4  * cpuid support routines
24 #include <asm/cpuid.h>
25 #include "cpuid.h"
95  * Magic value used by KVM when querying userspace-provided CPUID entries and
99  * to avoid false positives when processing guest CPUID input.
110 	 * KVM has a semi-arbitrary rule that querying the guest's CPUID model  in cpuid_entry2_find()
111 	 * with IRQs disabled is disallowed.  The CPUID model can legitimately  in cpuid_entry2_find()
117 	 * of the hotpath, e.g. by caching information during CPUID updates.  in cpuid_entry2_find()
138 		 * lookup (as opposed to emulating CPUID) for a function that's  in cpuid_entry2_find()
190 /* Check whether the supplied CPUID data is equal to what is already set for the vCPU. */
216 	struct kvm_hypervisor_cpuid cpuid = {};  in kvm_get_hypervisor_cpuid()  local
231 				cpuid.base = base;  in kvm_get_hypervisor_cpuid()
232 				cpuid.limit = entry->eax;  in kvm_get_hypervisor_cpuid()
238 	return cpuid;  in kvm_get_hypervisor_cpuid()
264 	 * save the feature bitmap to avoid cpuid lookup for every PV  in kvm_update_pv_runtime()
272  * Calculate guest's supported XCR0 taking into account guest CPUID data and
363 	 * If TDP is disabled, honor *only* guest CPUID as KVM has full control  in kvm_vcpu_after_set_cpuid()
439 	 * KVM does not correctly handle changing guest CPUID after KVM_RUN, as  in kvm_set_cpuid()
447 	 * whether the supplied CPUID data is equal to what's already set.  in kvm_set_cpuid()
473 	vcpu->arch.xen.cpuid = kvm_get_hypervisor_cpuid(vcpu, XEN_SIGNATURE);  in kvm_set_cpuid()
481 			     struct kvm_cpuid *cpuid,  in kvm_vcpu_ioctl_set_cpuid()  argument
488 	if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)  in kvm_vcpu_ioctl_set_cpuid()
491 	if (cpuid->nent) {  in kvm_vcpu_ioctl_set_cpuid()
492 		e = vmemdup_user(entries, array_size(sizeof(*e), cpuid->nent));  in kvm_vcpu_ioctl_set_cpuid()
496 		e2 = kvmalloc_array(cpuid->nent, sizeof(*e2), GFP_KERNEL_ACCOUNT);  in kvm_vcpu_ioctl_set_cpuid()
502 	for (i = 0; i < cpuid->nent; i++) {  in kvm_vcpu_ioctl_set_cpuid()
515 	r = kvm_set_cpuid(vcpu, e2, cpuid->nent);  in kvm_vcpu_ioctl_set_cpuid()
526 			      struct kvm_cpuid2 *cpuid,  in kvm_vcpu_ioctl_set_cpuid2()  argument
532 	if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)  in kvm_vcpu_ioctl_set_cpuid2()
535 	if (cpuid->nent) {  in kvm_vcpu_ioctl_set_cpuid2()
536 		e2 = vmemdup_user(entries, array_size(sizeof(*e2), cpuid->nent));  in kvm_vcpu_ioctl_set_cpuid2()
541 	r = kvm_set_cpuid(vcpu, e2, cpuid->nent);  in kvm_vcpu_ioctl_set_cpuid2()
549 			      struct kvm_cpuid2 *cpuid,  in kvm_vcpu_ioctl_get_cpuid2()  argument
552 	if (cpuid->nent < vcpu->arch.cpuid_nent)  in kvm_vcpu_ioctl_get_cpuid2()
559 	cpuid->nent = vcpu->arch.cpuid_nent;  in kvm_vcpu_ioctl_get_cpuid2()
563 /* Mask kvm_cpu_caps for @leaf with the raw CPUID capabilities of this CPU. */
566 	const struct cpuid_reg cpuid = x86_feature_cpuid(leaf * 32);  in __kvm_cpu_cap_mask()  local
571 	cpuid_count(cpuid.function, cpuid.index,  in __kvm_cpu_cap_mask()
574 	kvm_cpu_caps[leaf] &= *__cpuid_entry_get_reg(&entry, cpuid.reg);  in __kvm_cpu_cap_mask()
620 		 * advertised to guests via CPUID!  in kvm_set_cpu_caps()
795 	 * KVM's supported CPUID if the feature is reported as supported by the  in kvm_set_cpu_caps()
800 	 * the mask with the raw host CPUID, and reporting support in AMD's  in kvm_set_cpu_caps()
950 		 * CPUID(function=2, index=0) may return different results each  in __do_cpuid_func()
952 		 * number of times software should do CPUID(2, 0).  in __do_cpuid_func()
958 		 * APM states that CPUID(2) is reserved.  in __do_cpuid_func()
961 		 * a stateful CPUID.0x2 is encountered.  in __do_cpuid_func()
1200 		 * NullSegClearsBase is not reported in CPUID on Zen2; help  in __do_cpuid_func()
1201 		 * userspace by providing the CPUID leaf ourselves.  in __do_cpuid_func()
1203 		 * However, only do it if the host has CPUID leaf 0x8000001d.  in __do_cpuid_func()
1205 		 * CPUID leaf if KVM reports that it supports 0x8000001d or  in __do_cpuid_func()
1326 	/*Add support for Centaur's CPUID instruction*/  in __do_cpuid_func()
1414 int kvm_dev_ioctl_get_cpuid(struct kvm_cpuid2 *cpuid,  in kvm_dev_ioctl_get_cpuid()  argument
1427 	if (cpuid->nent < 1)  in kvm_dev_ioctl_get_cpuid()
1429 	if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)  in kvm_dev_ioctl_get_cpuid()
1430 		cpuid->nent = KVM_MAX_CPUID_ENTRIES;  in kvm_dev_ioctl_get_cpuid()
1432 	if (sanity_check_entries(entries, cpuid->nent, type))  in kvm_dev_ioctl_get_cpuid()
1435 	array.entries = kvcalloc(cpuid->nent, sizeof(struct kvm_cpuid_entry2), GFP_KERNEL);  in kvm_dev_ioctl_get_cpuid()
1439 	array.maxnent = cpuid->nent;  in kvm_dev_ioctl_get_cpuid()
1446 	cpuid->nent = array.nent;  in kvm_dev_ioctl_get_cpuid()
1474  * Intel CPUID semantics treats any query for an out-of-range leaf as if the
1475  * highest basic leaf (i.e. CPUID.0H:EAX) were requested.  AMD CPUID semantics
1485  * class exists if a guest CPUID entry for its <base> leaf exists.  For a given
1486  * class, CPUID.<base>.EAX contains the max supported leaf for the class.
1496  * CPUID sub-classes are:
1528 	 * entry for CPUID.0xb.index (see below), then the output value for EDX  in get_out_of_range_cpuid_entry()
1529 	 * needs to be pulled from CPUID.0xb.1.  in get_out_of_range_cpuid_entry()
1535 	 * the effective CPUID entry is the max basic leaf.  Note, the index of  in get_out_of_range_cpuid_entry()