigh; } else if (func >= 0x40000000) { if (func > CPUID_VM_HIGH) func = CPUID_VM_HIGH; } else if (func > cpu_high) { func = cpu_high; } /* * In general the approach used for CPU topology is to * advertise a flat topology where all CPUs are packages with * no multi-core or SMT. */ switch (func) { /* * Pass these through to the guest */ case CPUID_0000_0000: case CPUID_0000_0002: case CPUID_0000_0003: case CPUID_8000_0000: case CPUID_8000_0002: case CPUID_8000_0003: case CPUID_8000_0004: case CPUID_8000_0006: cpuid_count(func, param, regs); break; case CPUID_8000_0008: cpuid_count(func, param, regs); if (vmm_is_svm()) { /* * As on Intel (0000_0007:0, EDX), mask out * unsupported or unsafe AMD extended features * (8000_0008 EBX). */ regs[1] &= (AMDFEID_CLZERO | AMDFEID_IRPERF | AMDFEID_XSAVEERPTR); vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); /* * Here, width is ApicIdCoreIdSize, present on * at least Family 15h and newer. It * represents the "number of bits in the * initial apicid that indicate thread id * within a package." * * Our topo_probe_amd() uses it for * pkg_id_shift and other OSes may rely on it. */ width = MIN(0xF, log2(threads * cores)); if (width < 0x4) width = 0; logical_cpus = MIN(0xFF, threads * cores - 1); regs[2] = (width << AMDID_COREID_SIZE_SHIFT) | logical_cpus; } break; case CPUID_8000_0001: cpuid_count(func, param, regs); /* * Hide SVM from guest. */ regs[2] &= ~AMDID2_SVM; /* * Don't advertise extended performance counter MSRs * to the guest. */ regs[2] &= ~AMDID2_PCXC; regs[2] &= ~AMDID2_PNXC; regs[2] &= ~AMDID2_PTSCEL2I; /* * Don't advertise Instruction Based Sampling feature. */ regs[2] &= ~AMDID2_IBS; /* NodeID MSR not available */ regs[2] &= ~AMDID2_NODE_ID; /* Don't advertise the OS visible workaround feature */ regs[2] &= ~AMDID2_OSVW; /* Hide mwaitx/monitorx capability from the guest */ regs[2] &= ~AMDID2_MWAITX; #ifndef __FreeBSD__ /* * Detection routines for TCE and FFXSR are missing * from our vm_cpuid_capability() detection logic * today. Mask them out until that is remedied. * They do not appear to be in common usage, so their * absence should not cause undue trouble. */ regs[2] &= ~AMDID2_TCE; regs[3] &= ~AMDID_FFXSR; #endif /* * Hide rdtscp/ia32_tsc_aux until we know how * to deal with them. */ regs[3] &= ~AMDID_RDTSCP; break; case CPUID_8000_0007: cpuid_count(func, param, regs); /* * AMD uses this leaf to advertise the processor's * power monitoring and RAS capabilities. These * features are hardware-specific and exposing * them to a guest doesn't make a lot of sense. * * Intel uses this leaf only to advertise the * "Invariant TSC" feature with all other bits * being reserved (set to zero). */ regs[0] = 0; regs[1] = 0; regs[2] = 0; /* * If the host system possesses an invariant TSC, then * it is safe to expose to the guest. * * If there is measured skew between host TSCs, it will * be properly offset so guests do not observe any * change between CPU migrations. */ regs[3] &= AMDPM_TSC_INVARIANT; /* * Since illumos avoids deep C-states on CPUs which do * not support an invariant TSC, it may be safe (and * desired) to unconditionally expose that capability to * the guest. */ if (vmm_force_invariant_tsc != 0) { regs[3] |= AMDPM_TSC_INVARIANT; } break; case CPUID_8000_001D: /* AMD Cache topology, like 0000_0004 for Intel. */ if (!vmm_is_svm()) goto default_leaf; /* * Similar to Intel, generate a ficticious cache * topology for the guest with L3 shared by the * package, and L1 and L2 local to a core. */ vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); switch (param) { case 0: logical_cpus = threads; level = 1; func = 1; /* data cache */ break; case 1: logical_cpus = threads; level = 2; func = 3; /* unified cache */ break; case 2: logical_cpus = threads * cores; level = 3; func = 3; /* unified cache */ break; default: logical_cpus = 0; level = 0; func = 0; break; } logical_cpus = MIN(0xfff, logical_cpus - 1); regs[0] = (logical_cpus << 14) | (1 << 8) | (level << 5) | func; regs[1] = (func > 0) ? (CACHE_LINE_SIZE - 1) : 0; regs[2] = 0; regs[3] = 0; break; case CPUID_8000_001E: /* * AMD Family 16h+ and Hygon Family 18h additional * identifiers. */ if (!vmm_is_svm() || CPUID_TO_FAMILY(cpu_id) < 0x16) goto default_leaf; vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); regs[0] = vcpu_id; threads = MIN(0xFF, threads - 1); regs[1] = (threads << 8) | (vcpu_id >> log2(threads + 1)); /* * XXX Bhyve topology cannot yet represent >1 node per * processor. */ regs[2] = 0; regs[3] = 0; break; case CPUID_0000_0001: do_cpuid(1, regs); error = vm_get_x2apic_state(vm, vcpu_id, &x2apic_state); if (error) { panic("x86_emulate_cpuid: error %d " "fetching x2apic state", error); } /* * Override the APIC ID only in ebx */ regs[1] &= ~(CPUID_LOCAL_APIC_ID); regs[1] |= (vcpu_id << CPUID_0000_0001_APICID_SHIFT); /* * Don't expose VMX, SpeedStep, TME or SMX capability. * Advertise x2APIC capability and Hypervisor guest. */ regs[2] &= ~(CPUID2_VMX | CPUID2_EST | CPUID2_TM2); regs[2] &= ~(CPUID2_SMX); regs[2] |= CPUID2_HV; if (x2apic_state != X2APIC_DISABLED) regs[2] |= CPUID2_X2APIC; else regs[2] &= ~CPUID2_X2APIC; /* * Only advertise CPUID2_XSAVE in the guest if * the host is using XSAVE. */ if (!(regs[2] & CPUID2_OSXSAVE)) regs[2] &= ~CPUID2_XSAVE; /* * If CPUID2_XSAVE is being advertised and the * guest has set CR4_XSAVE, set * CPUID2_OSXSAVE. */ regs[2] &= ~CPUID2_OSXSAVE; if (regs[2] & CPUID2_XSAVE) { error = vm_get_register(vm, vcpu_id, VM_REG_GUEST_CR4, &cr4); if (error) panic("x86_emulate_cpuid: error %d " "fetching %%cr4", error); if (cr4 & CR4_XSAVE) regs[2] |= CPUID2_OSXSAVE; } /* * Hide monitor/mwait until we know how to deal with * these instructions. */ regs[2] &= ~CPUID2_MON; /* * Hide the performance and debug features. */ regs[2] &= ~CPUID2_PDCM; /* * No TSC deadline support in the APIC yet */ regs[2] &= ~CPUID2_TSCDLT; /* * Hide thermal monitoring */ regs[3] &= ~(CPUID_ACPI | CPUID_TM); /* * Hide the debug store capability. */ regs[3] &= ~CPUID_DS; /* * Advertise the Machine Check and MTRR capability. * * Some guest OSes (e.g. Windows) will not boot if * these features are absent. */ regs[3] |= (CPUID_MCA | CPUID_MCE | CPUID_MTRR); vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); logical_cpus = threads * cores; regs[1] &= ~CPUID_HTT_CORES; regs[1] |= (logical_cpus & 0xff) << 16; regs[3] |= CPUID_HTT; break; case CPUID_0000_0004: cpuid_count(func, param, regs); if (regs[0] || regs[1] || regs[2] || regs[3]) { vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); regs[0] &= 0x3ff; regs[0] |= (cores - 1) << 26; /* * Cache topology: * - L1 and L2 are shared only by the logical * processors in a single core. * - L3 and above are shared by all logical * processors in the package. */ logical_cpus = threads; level = (regs[0] >> 5) & 0x7; if (level >= 3) logical_cpus *= cores; regs[0] |= (logical_cpus - 1) << 14; } break; case CPUID_0000_0007: regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; /* leaf 0 */ if (param == 0) { cpuid_count(func, param, regs); /* Only leaf 0 is supported */ regs[0] = 0; /* * Expose known-safe features. */ regs[1] &= (CPUID_STDEXT_FSGSBASE | CPUID_STDEXT_BMI1 | CPUID_STDEXT_HLE | CPUID_STDEXT_AVX2 | CPUID_STDEXT_SMEP | CPUID_STDEXT_BMI2 | CPUID_STDEXT_ERMS | CPUID_STDEXT_RTM | CPUID_STDEXT_AVX512F | CPUID_STDEXT_RDSEED | CPUID_STDEXT_SMAP | CPUID_STDEXT_AVX512PF | CPUID_STDEXT_AVX512ER | CPUID_STDEXT_AVX512CD | CPUID_STDEXT_SHA); regs[2] = 0; regs[3] &= CPUID_STDEXT3_MD_CLEAR; /* Advertise INVPCID if it is enabled. */ error = vm_get_capability(vm, vcpu_id, VM_CAP_ENABLE_INVPCID, &enable_invpcid); if (error == 0 && enable_invpcid) regs[1] |= CPUID_STDEXT_INVPCID; } break; case CPUID_0000_0006: regs[0] = CPUTPM1_ARAT; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; case CPUID_0000_000A: /* * Handle the access, but report 0 for * all options */ regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; case CPUID_0000_000B: /* * Intel processor topology enumeration */ if (vmm_is_intel()) { vm_get_topology(vm, &sockets, &cores, &threads, &maxcpus); if (param == 0) { logical_cpus = threads; width = log2(logical_cpus); level = CPUID_TYPE_SMT; x2apic_id = vcpu_id; } if (param == 1) { logical_cpus = threads * cores; width = log2(logical_cpus); level = CPUID_TYPE_CORE; x2apic_id = vcpu_id; } if (!cpuid_leaf_b || param >= 2) { width = 0; logical_cpus = 0; level = 0; x2apic_id = 0; } regs[0] = width & 0x1f; regs[1] = logical_cpus & 0xffff; regs[2] = (level << 8) | (param & 0xff); regs[3] = x2apic_id; } else { regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; } break; case CPUID_0000_000D: limits = vmm_get_xsave_limits(); if (!limits->xsave_enabled) { regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; } cpuid_count(func, param, regs); switch (param) { case 0: /* * Only permit the guest to use bits * that are active in the host in * %xcr0. Also, claim that the * maximum save area size is * equivalent to the host's current * save area size. Since this runs * "inside" of vmrun(), it runs with * the guest's xcr0, so the current * save area size is correct as-is. */ regs[0] &= limits->xcr0_allowed; regs[2] = limits->xsave_max_size; regs[3] &= (limits->xcr0_allowed >> 32); break; case 1: /* Only permit XSAVEOPT. */ regs[0] &= CPUID_EXTSTATE_XSAVEOPT; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; default: /* * If the leaf is for a permitted feature, * pass through as-is, otherwise return * all zeroes. */ if (!(limits->xcr0_allowed & (1ul << param))) { regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; } break; } break; case CPUID_0000_000F: case CPUID_0000_0010: /* * Do not report any Resource Director Technology * capabilities. Exposing control of cache or memory * controller resource partitioning to the guest is not * at all sensible. * * This is already hidden at a high level by masking of * leaf 0x7. Even still, a guest may look here for * detailed capability information. */ regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; case CPUID_0000_0015: /* * Don't report CPU TSC/Crystal ratio and clock * values since guests may use these to derive the * local APIC frequency.. */ regs[0] = 0; regs[1] = 0; regs[2] = 0; regs[3] = 0; break; case 0x40000000: regs[0] = CPUID_VM_HIGH; bcopy(bhyve_id, ®s[1], 4); bcopy(bhyve_id + 4, ®s[2], 4); bcopy(bhyve_id + 8, ®s[3], 4); break; default: default_leaf: /* * The leaf value has already been clamped so * simply pass this through, keeping count of * how many unhandled leaf values have been seen. */ atomic_add_long(&bhyve_xcpuids, 1); cpuid_count(func, param, regs); break; } /* * CPUID clears the upper 32-bits of the long-mode registers. */ *rax = regs[0]; *rbx = regs[1]; *rcx = regs[2]; *rdx = regs[3]; return (1); } /* * Return 'true' if the capability 'cap' is enabled in this virtual cpu * and 'false' otherwise. */ bool vm_cpuid_capability(struct vm *vm, int vcpuid, enum vm_cpuid_capability cap) { bool rv; KASSERT(cap > 0 && cap < VCC_LAST, ("%s: invalid vm_cpu_capability %d", __func__, cap)); /* * Simply passthrough the capabilities of the host cpu for now. */ rv = false; switch (cap) { #ifdef __FreeBSD__ case VCC_NO_EXECUTE: if (amd_feature & AMDID_NX) rv = true; break; case VCC_FFXSR: if (amd_feature & AMDID_FFXSR) rv = true; break; case VCC_TCE: if (amd_feature2 & AMDID2_TCE) rv = true; break; #else case VCC_NO_EXECUTE: if (is_x86_feature(x86_featureset, X86FSET_NX)) rv = true; break; /* XXXJOY: No kernel detection for FFXR or TCE at present, so ignore */ case VCC_FFXSR: case VCC_TCE: break; #endif default: panic("%s: unknown vm_cpu_capability %d", __func__, cap); } return (rv); } bool validate_guest_xcr0(uint64_t val, uint64_t limit_mask) { /* x87 feature must be enabled */ if ((val & XFEATURE_ENABLED_X87) == 0) { return (false); } /* AVX cannot be enabled without SSE */ if ((val & (XFEATURE_ENABLED_SSE | XFEATURE_ENABLED_AVX)) == XFEATURE_ENABLED_SSE) { return (false); } /* No bits should be outside what we dictate to be allowed */ if ((val & ~limit_mask) != 0) { return (false); } return (true); }