[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [xen stable-4.17] x86/boot: Merge CPUID policy initialisation logic into cpu-policy.c
commit dd5f878145160c0b249c856a5f41f2d9d5e8f9d9 Author: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> AuthorDate: Mon Apr 3 19:06:02 2023 +0100 Commit: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> CommitDate: Tue Aug 8 16:02:17 2023 +0100 x86/boot: Merge CPUID policy initialisation logic into cpu-policy.c Switch to the newer cpu_policy nomenclature. Do some easy cleanup of includes. No practical change. Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> Acked-by: Jan Beulich <jbeulich@xxxxxxxx> (cherry picked from commit 8eb56eb959a50bf9afd0fd590ec394e9145970a4) --- xen/arch/x86/cpu-policy.c | 743 +++++++++++++++++++++++++++++++ xen/arch/x86/cpuid.c | 808 +--------------------------------- xen/arch/x86/hvm/hvm.c | 1 - xen/arch/x86/include/asm/cpu-policy.h | 6 + xen/arch/x86/include/asm/cpuid.h | 11 +- xen/arch/x86/pv/domain.c | 1 + xen/arch/x86/setup.c | 2 - 7 files changed, 755 insertions(+), 817 deletions(-) diff --git a/xen/arch/x86/cpu-policy.c b/xen/arch/x86/cpu-policy.c index f6a2317ed7..9c506b6614 100644 --- a/xen/arch/x86/cpu-policy.c +++ b/xen/arch/x86/cpu-policy.c @@ -1,13 +1,19 @@ /* SPDX-License-Identifier: GPL-2.0-or-later */ #include <xen/cache.h> #include <xen/kernel.h> +#include <xen/param.h> #include <xen/sched.h> #include <xen/lib/x86/cpu-policy.h> +#include <asm/amd.h> #include <asm/cpu-policy.h> +#include <asm/hvm/nestedhvm.h> +#include <asm/hvm/svm/svm.h> #include <asm/msr-index.h> +#include <asm/paging.h> #include <asm/setup.h> +#include <asm/xstate.h> struct cpu_policy __ro_after_init raw_cpu_policy; struct cpu_policy __ro_after_init host_cpu_policy; @@ -20,10 +26,332 @@ struct cpu_policy __ro_after_init hvm_max_cpu_policy; struct cpu_policy __ro_after_init hvm_def_cpu_policy; #endif +const uint32_t known_features[] = INIT_KNOWN_FEATURES; + +static const uint32_t __initconst pv_max_featuremask[] = INIT_PV_MAX_FEATURES; +static const uint32_t hvm_shadow_max_featuremask[] = INIT_HVM_SHADOW_MAX_FEATURES; +static const uint32_t __initconst hvm_hap_max_featuremask[] = + INIT_HVM_HAP_MAX_FEATURES; +static const uint32_t __initconst pv_def_featuremask[] = INIT_PV_DEF_FEATURES; +static const uint32_t __initconst hvm_shadow_def_featuremask[] = + INIT_HVM_SHADOW_DEF_FEATURES; +static const uint32_t __initconst hvm_hap_def_featuremask[] = + INIT_HVM_HAP_DEF_FEATURES; +static const uint32_t deep_features[] = INIT_DEEP_FEATURES; + +static const struct feature_name { + const char *name; + unsigned int bit; +} feature_names[] __initconstrel = INIT_FEATURE_NAMES; + +/* + * Parse a list of cpuid feature names -> bool, calling the callback for any + * matches found. + * + * always_inline, because this is init code only and we really don't want a + * function pointer call in the middle of the loop. + */ +static int __init always_inline parse_cpuid( + const char *s, void (*callback)(unsigned int feat, bool val)) +{ + const char *ss; + int val, rc = 0; + + do { + const struct feature_name *lhs, *rhs, *mid = NULL /* GCC... */; + const char *feat; + + ss = strchr(s, ','); + if ( !ss ) + ss = strchr(s, '\0'); + + /* Skip the 'no-' prefix for name comparisons. */ + feat = s; + if ( strncmp(s, "no-", 3) == 0 ) + feat += 3; + + /* (Re)initalise lhs and rhs for binary search. */ + lhs = feature_names; + rhs = feature_names + ARRAY_SIZE(feature_names); + + while ( lhs < rhs ) + { + int res; + + mid = lhs + (rhs - lhs) / 2; + res = cmdline_strcmp(feat, mid->name); + + if ( res < 0 ) + { + rhs = mid; + continue; + } + if ( res > 0 ) + { + lhs = mid + 1; + continue; + } + + if ( (val = parse_boolean(mid->name, s, ss)) >= 0 ) + { + callback(mid->bit, val); + mid = NULL; + } + + break; + } + + /* + * Mid being NULL means that the name and boolean were successfully + * identified. Everything else is an error. + */ + if ( mid ) + rc = -EINVAL; + + s = ss + 1; + } while ( *ss ); + + return rc; +} + +static void __init cf_check _parse_xen_cpuid(unsigned int feat, bool val) +{ + if ( !val ) + setup_clear_cpu_cap(feat); + else if ( feat == X86_FEATURE_RDRAND && + (cpuid_ecx(1) & cpufeat_mask(X86_FEATURE_RDRAND)) ) + setup_force_cpu_cap(X86_FEATURE_RDRAND); +} + +static int __init cf_check parse_xen_cpuid(const char *s) +{ + return parse_cpuid(s, _parse_xen_cpuid); +} +custom_param("cpuid", parse_xen_cpuid); + +static bool __initdata dom0_cpuid_cmdline; +static uint32_t __initdata dom0_enable_feat[FSCAPINTS]; +static uint32_t __initdata dom0_disable_feat[FSCAPINTS]; + +static void __init cf_check _parse_dom0_cpuid(unsigned int feat, bool val) +{ + __set_bit (feat, val ? dom0_enable_feat : dom0_disable_feat); + __clear_bit(feat, val ? dom0_disable_feat : dom0_enable_feat ); +} + +static int __init cf_check parse_dom0_cpuid(const char *s) +{ + dom0_cpuid_cmdline = true; + + return parse_cpuid(s, _parse_dom0_cpuid); +} +custom_param("dom0-cpuid", parse_dom0_cpuid); + +#define EMPTY_LEAF ((struct cpuid_leaf){}) +static void zero_leaves(struct cpuid_leaf *l, + unsigned int first, unsigned int last) +{ + memset(&l[first], 0, sizeof(*l) * (last - first + 1)); +} + +static void sanitise_featureset(uint32_t *fs) +{ + /* for_each_set_bit() uses unsigned longs. Extend with zeroes. */ + uint32_t disabled_features[ + ROUNDUP(FSCAPINTS, sizeof(unsigned long)/sizeof(uint32_t))] = {}; + unsigned int i; + + for ( i = 0; i < FSCAPINTS; ++i ) + { + /* Clamp to known mask. */ + fs[i] &= known_features[i]; + + /* + * Identify which features with deep dependencies have been + * disabled. + */ + disabled_features[i] = ~fs[i] & deep_features[i]; + } + + for_each_set_bit(i, (void *)disabled_features, + sizeof(disabled_features) * 8) + { + const uint32_t *dfs = x86_cpuid_lookup_deep_deps(i); + unsigned int j; + + ASSERT(dfs); /* deep_features[] should guarentee this. */ + + for ( j = 0; j < FSCAPINTS; ++j ) + { + fs[j] &= ~dfs[j]; + disabled_features[j] &= ~dfs[j]; + } + } +} + +static void recalculate_xstate(struct cpu_policy *p) +{ + uint64_t xstates = XSTATE_FP_SSE; + uint32_t xstate_size = XSTATE_AREA_MIN_SIZE; + unsigned int i, Da1 = p->xstate.Da1; + + /* + * The Da1 leaf is the only piece of information preserved in the common + * case. Everything else is derived from other feature state. + */ + memset(&p->xstate, 0, sizeof(p->xstate)); + + if ( !p->basic.xsave ) + return; + + if ( p->basic.avx ) + { + xstates |= X86_XCR0_YMM; + xstate_size = max(xstate_size, + xstate_offsets[X86_XCR0_YMM_POS] + + xstate_sizes[X86_XCR0_YMM_POS]); + } + + if ( p->feat.mpx ) + { + xstates |= X86_XCR0_BNDREGS | X86_XCR0_BNDCSR; + xstate_size = max(xstate_size, + xstate_offsets[X86_XCR0_BNDCSR_POS] + + xstate_sizes[X86_XCR0_BNDCSR_POS]); + } + + if ( p->feat.avx512f ) + { + xstates |= X86_XCR0_OPMASK | X86_XCR0_ZMM | X86_XCR0_HI_ZMM; + xstate_size = max(xstate_size, + xstate_offsets[X86_XCR0_HI_ZMM_POS] + + xstate_sizes[X86_XCR0_HI_ZMM_POS]); + } + + if ( p->feat.pku ) + { + xstates |= X86_XCR0_PKRU; + xstate_size = max(xstate_size, + xstate_offsets[X86_XCR0_PKRU_POS] + + xstate_sizes[X86_XCR0_PKRU_POS]); + } + + p->xstate.max_size = xstate_size; + p->xstate.xcr0_low = xstates & ~XSTATE_XSAVES_ONLY; + p->xstate.xcr0_high = (xstates & ~XSTATE_XSAVES_ONLY) >> 32; + + p->xstate.Da1 = Da1; + if ( p->xstate.xsaves ) + { + p->xstate.xss_low = xstates & XSTATE_XSAVES_ONLY; + p->xstate.xss_high = (xstates & XSTATE_XSAVES_ONLY) >> 32; + } + else + xstates &= ~XSTATE_XSAVES_ONLY; + + for ( i = 2; i < min(63ul, ARRAY_SIZE(p->xstate.comp)); ++i ) + { + uint64_t curr_xstate = 1ul << i; + + if ( !(xstates & curr_xstate) ) + continue; + + p->xstate.comp[i].size = xstate_sizes[i]; + p->xstate.comp[i].offset = xstate_offsets[i]; + p->xstate.comp[i].xss = curr_xstate & XSTATE_XSAVES_ONLY; + p->xstate.comp[i].align = curr_xstate & xstate_align; + } +} + +/* + * Misc adjustments to the policy. Mostly clobbering reserved fields and + * duplicating shared fields. Intentionally hidden fields are annotated. + */ +static void recalculate_misc(struct cpu_policy *p) +{ + p->basic.raw_fms &= 0x0fff0fff; /* Clobber Processor Type on Intel. */ + p->basic.apic_id = 0; /* Dynamic. */ + + p->basic.raw[0x5] = EMPTY_LEAF; /* MONITOR not exposed to guests. */ + p->basic.raw[0x6] = EMPTY_LEAF; /* Therm/Power not exposed to guests. */ + + p->basic.raw[0x8] = EMPTY_LEAF; + + /* TODO: Rework topology logic. */ + memset(p->topo.raw, 0, sizeof(p->topo.raw)); + + p->basic.raw[0xc] = EMPTY_LEAF; + + p->extd.e1d &= ~CPUID_COMMON_1D_FEATURES; + + /* Most of Power/RAS hidden from guests. */ + p->extd.raw[0x7].a = p->extd.raw[0x7].b = p->extd.raw[0x7].c = 0; + + p->extd.raw[0x8].d = 0; + + switch ( p->x86_vendor ) + { + case X86_VENDOR_INTEL: + p->basic.l2_nr_queries = 1; /* Fixed to 1 query. */ + p->basic.raw[0x3] = EMPTY_LEAF; /* PSN - always hidden. */ + p->basic.raw[0x9] = EMPTY_LEAF; /* DCA - always hidden. */ + + p->extd.vendor_ebx = 0; + p->extd.vendor_ecx = 0; + p->extd.vendor_edx = 0; + + p->extd.raw[0x1].a = p->extd.raw[0x1].b = 0; + + p->extd.raw[0x5] = EMPTY_LEAF; + p->extd.raw[0x6].a = p->extd.raw[0x6].b = p->extd.raw[0x6].d = 0; + + p->extd.raw[0x8].a &= 0x0000ffff; + p->extd.raw[0x8].c = 0; + break; + + case X86_VENDOR_AMD: + case X86_VENDOR_HYGON: + zero_leaves(p->basic.raw, 0x2, 0x3); + memset(p->cache.raw, 0, sizeof(p->cache.raw)); + zero_leaves(p->basic.raw, 0x9, 0xa); + + p->extd.vendor_ebx = p->basic.vendor_ebx; + p->extd.vendor_ecx = p->basic.vendor_ecx; + p->extd.vendor_edx = p->basic.vendor_edx; + + p->extd.raw_fms = p->basic.raw_fms; + p->extd.raw[0x1].b &= 0xff00ffff; + p->extd.e1d |= p->basic._1d & CPUID_COMMON_1D_FEATURES; + + p->extd.raw[0x8].a &= 0x0000ffff; /* GuestMaxPhysAddr hidden. */ + p->extd.raw[0x8].c &= 0x0003f0ff; + + p->extd.raw[0x9] = EMPTY_LEAF; + + zero_leaves(p->extd.raw, 0xb, 0x18); + + /* 0x19 - TLB details. Pass through. */ + /* 0x1a - Perf hints. Pass through. */ + + p->extd.raw[0x1b] = EMPTY_LEAF; /* IBS - not supported. */ + p->extd.raw[0x1c] = EMPTY_LEAF; /* LWP - not supported. */ + p->extd.raw[0x1d] = EMPTY_LEAF; /* TopoExt Cache */ + p->extd.raw[0x1e] = EMPTY_LEAF; /* TopoExt APIC ID/Core/Node */ + p->extd.raw[0x1f] = EMPTY_LEAF; /* SEV */ + p->extd.raw[0x20] = EMPTY_LEAF; /* Platform QoS */ + break; + } +} + static void __init calculate_raw_policy(void) { struct cpu_policy *p = &raw_cpu_policy; + x86_cpuid_policy_fill_native(p); + + /* Nothing good will come from Xen and libx86 disagreeing on vendor. */ + ASSERT(p->x86_vendor == boot_cpu_data.x86_vendor); + /* 0x000000ce MSR_INTEL_PLATFORM_INFO */ /* Was already added by probe_cpuid_faulting() */ @@ -34,9 +362,50 @@ static void __init calculate_raw_policy(void) static void __init calculate_host_policy(void) { struct cpu_policy *p = &host_cpu_policy; + unsigned int max_extd_leaf; *p = raw_cpu_policy; + p->basic.max_leaf = + min_t(uint32_t, p->basic.max_leaf, ARRAY_SIZE(p->basic.raw) - 1); + p->feat.max_subleaf = + min_t(uint32_t, p->feat.max_subleaf, ARRAY_SIZE(p->feat.raw) - 1); + + max_extd_leaf = p->extd.max_leaf; + + /* + * For AMD/Hygon hardware before Zen3, we unilaterally modify LFENCE to be + * dispatch serialising for Spectre mitigations. Extend max_extd_leaf + * beyond what hardware supports, to include the feature leaf containing + * this information. + */ + if ( cpu_has_lfence_dispatch ) + max_extd_leaf = max(max_extd_leaf, 0x80000021); + + p->extd.max_leaf = 0x80000000 | min_t(uint32_t, max_extd_leaf & 0xffff, + ARRAY_SIZE(p->extd.raw) - 1); + + x86_cpu_featureset_to_policy(boot_cpu_data.x86_capability, p); + recalculate_xstate(p); + recalculate_misc(p); + + /* When vPMU is disabled, drop it from the host policy. */ + if ( vpmu_mode == XENPMU_MODE_OFF ) + p->basic.raw[0xa] = EMPTY_LEAF; + + if ( p->extd.svm ) + { + /* Clamp to implemented features which require hardware support. */ + p->extd.raw[0xa].d &= ((1u << SVM_FEATURE_NPT) | + (1u << SVM_FEATURE_LBRV) | + (1u << SVM_FEATURE_NRIPS) | + (1u << SVM_FEATURE_PAUSEFILTER) | + (1u << SVM_FEATURE_DECODEASSISTS)); + /* Enable features which are always emulated. */ + p->extd.raw[0xa].d |= ((1u << SVM_FEATURE_VMCBCLEAN) | + (1u << SVM_FEATURE_TSCRATEMSR)); + } + /* 0x000000ce MSR_INTEL_PLATFORM_INFO */ /* probe_cpuid_faulting() sanity checks presence of MISC_FEATURES_ENABLES */ p->platform_info.cpuid_faulting = cpu_has_cpuid_faulting; @@ -51,11 +420,88 @@ static void __init calculate_host_policy(void) ARCH_CAPS_PBRSB_NO); } +static void __init guest_common_default_feature_adjustments(uint32_t *fs) +{ + /* + * IvyBridge client parts suffer from leakage of RDRAND data due to SRBDS + * (XSA-320 / CVE-2020-0543), and won't be receiving microcode to + * compensate. + * + * Mitigate by hiding RDRAND from guests by default, unless explicitly + * overridden on the Xen command line (cpuid=rdrand). Irrespective of the + * default setting, guests can use RDRAND if explicitly enabled + * (cpuid="host,rdrand=1") in the VM's config file, and VMs which were + * previously using RDRAND can migrate in. + */ + if ( boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && + boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x3a && + cpu_has_rdrand && !is_forced_cpu_cap(X86_FEATURE_RDRAND) ) + __clear_bit(X86_FEATURE_RDRAND, fs); + + /* + * On certain hardware, speculative or errata workarounds can result in + * TSX being placed in "force-abort" mode, where it doesn't actually + * function as expected, but is technically compatible with the ISA. + * + * Do not advertise RTM to guests by default if it won't actually work. + */ + if ( rtm_disabled ) + __clear_bit(X86_FEATURE_RTM, fs); +} + +static void __init guest_common_feature_adjustments(uint32_t *fs) +{ + /* Unconditionally claim to be able to set the hypervisor bit. */ + __set_bit(X86_FEATURE_HYPERVISOR, fs); + + /* + * If IBRS is offered to the guest, unconditionally offer STIBP. It is a + * nop on non-HT hardware, and has this behaviour to make heterogeneous + * setups easier to manage. + */ + if ( test_bit(X86_FEATURE_IBRSB, fs) ) + __set_bit(X86_FEATURE_STIBP, fs); + if ( test_bit(X86_FEATURE_IBRS, fs) ) + __set_bit(X86_FEATURE_AMD_STIBP, fs); + + /* + * On hardware which supports IBRS/IBPB, we can offer IBPB independently + * of IBRS by using the AMD feature bit. An administrator may wish for + * performance reasons to offer IBPB without IBRS. + */ + if ( host_cpu_policy.feat.ibrsb ) + __set_bit(X86_FEATURE_IBPB, fs); +} + static void __init calculate_pv_max_policy(void) { struct cpu_policy *p = &pv_max_cpu_policy; + uint32_t fs[FSCAPINTS]; + unsigned int i; *p = host_cpu_policy; + x86_cpu_policy_to_featureset(p, fs); + + for ( i = 0; i < ARRAY_SIZE(fs); ++i ) + fs[i] &= pv_max_featuremask[i]; + + /* + * If Xen isn't virtualising MSR_SPEC_CTRL for PV guests (functional + * availability, or admin choice), hide the feature. + */ + if ( !boot_cpu_has(X86_FEATURE_SC_MSR_PV) ) + { + __clear_bit(X86_FEATURE_IBRSB, fs); + __clear_bit(X86_FEATURE_IBRS, fs); + } + + guest_common_feature_adjustments(fs); + + sanitise_featureset(fs); + x86_cpu_featureset_to_policy(fs, p); + recalculate_xstate(p); + + p->extd.raw[0xa] = EMPTY_LEAF; /* No SVM for PV guests. */ p->arch_caps.raw = 0; /* Not supported yet. */ } @@ -63,15 +509,103 @@ static void __init calculate_pv_max_policy(void) static void __init calculate_pv_def_policy(void) { struct cpu_policy *p = &pv_def_cpu_policy; + uint32_t fs[FSCAPINTS]; + unsigned int i; *p = pv_max_cpu_policy; + x86_cpu_policy_to_featureset(p, fs); + + for ( i = 0; i < ARRAY_SIZE(fs); ++i ) + fs[i] &= pv_def_featuremask[i]; + + guest_common_feature_adjustments(fs); + guest_common_default_feature_adjustments(fs); + + sanitise_featureset(fs); + x86_cpu_featureset_to_policy(fs, p); + recalculate_xstate(p); } static void __init calculate_hvm_max_policy(void) { struct cpu_policy *p = &hvm_max_cpu_policy; + uint32_t fs[FSCAPINTS]; + unsigned int i; + const uint32_t *mask; *p = host_cpu_policy; + x86_cpu_policy_to_featureset(p, fs); + + mask = hvm_hap_supported() ? + hvm_hap_max_featuremask : hvm_shadow_max_featuremask; + + for ( i = 0; i < ARRAY_SIZE(fs); ++i ) + fs[i] &= mask[i]; + + /* + * Xen can provide an (x2)APIC emulation to HVM guests even if the host's + * (x2)APIC isn't enabled. + */ + __set_bit(X86_FEATURE_APIC, fs); + __set_bit(X86_FEATURE_X2APIC, fs); + + /* + * We don't support EFER.LMSLE at all. AMD has dropped the feature from + * hardware and allocated a CPUID bit to indicate its absence. + */ + __set_bit(X86_FEATURE_NO_LMSL, fs); + + /* + * On AMD, PV guests are entirely unable to use SYSENTER as Xen runs in + * long mode (and init_amd() has cleared it out of host capabilities), but + * HVM guests are able if running in protected mode. + */ + if ( (boot_cpu_data.x86_vendor & (X86_VENDOR_AMD | X86_VENDOR_HYGON)) && + raw_cpu_policy.basic.sep ) + __set_bit(X86_FEATURE_SEP, fs); + + /* + * VIRT_SSBD is exposed in the default policy as a result of + * amd_virt_spec_ctrl being set, it also needs exposing in the max policy. + */ + if ( amd_virt_spec_ctrl ) + __set_bit(X86_FEATURE_VIRT_SSBD, fs); + + /* + * If Xen isn't virtualising MSR_SPEC_CTRL for HVM guests (functional + * availability, or admin choice), hide the feature. + */ + if ( !boot_cpu_has(X86_FEATURE_SC_MSR_HVM) ) + { + __clear_bit(X86_FEATURE_IBRSB, fs); + __clear_bit(X86_FEATURE_IBRS, fs); + } + else if ( boot_cpu_has(X86_FEATURE_AMD_SSBD) ) + /* + * If SPEC_CTRL.SSBD is available VIRT_SPEC_CTRL.SSBD can be exposed + * and implemented using the former. Expose in the max policy only as + * the preference is for guests to use SPEC_CTRL.SSBD if available. + */ + __set_bit(X86_FEATURE_VIRT_SSBD, fs); + + /* + * With VT-x, some features are only supported by Xen if dedicated + * hardware support is also available. + */ + if ( cpu_has_vmx ) + { + if ( !cpu_has_vmx_mpx ) + __clear_bit(X86_FEATURE_MPX, fs); + + if ( !cpu_has_vmx_xsaves ) + __clear_bit(X86_FEATURE_XSAVES, fs); + } + + guest_common_feature_adjustments(fs); + + sanitise_featureset(fs); + x86_cpu_featureset_to_policy(fs, p); + recalculate_xstate(p); /* It's always possible to emulate CPUID faulting for HVM guests */ p->platform_info.cpuid_faulting = true; @@ -82,8 +616,32 @@ static void __init calculate_hvm_max_policy(void) static void __init calculate_hvm_def_policy(void) { struct cpu_policy *p = &hvm_def_cpu_policy; + uint32_t fs[FSCAPINTS]; + unsigned int i; + const uint32_t *mask; *p = hvm_max_cpu_policy; + x86_cpu_policy_to_featureset(p, fs); + + mask = hvm_hap_supported() ? + hvm_hap_def_featuremask : hvm_shadow_def_featuremask; + + for ( i = 0; i < ARRAY_SIZE(fs); ++i ) + fs[i] &= mask[i]; + + guest_common_feature_adjustments(fs); + guest_common_default_feature_adjustments(fs); + + /* + * Only expose VIRT_SSBD if AMD_SSBD is not available, and thus + * amd_virt_spec_ctrl is set. + */ + if ( amd_virt_spec_ctrl ) + __set_bit(X86_FEATURE_VIRT_SSBD, fs); + + sanitise_featureset(fs); + x86_cpu_featureset_to_policy(fs, p); + recalculate_xstate(p); } void __init init_guest_cpu_policies(void) @@ -149,3 +707,188 @@ int init_domain_cpu_policy(struct domain *d) return 0; } + +void recalculate_cpuid_policy(struct domain *d) +{ + struct cpu_policy *p = d->arch.cpuid; + const struct cpu_policy *max = is_pv_domain(d) + ? (IS_ENABLED(CONFIG_PV) ? &pv_max_cpu_policy : NULL) + : (IS_ENABLED(CONFIG_HVM) ? &hvm_max_cpu_policy : NULL); + uint32_t fs[FSCAPINTS], max_fs[FSCAPINTS]; + unsigned int i; + + if ( !max ) + { + ASSERT_UNREACHABLE(); + return; + } + + p->x86_vendor = x86_cpuid_lookup_vendor( + p->basic.vendor_ebx, p->basic.vendor_ecx, p->basic.vendor_edx); + + p->basic.max_leaf = min(p->basic.max_leaf, max->basic.max_leaf); + p->feat.max_subleaf = min(p->feat.max_subleaf, max->feat.max_subleaf); + p->extd.max_leaf = 0x80000000 | min(p->extd.max_leaf & 0xffff, + ((p->x86_vendor & (X86_VENDOR_AMD | + X86_VENDOR_HYGON)) + ? CPUID_GUEST_NR_EXTD_AMD + : CPUID_GUEST_NR_EXTD_INTEL) - 1); + + x86_cpu_policy_to_featureset(p, fs); + x86_cpu_policy_to_featureset(max, max_fs); + + if ( is_hvm_domain(d) ) + { + /* + * HVM domains using Shadow paging have further restrictions on their + * available paging features. + */ + if ( !hap_enabled(d) ) + { + for ( i = 0; i < ARRAY_SIZE(max_fs); i++ ) + max_fs[i] &= hvm_shadow_max_featuremask[i]; + } + + /* Hide nested-virt if it hasn't been explicitly configured. */ + if ( !nestedhvm_enabled(d) ) + { + __clear_bit(X86_FEATURE_VMX, max_fs); + __clear_bit(X86_FEATURE_SVM, max_fs); + } + } + + /* + * Allow the toolstack to set HTT, X2APIC and CMP_LEGACY. These bits + * affect how to interpret topology information in other cpuid leaves. + */ + __set_bit(X86_FEATURE_HTT, max_fs); + __set_bit(X86_FEATURE_X2APIC, max_fs); + __set_bit(X86_FEATURE_CMP_LEGACY, max_fs); + + /* + * 32bit PV domains can't use any Long Mode features, and cannot use + * SYSCALL on non-AMD hardware. + */ + if ( is_pv_32bit_domain(d) ) + { + __clear_bit(X86_FEATURE_LM, max_fs); + if ( !(boot_cpu_data.x86_vendor & (X86_VENDOR_AMD | X86_VENDOR_HYGON)) ) + __clear_bit(X86_FEATURE_SYSCALL, max_fs); + } + + /* Clamp the toolstacks choices to reality. */ + for ( i = 0; i < ARRAY_SIZE(fs); i++ ) + fs[i] &= max_fs[i]; + + if ( p->basic.max_leaf < XSTATE_CPUID ) + __clear_bit(X86_FEATURE_XSAVE, fs); + + sanitise_featureset(fs); + + /* Fold host's FDP_EXCP_ONLY and NO_FPU_SEL into guest's view. */ + fs[FEATURESET_7b0] &= ~(cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | + cpufeat_mask(X86_FEATURE_NO_FPU_SEL)); + fs[FEATURESET_7b0] |= (host_cpu_policy.feat._7b0 & + (cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | + cpufeat_mask(X86_FEATURE_NO_FPU_SEL))); + + x86_cpu_featureset_to_policy(fs, p); + + /* Pass host cacheline size through to guests. */ + p->basic.clflush_size = max->basic.clflush_size; + + p->extd.maxphysaddr = min(p->extd.maxphysaddr, max->extd.maxphysaddr); + p->extd.maxphysaddr = min_t(uint8_t, p->extd.maxphysaddr, + paging_max_paddr_bits(d)); + p->extd.maxphysaddr = max_t(uint8_t, p->extd.maxphysaddr, + (p->basic.pae || p->basic.pse36) ? 36 : 32); + + p->extd.maxlinaddr = p->extd.lm ? 48 : 32; + + recalculate_xstate(p); + recalculate_misc(p); + + for ( i = 0; i < ARRAY_SIZE(p->cache.raw); ++i ) + { + if ( p->cache.subleaf[i].type >= 1 && + p->cache.subleaf[i].type <= 3 ) + { + /* Subleaf has a valid cache type. Zero reserved fields. */ + p->cache.raw[i].a &= 0xffffc3ffu; + p->cache.raw[i].d &= 0x00000007u; + } + else + { + /* Subleaf is not valid. Zero the rest of the union. */ + zero_leaves(p->cache.raw, i, ARRAY_SIZE(p->cache.raw) - 1); + break; + } + } + + if ( vpmu_mode == XENPMU_MODE_OFF || + ((vpmu_mode & XENPMU_MODE_ALL) && !is_hardware_domain(d)) ) + p->basic.raw[0xa] = EMPTY_LEAF; + + if ( !p->extd.svm ) + p->extd.raw[0xa] = EMPTY_LEAF; + + if ( !p->extd.page1gb ) + p->extd.raw[0x19] = EMPTY_LEAF; +} + +void __init init_dom0_cpuid_policy(struct domain *d) +{ + struct cpu_policy *p = d->arch.cpuid; + + /* dom0 can't migrate. Give it ITSC if available. */ + if ( cpu_has_itsc ) + p->extd.itsc = true; + + /* + * Expose the "hardware speculation behaviour" bits of ARCH_CAPS to dom0, + * so dom0 can turn off workarounds as appropriate. Temporary, until the + * domain policy logic gains a better understanding of MSRs. + */ + if ( cpu_has_arch_caps ) + p->feat.arch_caps = true; + + /* Apply dom0-cpuid= command line settings, if provided. */ + if ( dom0_cpuid_cmdline ) + { + uint32_t fs[FSCAPINTS]; + unsigned int i; + + x86_cpu_policy_to_featureset(p, fs); + + for ( i = 0; i < ARRAY_SIZE(fs); ++i ) + { + fs[i] |= dom0_enable_feat [i]; + fs[i] &= ~dom0_disable_feat[i]; + } + + x86_cpu_featureset_to_policy(fs, p); + + recalculate_cpuid_policy(d); + } +} + +static void __init __maybe_unused build_assertions(void) +{ + BUILD_BUG_ON(ARRAY_SIZE(known_features) != FSCAPINTS); + BUILD_BUG_ON(ARRAY_SIZE(pv_max_featuremask) != FSCAPINTS); + BUILD_BUG_ON(ARRAY_SIZE(hvm_shadow_max_featuremask) != FSCAPINTS); + BUILD_BUG_ON(ARRAY_SIZE(hvm_hap_max_featuremask) != FSCAPINTS); + BUILD_BUG_ON(ARRAY_SIZE(deep_features) != FSCAPINTS); + + /* Find some more clever allocation scheme if this trips. */ + BUILD_BUG_ON(sizeof(struct cpu_policy) > PAGE_SIZE); + + BUILD_BUG_ON(sizeof(raw_cpu_policy.basic) != + sizeof(raw_cpu_policy.basic.raw)); + BUILD_BUG_ON(sizeof(raw_cpu_policy.feat) != + sizeof(raw_cpu_policy.feat.raw)); + BUILD_BUG_ON(sizeof(raw_cpu_policy.xstate) != + sizeof(raw_cpu_policy.xstate.raw)); + BUILD_BUG_ON(sizeof(raw_cpu_policy.extd) != + sizeof(raw_cpu_policy.extd.raw)); +} diff --git a/xen/arch/x86/cpuid.c b/xen/arch/x86/cpuid.c index ef96af738a..3f20c342fd 100644 --- a/xen/arch/x86/cpuid.c +++ b/xen/arch/x86/cpuid.c @@ -1,629 +1,14 @@ -#include <xen/init.h> -#include <xen/lib.h> -#include <xen/param.h> #include <xen/sched.h> -#include <xen/nospec.h> -#include <asm/amd.h> +#include <xen/types.h> + +#include <public/hvm/params.h> + #include <asm/cpu-policy.h> #include <asm/cpuid.h> -#include <asm/hvm/hvm.h> -#include <asm/hvm/nestedhvm.h> -#include <asm/hvm/svm/svm.h> #include <asm/hvm/viridian.h> -#include <asm/hvm/vmx/vmcs.h> -#include <asm/paging.h> -#include <asm/processor.h> #include <asm/xstate.h> -const uint32_t known_features[] = INIT_KNOWN_FEATURES; - -static const uint32_t __initconst pv_max_featuremask[] = INIT_PV_MAX_FEATURES; -static const uint32_t hvm_shadow_max_featuremask[] = INIT_HVM_SHADOW_MAX_FEATURES; -static const uint32_t __initconst hvm_hap_max_featuremask[] = - INIT_HVM_HAP_MAX_FEATURES; -static const uint32_t __initconst pv_def_featuremask[] = INIT_PV_DEF_FEATURES; -static const uint32_t __initconst hvm_shadow_def_featuremask[] = - INIT_HVM_SHADOW_DEF_FEATURES; -static const uint32_t __initconst hvm_hap_def_featuremask[] = - INIT_HVM_HAP_DEF_FEATURES; -static const uint32_t deep_features[] = INIT_DEEP_FEATURES; - -static const struct feature_name { - const char *name; - unsigned int bit; -} feature_names[] __initconstrel = INIT_FEATURE_NAMES; - -/* - * Parse a list of cpuid feature names -> bool, calling the callback for any - * matches found. - * - * always_inline, because this is init code only and we really don't want a - * function pointer call in the middle of the loop. - */ -static int __init always_inline parse_cpuid( - const char *s, void (*callback)(unsigned int feat, bool val)) -{ - const char *ss; - int val, rc = 0; - - do { - const struct feature_name *lhs, *rhs, *mid = NULL /* GCC... */; - const char *feat; - - ss = strchr(s, ','); - if ( !ss ) - ss = strchr(s, '\0'); - - /* Skip the 'no-' prefix for name comparisons. */ - feat = s; - if ( strncmp(s, "no-", 3) == 0 ) - feat += 3; - - /* (Re)initalise lhs and rhs for binary search. */ - lhs = feature_names; - rhs = feature_names + ARRAY_SIZE(feature_names); - - while ( lhs < rhs ) - { - int res; - - mid = lhs + (rhs - lhs) / 2; - res = cmdline_strcmp(feat, mid->name); - - if ( res < 0 ) - { - rhs = mid; - continue; - } - if ( res > 0 ) - { - lhs = mid + 1; - continue; - } - - if ( (val = parse_boolean(mid->name, s, ss)) >= 0 ) - { - callback(mid->bit, val); - mid = NULL; - } - - break; - } - - /* - * Mid being NULL means that the name and boolean were successfully - * identified. Everything else is an error. - */ - if ( mid ) - rc = -EINVAL; - - s = ss + 1; - } while ( *ss ); - - return rc; -} - -static void __init cf_check _parse_xen_cpuid(unsigned int feat, bool val) -{ - if ( !val ) - setup_clear_cpu_cap(feat); - else if ( feat == X86_FEATURE_RDRAND && - (cpuid_ecx(1) & cpufeat_mask(X86_FEATURE_RDRAND)) ) - setup_force_cpu_cap(X86_FEATURE_RDRAND); -} - -static int __init cf_check parse_xen_cpuid(const char *s) -{ - return parse_cpuid(s, _parse_xen_cpuid); -} -custom_param("cpuid", parse_xen_cpuid); - -static bool __initdata dom0_cpuid_cmdline; -static uint32_t __initdata dom0_enable_feat[FSCAPINTS]; -static uint32_t __initdata dom0_disable_feat[FSCAPINTS]; - -static void __init cf_check _parse_dom0_cpuid(unsigned int feat, bool val) -{ - __set_bit (feat, val ? dom0_enable_feat : dom0_disable_feat); - __clear_bit(feat, val ? dom0_disable_feat : dom0_enable_feat ); -} - -static int __init cf_check parse_dom0_cpuid(const char *s) -{ - dom0_cpuid_cmdline = true; - - return parse_cpuid(s, _parse_dom0_cpuid); -} -custom_param("dom0-cpuid", parse_dom0_cpuid); - #define EMPTY_LEAF ((struct cpuid_leaf){}) -static void zero_leaves(struct cpuid_leaf *l, - unsigned int first, unsigned int last) -{ - memset(&l[first], 0, sizeof(*l) * (last - first + 1)); -} - -static void sanitise_featureset(uint32_t *fs) -{ - /* for_each_set_bit() uses unsigned longs. Extend with zeroes. */ - uint32_t disabled_features[ - ROUNDUP(FSCAPINTS, sizeof(unsigned long)/sizeof(uint32_t))] = {}; - unsigned int i; - - for ( i = 0; i < FSCAPINTS; ++i ) - { - /* Clamp to known mask. */ - fs[i] &= known_features[i]; - - /* - * Identify which features with deep dependencies have been - * disabled. - */ - disabled_features[i] = ~fs[i] & deep_features[i]; - } - - for_each_set_bit(i, (void *)disabled_features, - sizeof(disabled_features) * 8) - { - const uint32_t *dfs = x86_cpuid_lookup_deep_deps(i); - unsigned int j; - - ASSERT(dfs); /* deep_features[] should guarentee this. */ - - for ( j = 0; j < FSCAPINTS; ++j ) - { - fs[j] &= ~dfs[j]; - disabled_features[j] &= ~dfs[j]; - } - } -} - -static void recalculate_xstate(struct cpuid_policy *p) -{ - uint64_t xstates = XSTATE_FP_SSE; - uint32_t xstate_size = XSTATE_AREA_MIN_SIZE; - unsigned int i, Da1 = p->xstate.Da1; - - /* - * The Da1 leaf is the only piece of information preserved in the common - * case. Everything else is derived from other feature state. - */ - memset(&p->xstate, 0, sizeof(p->xstate)); - - if ( !p->basic.xsave ) - return; - - if ( p->basic.avx ) - { - xstates |= X86_XCR0_YMM; - xstate_size = max(xstate_size, - xstate_offsets[X86_XCR0_YMM_POS] + - xstate_sizes[X86_XCR0_YMM_POS]); - } - - if ( p->feat.mpx ) - { - xstates |= X86_XCR0_BNDREGS | X86_XCR0_BNDCSR; - xstate_size = max(xstate_size, - xstate_offsets[X86_XCR0_BNDCSR_POS] + - xstate_sizes[X86_XCR0_BNDCSR_POS]); - } - - if ( p->feat.avx512f ) - { - xstates |= X86_XCR0_OPMASK | X86_XCR0_ZMM | X86_XCR0_HI_ZMM; - xstate_size = max(xstate_size, - xstate_offsets[X86_XCR0_HI_ZMM_POS] + - xstate_sizes[X86_XCR0_HI_ZMM_POS]); - } - - if ( p->feat.pku ) - { - xstates |= X86_XCR0_PKRU; - xstate_size = max(xstate_size, - xstate_offsets[X86_XCR0_PKRU_POS] + - xstate_sizes[X86_XCR0_PKRU_POS]); - } - - p->xstate.max_size = xstate_size; - p->xstate.xcr0_low = xstates & ~XSTATE_XSAVES_ONLY; - p->xstate.xcr0_high = (xstates & ~XSTATE_XSAVES_ONLY) >> 32; - - p->xstate.Da1 = Da1; - if ( p->xstate.xsaves ) - { - p->xstate.xss_low = xstates & XSTATE_XSAVES_ONLY; - p->xstate.xss_high = (xstates & XSTATE_XSAVES_ONLY) >> 32; - } - else - xstates &= ~XSTATE_XSAVES_ONLY; - - for ( i = 2; i < min(63ul, ARRAY_SIZE(p->xstate.comp)); ++i ) - { - uint64_t curr_xstate = 1ul << i; - - if ( !(xstates & curr_xstate) ) - continue; - - p->xstate.comp[i].size = xstate_sizes[i]; - p->xstate.comp[i].offset = xstate_offsets[i]; - p->xstate.comp[i].xss = curr_xstate & XSTATE_XSAVES_ONLY; - p->xstate.comp[i].align = curr_xstate & xstate_align; - } -} - -/* - * Misc adjustments to the policy. Mostly clobbering reserved fields and - * duplicating shared fields. Intentionally hidden fields are annotated. - */ -static void recalculate_misc(struct cpuid_policy *p) -{ - p->basic.raw_fms &= 0x0fff0fff; /* Clobber Processor Type on Intel. */ - p->basic.apic_id = 0; /* Dynamic. */ - - p->basic.raw[0x5] = EMPTY_LEAF; /* MONITOR not exposed to guests. */ - p->basic.raw[0x6] = EMPTY_LEAF; /* Therm/Power not exposed to guests. */ - - p->basic.raw[0x8] = EMPTY_LEAF; - - /* TODO: Rework topology logic. */ - memset(p->topo.raw, 0, sizeof(p->topo.raw)); - - p->basic.raw[0xc] = EMPTY_LEAF; - - p->extd.e1d &= ~CPUID_COMMON_1D_FEATURES; - - /* Most of Power/RAS hidden from guests. */ - p->extd.raw[0x7].a = p->extd.raw[0x7].b = p->extd.raw[0x7].c = 0; - - p->extd.raw[0x8].d = 0; - - switch ( p->x86_vendor ) - { - case X86_VENDOR_INTEL: - p->basic.l2_nr_queries = 1; /* Fixed to 1 query. */ - p->basic.raw[0x3] = EMPTY_LEAF; /* PSN - always hidden. */ - p->basic.raw[0x9] = EMPTY_LEAF; /* DCA - always hidden. */ - - p->extd.vendor_ebx = 0; - p->extd.vendor_ecx = 0; - p->extd.vendor_edx = 0; - - p->extd.raw[0x1].a = p->extd.raw[0x1].b = 0; - - p->extd.raw[0x5] = EMPTY_LEAF; - p->extd.raw[0x6].a = p->extd.raw[0x6].b = p->extd.raw[0x6].d = 0; - - p->extd.raw[0x8].a &= 0x0000ffff; - p->extd.raw[0x8].c = 0; - break; - - case X86_VENDOR_AMD: - case X86_VENDOR_HYGON: - zero_leaves(p->basic.raw, 0x2, 0x3); - memset(p->cache.raw, 0, sizeof(p->cache.raw)); - zero_leaves(p->basic.raw, 0x9, 0xa); - - p->extd.vendor_ebx = p->basic.vendor_ebx; - p->extd.vendor_ecx = p->basic.vendor_ecx; - p->extd.vendor_edx = p->basic.vendor_edx; - - p->extd.raw_fms = p->basic.raw_fms; - p->extd.raw[0x1].b &= 0xff00ffff; - p->extd.e1d |= p->basic._1d & CPUID_COMMON_1D_FEATURES; - - p->extd.raw[0x8].a &= 0x0000ffff; /* GuestMaxPhysAddr hidden. */ - p->extd.raw[0x8].c &= 0x0003f0ff; - - p->extd.raw[0x9] = EMPTY_LEAF; - - zero_leaves(p->extd.raw, 0xb, 0x18); - - /* 0x19 - TLB details. Pass through. */ - /* 0x1a - Perf hints. Pass through. */ - - p->extd.raw[0x1b] = EMPTY_LEAF; /* IBS - not supported. */ - p->extd.raw[0x1c] = EMPTY_LEAF; /* LWP - not supported. */ - p->extd.raw[0x1d] = EMPTY_LEAF; /* TopoExt Cache */ - p->extd.raw[0x1e] = EMPTY_LEAF; /* TopoExt APIC ID/Core/Node */ - p->extd.raw[0x1f] = EMPTY_LEAF; /* SEV */ - p->extd.raw[0x20] = EMPTY_LEAF; /* Platform QoS */ - break; - } -} - -static void __init calculate_raw_policy(void) -{ - struct cpuid_policy *p = &raw_cpu_policy; - - x86_cpuid_policy_fill_native(p); - - /* Nothing good will come from Xen and libx86 disagreeing on vendor. */ - ASSERT(p->x86_vendor == boot_cpu_data.x86_vendor); -} - -static void __init calculate_host_policy(void) -{ - struct cpuid_policy *p = &host_cpu_policy; - unsigned int max_extd_leaf; - - *p = raw_cpu_policy; - - p->basic.max_leaf = - min_t(uint32_t, p->basic.max_leaf, ARRAY_SIZE(p->basic.raw) - 1); - p->feat.max_subleaf = - min_t(uint32_t, p->feat.max_subleaf, ARRAY_SIZE(p->feat.raw) - 1); - - max_extd_leaf = p->extd.max_leaf; - - /* - * For AMD/Hygon hardware before Zen3, we unilaterally modify LFENCE to be - * dispatch serialising for Spectre mitigations. Extend max_extd_leaf - * beyond what hardware supports, to include the feature leaf containing - * this information. - */ - if ( cpu_has_lfence_dispatch ) - max_extd_leaf = max(max_extd_leaf, 0x80000021); - - p->extd.max_leaf = 0x80000000 | min_t(uint32_t, max_extd_leaf & 0xffff, - ARRAY_SIZE(p->extd.raw) - 1); - - x86_cpu_featureset_to_policy(boot_cpu_data.x86_capability, p); - recalculate_xstate(p); - recalculate_misc(p); - - /* When vPMU is disabled, drop it from the host policy. */ - if ( vpmu_mode == XENPMU_MODE_OFF ) - p->basic.raw[0xa] = EMPTY_LEAF; - - if ( p->extd.svm ) - { - /* Clamp to implemented features which require hardware support. */ - p->extd.raw[0xa].d &= ((1u << SVM_FEATURE_NPT) | - (1u << SVM_FEATURE_LBRV) | - (1u << SVM_FEATURE_NRIPS) | - (1u << SVM_FEATURE_PAUSEFILTER) | - (1u << SVM_FEATURE_DECODEASSISTS)); - /* Enable features which are always emulated. */ - p->extd.raw[0xa].d |= ((1u << SVM_FEATURE_VMCBCLEAN) | - (1u << SVM_FEATURE_TSCRATEMSR)); - } -} - -static void __init guest_common_default_feature_adjustments(uint32_t *fs) -{ - /* - * IvyBridge client parts suffer from leakage of RDRAND data due to SRBDS - * (XSA-320 / CVE-2020-0543), and won't be receiving microcode to - * compensate. - * - * Mitigate by hiding RDRAND from guests by default, unless explicitly - * overridden on the Xen command line (cpuid=rdrand). Irrespective of the - * default setting, guests can use RDRAND if explicitly enabled - * (cpuid="host,rdrand=1") in the VM's config file, and VMs which were - * previously using RDRAND can migrate in. - */ - if ( boot_cpu_data.x86_vendor == X86_VENDOR_INTEL && - boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model == 0x3a && - cpu_has_rdrand && !is_forced_cpu_cap(X86_FEATURE_RDRAND) ) - __clear_bit(X86_FEATURE_RDRAND, fs); - - /* - * On certain hardware, speculative or errata workarounds can result in - * TSX being placed in "force-abort" mode, where it doesn't actually - * function as expected, but is technically compatible with the ISA. - * - * Do not advertise RTM to guests by default if it won't actually work. - */ - if ( rtm_disabled ) - __clear_bit(X86_FEATURE_RTM, fs); -} - -static void __init guest_common_feature_adjustments(uint32_t *fs) -{ - /* Unconditionally claim to be able to set the hypervisor bit. */ - __set_bit(X86_FEATURE_HYPERVISOR, fs); - - /* - * If IBRS is offered to the guest, unconditionally offer STIBP. It is a - * nop on non-HT hardware, and has this behaviour to make heterogeneous - * setups easier to manage. - */ - if ( test_bit(X86_FEATURE_IBRSB, fs) ) - __set_bit(X86_FEATURE_STIBP, fs); - if ( test_bit(X86_FEATURE_IBRS, fs) ) - __set_bit(X86_FEATURE_AMD_STIBP, fs); - - /* - * On hardware which supports IBRS/IBPB, we can offer IBPB independently - * of IBRS by using the AMD feature bit. An administrator may wish for - * performance reasons to offer IBPB without IBRS. - */ - if ( host_cpu_policy.feat.ibrsb ) - __set_bit(X86_FEATURE_IBPB, fs); -} - -static void __init calculate_pv_max_policy(void) -{ - struct cpuid_policy *p = &pv_max_cpu_policy; - uint32_t pv_featureset[FSCAPINTS]; - unsigned int i; - - *p = host_cpu_policy; - x86_cpu_policy_to_featureset(p, pv_featureset); - - for ( i = 0; i < ARRAY_SIZE(pv_featureset); ++i ) - pv_featureset[i] &= pv_max_featuremask[i]; - - /* - * If Xen isn't virtualising MSR_SPEC_CTRL for PV guests (functional - * availability, or admin choice), hide the feature. - */ - if ( !boot_cpu_has(X86_FEATURE_SC_MSR_PV) ) - { - __clear_bit(X86_FEATURE_IBRSB, pv_featureset); - __clear_bit(X86_FEATURE_IBRS, pv_featureset); - } - - guest_common_feature_adjustments(pv_featureset); - - sanitise_featureset(pv_featureset); - x86_cpu_featureset_to_policy(pv_featureset, p); - recalculate_xstate(p); - - p->extd.raw[0xa] = EMPTY_LEAF; /* No SVM for PV guests. */ -} - -static void __init calculate_pv_def_policy(void) -{ - struct cpuid_policy *p = &pv_def_cpu_policy; - uint32_t pv_featureset[FSCAPINTS]; - unsigned int i; - - *p = pv_max_cpu_policy; - x86_cpu_policy_to_featureset(p, pv_featureset); - - for ( i = 0; i < ARRAY_SIZE(pv_featureset); ++i ) - pv_featureset[i] &= pv_def_featuremask[i]; - - guest_common_feature_adjustments(pv_featureset); - guest_common_default_feature_adjustments(pv_featureset); - - sanitise_featureset(pv_featureset); - x86_cpu_featureset_to_policy(pv_featureset, p); - recalculate_xstate(p); -} - -static void __init calculate_hvm_max_policy(void) -{ - struct cpuid_policy *p = &hvm_max_cpu_policy; - uint32_t hvm_featureset[FSCAPINTS]; - unsigned int i; - const uint32_t *hvm_featuremask; - - *p = host_cpu_policy; - x86_cpu_policy_to_featureset(p, hvm_featureset); - - hvm_featuremask = hvm_hap_supported() ? - hvm_hap_max_featuremask : hvm_shadow_max_featuremask; - - for ( i = 0; i < ARRAY_SIZE(hvm_featureset); ++i ) - hvm_featureset[i] &= hvm_featuremask[i]; - - /* - * Xen can provide an (x2)APIC emulation to HVM guests even if the host's - * (x2)APIC isn't enabled. - */ - __set_bit(X86_FEATURE_APIC, hvm_featureset); - __set_bit(X86_FEATURE_X2APIC, hvm_featureset); - - /* - * We don't support EFER.LMSLE at all. AMD has dropped the feature from - * hardware and allocated a CPUID bit to indicate its absence. - */ - __set_bit(X86_FEATURE_NO_LMSL, hvm_featureset); - - /* - * On AMD, PV guests are entirely unable to use SYSENTER as Xen runs in - * long mode (and init_amd() has cleared it out of host capabilities), but - * HVM guests are able if running in protected mode. - */ - if ( (boot_cpu_data.x86_vendor & (X86_VENDOR_AMD | X86_VENDOR_HYGON)) && - raw_cpu_policy.basic.sep ) - __set_bit(X86_FEATURE_SEP, hvm_featureset); - - /* - * VIRT_SSBD is exposed in the default policy as a result of - * amd_virt_spec_ctrl being set, it also needs exposing in the max policy. - */ - if ( amd_virt_spec_ctrl ) - __set_bit(X86_FEATURE_VIRT_SSBD, hvm_featureset); - - /* - * If Xen isn't virtualising MSR_SPEC_CTRL for HVM guests (functional - * availability, or admin choice), hide the feature. - */ - if ( !boot_cpu_has(X86_FEATURE_SC_MSR_HVM) ) - { - __clear_bit(X86_FEATURE_IBRSB, hvm_featureset); - __clear_bit(X86_FEATURE_IBRS, hvm_featureset); - } - else if ( boot_cpu_has(X86_FEATURE_AMD_SSBD) ) - /* - * If SPEC_CTRL.SSBD is available VIRT_SPEC_CTRL.SSBD can be exposed - * and implemented using the former. Expose in the max policy only as - * the preference is for guests to use SPEC_CTRL.SSBD if available. - */ - __set_bit(X86_FEATURE_VIRT_SSBD, hvm_featureset); - - /* - * With VT-x, some features are only supported by Xen if dedicated - * hardware support is also available. - */ - if ( cpu_has_vmx ) - { - if ( !cpu_has_vmx_mpx ) - __clear_bit(X86_FEATURE_MPX, hvm_featureset); - - if ( !cpu_has_vmx_xsaves ) - __clear_bit(X86_FEATURE_XSAVES, hvm_featureset); - } - - guest_common_feature_adjustments(hvm_featureset); - - sanitise_featureset(hvm_featureset); - x86_cpu_featureset_to_policy(hvm_featureset, p); - recalculate_xstate(p); -} - -static void __init calculate_hvm_def_policy(void) -{ - struct cpuid_policy *p = &hvm_def_cpu_policy; - uint32_t hvm_featureset[FSCAPINTS]; - unsigned int i; - const uint32_t *hvm_featuremask; - - *p = hvm_max_cpu_policy; - x86_cpu_policy_to_featureset(p, hvm_featureset); - - hvm_featuremask = hvm_hap_supported() ? - hvm_hap_def_featuremask : hvm_shadow_def_featuremask; - - for ( i = 0; i < ARRAY_SIZE(hvm_featureset); ++i ) - hvm_featureset[i] &= hvm_featuremask[i]; - - guest_common_feature_adjustments(hvm_featureset); - guest_common_default_feature_adjustments(hvm_featureset); - - /* - * Only expose VIRT_SSBD if AMD_SSBD is not available, and thus - * amd_virt_spec_ctrl is set. - */ - if ( amd_virt_spec_ctrl ) - __set_bit(X86_FEATURE_VIRT_SSBD, hvm_featureset); - - sanitise_featureset(hvm_featureset); - x86_cpu_featureset_to_policy(hvm_featureset, p); - recalculate_xstate(p); -} - -void __init init_guest_cpuid(void) -{ - calculate_raw_policy(); - calculate_host_policy(); - - if ( IS_ENABLED(CONFIG_PV) ) - { - calculate_pv_max_policy(); - calculate_pv_def_policy(); - } - - if ( hvm_enabled ) - { - calculate_hvm_max_policy(); - calculate_hvm_def_policy(); - } -} bool recheck_cpu_features(unsigned int cpu) { @@ -647,170 +32,6 @@ bool recheck_cpu_features(unsigned int cpu) return okay; } -void recalculate_cpuid_policy(struct domain *d) -{ - struct cpuid_policy *p = d->arch.cpuid; - const struct cpuid_policy *max = is_pv_domain(d) - ? (IS_ENABLED(CONFIG_PV) ? &pv_max_cpu_policy : NULL) - : (IS_ENABLED(CONFIG_HVM) ? &hvm_max_cpu_policy : NULL); - uint32_t fs[FSCAPINTS], max_fs[FSCAPINTS]; - unsigned int i; - - if ( !max ) - { - ASSERT_UNREACHABLE(); - return; - } - - p->x86_vendor = x86_cpuid_lookup_vendor( - p->basic.vendor_ebx, p->basic.vendor_ecx, p->basic.vendor_edx); - - p->basic.max_leaf = min(p->basic.max_leaf, max->basic.max_leaf); - p->feat.max_subleaf = min(p->feat.max_subleaf, max->feat.max_subleaf); - p->extd.max_leaf = 0x80000000 | min(p->extd.max_leaf & 0xffff, - ((p->x86_vendor & (X86_VENDOR_AMD | - X86_VENDOR_HYGON)) - ? CPUID_GUEST_NR_EXTD_AMD - : CPUID_GUEST_NR_EXTD_INTEL) - 1); - - x86_cpu_policy_to_featureset(p, fs); - x86_cpu_policy_to_featureset(max, max_fs); - - if ( is_hvm_domain(d) ) - { - /* - * HVM domains using Shadow paging have further restrictions on their - * available paging features. - */ - if ( !hap_enabled(d) ) - { - for ( i = 0; i < ARRAY_SIZE(max_fs); i++ ) - max_fs[i] &= hvm_shadow_max_featuremask[i]; - } - - /* Hide nested-virt if it hasn't been explicitly configured. */ - if ( !nestedhvm_enabled(d) ) - { - __clear_bit(X86_FEATURE_VMX, max_fs); - __clear_bit(X86_FEATURE_SVM, max_fs); - } - } - - /* - * Allow the toolstack to set HTT, X2APIC and CMP_LEGACY. These bits - * affect how to interpret topology information in other cpuid leaves. - */ - __set_bit(X86_FEATURE_HTT, max_fs); - __set_bit(X86_FEATURE_X2APIC, max_fs); - __set_bit(X86_FEATURE_CMP_LEGACY, max_fs); - - /* - * 32bit PV domains can't use any Long Mode features, and cannot use - * SYSCALL on non-AMD hardware. - */ - if ( is_pv_32bit_domain(d) ) - { - __clear_bit(X86_FEATURE_LM, max_fs); - if ( !(boot_cpu_data.x86_vendor & (X86_VENDOR_AMD | X86_VENDOR_HYGON)) ) - __clear_bit(X86_FEATURE_SYSCALL, max_fs); - } - - /* Clamp the toolstacks choices to reality. */ - for ( i = 0; i < ARRAY_SIZE(fs); i++ ) - fs[i] &= max_fs[i]; - - if ( p->basic.max_leaf < XSTATE_CPUID ) - __clear_bit(X86_FEATURE_XSAVE, fs); - - sanitise_featureset(fs); - - /* Fold host's FDP_EXCP_ONLY and NO_FPU_SEL into guest's view. */ - fs[FEATURESET_7b0] &= ~(cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | - cpufeat_mask(X86_FEATURE_NO_FPU_SEL)); - fs[FEATURESET_7b0] |= (host_cpu_policy.feat._7b0 & - (cpufeat_mask(X86_FEATURE_FDP_EXCP_ONLY) | - cpufeat_mask(X86_FEATURE_NO_FPU_SEL))); - - x86_cpu_featureset_to_policy(fs, p); - - /* Pass host cacheline size through to guests. */ - p->basic.clflush_size = max->basic.clflush_size; - - p->extd.maxphysaddr = min(p->extd.maxphysaddr, max->extd.maxphysaddr); - p->extd.maxphysaddr = min_t(uint8_t, p->extd.maxphysaddr, - paging_max_paddr_bits(d)); - p->extd.maxphysaddr = max_t(uint8_t, p->extd.maxphysaddr, - (p->basic.pae || p->basic.pse36) ? 36 : 32); - - p->extd.maxlinaddr = p->extd.lm ? 48 : 32; - - recalculate_xstate(p); - recalculate_misc(p); - - for ( i = 0; i < ARRAY_SIZE(p->cache.raw); ++i ) - { - if ( p->cache.subleaf[i].type >= 1 && - p->cache.subleaf[i].type <= 3 ) - { - /* Subleaf has a valid cache type. Zero reserved fields. */ - p->cache.raw[i].a &= 0xffffc3ffu; - p->cache.raw[i].d &= 0x00000007u; - } - else - { - /* Subleaf is not valid. Zero the rest of the union. */ - zero_leaves(p->cache.raw, i, ARRAY_SIZE(p->cache.raw) - 1); - break; - } - } - - if ( vpmu_mode == XENPMU_MODE_OFF || - ((vpmu_mode & XENPMU_MODE_ALL) && !is_hardware_domain(d)) ) - p->basic.raw[0xa] = EMPTY_LEAF; - - if ( !p->extd.svm ) - p->extd.raw[0xa] = EMPTY_LEAF; - - if ( !p->extd.page1gb ) - p->extd.raw[0x19] = EMPTY_LEAF; -} - -void __init init_dom0_cpuid_policy(struct domain *d) -{ - struct cpuid_policy *p = d->arch.cpuid; - - /* dom0 can't migrate. Give it ITSC if available. */ - if ( cpu_has_itsc ) - p->extd.itsc = true; - - /* - * Expose the "hardware speculation behaviour" bits of ARCH_CAPS to dom0, - * so dom0 can turn off workarounds as appropriate. Temporary, until the - * domain policy logic gains a better understanding of MSRs. - */ - if ( cpu_has_arch_caps ) - p->feat.arch_caps = true; - - /* Apply dom0-cpuid= command line settings, if provided. */ - if ( dom0_cpuid_cmdline ) - { - uint32_t fs[FSCAPINTS]; - unsigned int i; - - x86_cpu_policy_to_featureset(p, fs); - - for ( i = 0; i < ARRAY_SIZE(fs); ++i ) - { - fs[i] |= dom0_enable_feat [i]; - fs[i] &= ~dom0_disable_feat[i]; - } - - x86_cpu_featureset_to_policy(fs, p); - - recalculate_cpuid_policy(d); - } -} - void guest_cpuid(const struct vcpu *v, uint32_t leaf, uint32_t subleaf, struct cpuid_leaf *res) { @@ -1181,27 +402,6 @@ void guest_cpuid(const struct vcpu *v, uint32_t leaf, } } -static void __init __maybe_unused build_assertions(void) -{ - BUILD_BUG_ON(ARRAY_SIZE(known_features) != FSCAPINTS); - BUILD_BUG_ON(ARRAY_SIZE(pv_max_featuremask) != FSCAPINTS); - BUILD_BUG_ON(ARRAY_SIZE(hvm_shadow_max_featuremask) != FSCAPINTS); - BUILD_BUG_ON(ARRAY_SIZE(hvm_hap_max_featuremask) != FSCAPINTS); - BUILD_BUG_ON(ARRAY_SIZE(deep_features) != FSCAPINTS); - - /* Find some more clever allocation scheme if this trips. */ - BUILD_BUG_ON(sizeof(struct cpuid_policy) > PAGE_SIZE); - - BUILD_BUG_ON(sizeof(raw_cpu_policy.basic) != - sizeof(raw_cpu_policy.basic.raw)); - BUILD_BUG_ON(sizeof(raw_cpu_policy.feat) != - sizeof(raw_cpu_policy.feat.raw)); - BUILD_BUG_ON(sizeof(raw_cpu_policy.xstate) != - sizeof(raw_cpu_policy.xstate.raw)); - BUILD_BUG_ON(sizeof(raw_cpu_policy.extd) != - sizeof(raw_cpu_policy.extd.raw)); -} - /* * Local variables: * mode: C diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 2f20df7874..b486c0efe0 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -77,7 +77,6 @@ #include <public/memory.h> #include <public/vm_event.h> #include <public/arch-x86/cpuid.h> -#include <asm/cpuid.h> #include <compat/hvm/hvm_op.h> diff --git a/xen/arch/x86/include/asm/cpu-policy.h b/xen/arch/x86/include/asm/cpu-policy.h index 13e2a1f86d..b361537a60 100644 --- a/xen/arch/x86/include/asm/cpu-policy.h +++ b/xen/arch/x86/include/asm/cpu-policy.h @@ -18,4 +18,10 @@ void init_guest_cpu_policies(void); /* Allocate and initialise a CPU policy suitable for the domain. */ int init_domain_cpu_policy(struct domain *d); +/* Apply dom0-specific tweaks to the CPUID policy. */ +void init_dom0_cpuid_policy(struct domain *d); + +/* Clamp the CPUID policy to reality. */ +void recalculate_cpuid_policy(struct domain *d); + #endif /* X86_CPU_POLICY_H */ diff --git a/xen/arch/x86/include/asm/cpuid.h b/xen/arch/x86/include/asm/cpuid.h index 7f81b998ce..b32ba0bbfe 100644 --- a/xen/arch/x86/include/asm/cpuid.h +++ b/xen/arch/x86/include/asm/cpuid.h @@ -8,14 +8,10 @@ #include <xen/kernel.h> #include <xen/percpu.h> -#include <xen/lib/x86/cpu-policy.h> - #include <public/sysctl.h> extern const uint32_t known_features[FSCAPINTS]; -void init_guest_cpuid(void); - /* * Expected levelling capabilities (given cpuid vendor/family information), * and levelling capabilities actually available (given MSR probing). @@ -49,13 +45,8 @@ extern struct cpuidmasks cpuidmask_defaults; /* Check that all previously present features are still available. */ bool recheck_cpu_features(unsigned int cpu); -/* Apply dom0-specific tweaks to the CPUID policy. */ -void init_dom0_cpuid_policy(struct domain *d); - -/* Clamp the CPUID policy to reality. */ -void recalculate_cpuid_policy(struct domain *d); - struct vcpu; +struct cpuid_leaf; void guest_cpuid(const struct vcpu *v, uint32_t leaf, uint32_t subleaf, struct cpuid_leaf *res); diff --git a/xen/arch/x86/pv/domain.c b/xen/arch/x86/pv/domain.c index f94f28c8e2..95492715d8 100644 --- a/xen/arch/x86/pv/domain.c +++ b/xen/arch/x86/pv/domain.c @@ -10,6 +10,7 @@ #include <xen/param.h> #include <xen/sched.h> +#include <asm/cpu-policy.h> #include <asm/cpufeature.h> #include <asm/invpcid.h> #include <asm/spec_ctrl.h> diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c index 1d62ea1ad9..0c00ea875d 100644 --- a/xen/arch/x86/setup.c +++ b/xen/arch/x86/setup.c @@ -51,7 +51,6 @@ #include <asm/alternative.h> #include <asm/mc146818rtc.h> #include <asm/cpu-policy.h> -#include <asm/cpuid.h> #include <asm/spec_ctrl.h> #include <asm/guest.h> #include <asm/microcode.h> @@ -1943,7 +1942,6 @@ void __init noreturn __start_xen(unsigned long mbi_p) if ( !tboot_protect_mem_regions() ) panic("Could not protect TXT memory regions\n"); - init_guest_cpuid(); init_guest_cpu_policies(); if ( xen_cpuidle ) -- generated by git-patchbot for /home/xen/git/xen.git#stable-4.17
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