Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

* pc: Add a description for the i8042 property
* kvm: support for nested FRED
* tests/unit: fix warning when compiling test-nested-aio-poll with LTO
* kvm: refactoring of VM creation
* target/i386: expose IBPB-BRTYPE and SBPB CPUID bits to the guest
* hw/char: clean up serial
* remove virtfs-proxy-helper
* target/i386/kvm: Report which action failed in kvm_arch_put/get_registers
* qom: improvements to object_resolve_path*()

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# gpg: Signature made Thu 03 Oct 2024 21:04:27 BST
# gpg:                using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg:                issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [full]
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>" [full]
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (23 commits)
  qom: update object_resolve_path*() documentation
  qom: set *ambiguous on all paths
  qom: rename object_resolve_path_type() "ambiguousp"
  target/i386/kvm: Report which action failed in kvm_arch_put/get_registers
  kvm: Allow kvm_arch_get/put_registers to accept Error**
  accel/kvm: refactor dirty ring setup
  minikconf: print error entirely on stderr
  9p: remove 'proxy' filesystem backend driver
  hw/char: Extract serial-mm
  hw/char/serial.h: Extract serial-isa.h
  hw: Remove unused inclusion of hw/char/serial.h
  target/i386: Expose IBPB-BRTYPE and SBPB CPUID bits to the guest
  kvm: refactor core virtual machine creation into its own function
  kvm/i386: replace identity_base variable with a constant
  kvm/i386: refactor kvm_arch_init and split it into smaller functions
  kvm: replace fprintf with error_report()/printf() in kvm_init()
  kvm/i386: fix return values of is_host_cpu_intel()
  kvm/i386: make kvm_filter_msr() and related definitions private to kvm module
  hw/i386/pc: Add a description for the i8042 property
  tests/unit: remove block layer code from test-nested-aio-poll
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	hw/arm/Kconfig
#	hw/arm/pxa2xx.c

11 files changed, 267 insertions, 168 deletions

diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index 849e2e2..f1f1b5b 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -2042,7 +2042,7 @@ static int kvm_arch_put_sve(CPUState *cs)
     return 0;
 }
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     uint64_t val;
     uint32_t fpr;
@@ -2226,7 +2226,7 @@ static int kvm_arch_get_sve(CPUState *cs)
     return 0;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     uint64_t val;
     unsigned int el;
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 85ef745..ff227a8 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -1221,8 +1221,8 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
-            NULL, NULL, NULL, NULL,
-            NULL, NULL, NULL, NULL,
+            NULL, NULL, NULL, "sbpb",
+            "ibpb-brtype", NULL, NULL, NULL,
         },
         .cpuid = { .eax = 0x80000021, .reg = R_EAX, },
         .tcg_features = 0,
@@ -1435,7 +1435,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             "vmx-exit-save-efer", "vmx-exit-load-efer",
                 "vmx-exit-save-preemption-timer", "vmx-exit-clear-bndcfgs",
             NULL, "vmx-exit-clear-rtit-ctl", NULL, NULL,
-            NULL, "vmx-exit-load-pkrs", NULL, NULL,
+            NULL, "vmx-exit-load-pkrs", NULL, "vmx-exit-secondary-ctls",
         },
         .msr = {
             .index = MSR_IA32_VMX_TRUE_EXIT_CTLS,
@@ -1450,7 +1450,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
             NULL, "vmx-entry-ia32e-mode", NULL, NULL,
             NULL, "vmx-entry-load-perf-global-ctrl", "vmx-entry-load-pat", "vmx-entry-load-efer",
             "vmx-entry-load-bndcfgs", NULL, "vmx-entry-load-rtit-ctl", NULL,
-            NULL, NULL, "vmx-entry-load-pkrs", NULL,
+            NULL, NULL, "vmx-entry-load-pkrs", "vmx-entry-load-fred",
             NULL, NULL, NULL, NULL,
             NULL, NULL, NULL, NULL,
         },
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 14edd57..9c39384 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -267,12 +267,6 @@ typedef enum X86Seg {
 #define CR4_FRED_MASK   0
 #endif
 
-#ifdef TARGET_X86_64
-#define CR4_FRED_MASK   (1ULL << 32)
-#else
-#define CR4_FRED_MASK   0
-#endif
-
 #define CR4_RESERVED_MASK \
 (~(target_ulong)(CR4_VME_MASK | CR4_PVI_MASK | CR4_TSD_MASK \
                 | CR4_DE_MASK | CR4_PSE_MASK | CR4_PAE_MASK \
@@ -1192,6 +1186,7 @@ uint64_t x86_cpu_get_supported_feature_word(X86CPU *cpu, FeatureWord w);
 #define VMX_VM_EXIT_PT_CONCEAL_PIP                  0x01000000
 #define VMX_VM_EXIT_CLEAR_IA32_RTIT_CTL             0x02000000
 #define VMX_VM_EXIT_LOAD_IA32_PKRS                  0x20000000
+#define VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS     0x80000000
 
 #define VMX_VM_ENTRY_LOAD_DEBUG_CONTROLS            0x00000004
 #define VMX_VM_ENTRY_IA32E_MODE                     0x00000200
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index c8056ef..e6f9490 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -81,6 +81,16 @@
     do { } while (0)
 #endif
 
+/*
+ * On older Intel CPUs, KVM uses vm86 mode to emulate 16-bit code directly.
+ * In order to use vm86 mode, an EPT identity map and a TSS  are needed.
+ * Since these must be part of guest physical memory, we need to allocate
+ * them, both by setting their start addresses in the kernel and by
+ * creating a corresponding e820 entry. We need 4 pages before the BIOS,
+ * so this value allows up to 16M BIOSes.
+ */
+#define KVM_IDENTITY_BASE 0xfeffc000
+
 /* From arch/x86/kvm/lapic.h */
 #define KVM_APIC_BUS_CYCLE_NS       1
 #define KVM_APIC_BUS_FREQUENCY      (1000000000ULL / KVM_APIC_BUS_CYCLE_NS)
@@ -92,7 +102,17 @@
  * 255 kvm_msr_entry structs */
 #define MSR_BUF_SIZE 4096
 
+typedef bool QEMURDMSRHandler(X86CPU *cpu, uint32_t msr, uint64_t *val);
+typedef bool QEMUWRMSRHandler(X86CPU *cpu, uint32_t msr, uint64_t val);
+typedef struct {
+    uint32_t msr;
+    QEMURDMSRHandler *rdmsr;
+    QEMUWRMSRHandler *wrmsr;
+} KVMMSRHandlers;
+
 static void kvm_init_msrs(X86CPU *cpu);
+static bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
+                           QEMUWRMSRHandler *wrmsr);
 
 const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
     KVM_CAP_INFO(SET_TSS_ADDR),
@@ -2896,9 +2916,9 @@ static int kvm_msr_energy_thread_init(KVMState *s, MachineState *ms)
      * 1. Host cpu must be Intel cpu
      * 2. RAPL must be enabled on the Host
      */
-    if (is_host_cpu_intel()) {
-        error_report("The RAPL feature can only be enabled on hosts\
-                      with Intel CPU models");
+    if (!is_host_cpu_intel()) {
+        error_report("The RAPL feature can only be enabled on hosts "
+                     "with Intel CPU models");
         ret = 1;
         goto out;
     }
@@ -2995,10 +3015,174 @@ int kvm_arch_get_default_type(MachineState *ms)
     return 0;
 }
 
-int kvm_arch_init(MachineState *ms, KVMState *s)
+static int kvm_vm_enable_exception_payload(KVMState *s)
+{
+    int ret = 0;
+    has_exception_payload = kvm_check_extension(s, KVM_CAP_EXCEPTION_PAYLOAD);
+    if (has_exception_payload) {
+        ret = kvm_vm_enable_cap(s, KVM_CAP_EXCEPTION_PAYLOAD, 0, true);
+        if (ret < 0) {
+            error_report("kvm: Failed to enable exception payload cap: %s",
+                         strerror(-ret));
+        }
+    }
+
+    return ret;
+}
+
+static int kvm_vm_enable_triple_fault_event(KVMState *s)
+{
+    int ret = 0;
+    has_triple_fault_event = \
+        kvm_check_extension(s,
+                            KVM_CAP_X86_TRIPLE_FAULT_EVENT);
+    if (has_triple_fault_event) {
+        ret = kvm_vm_enable_cap(s, KVM_CAP_X86_TRIPLE_FAULT_EVENT, 0, true);
+        if (ret < 0) {
+            error_report("kvm: Failed to enable triple fault event cap: %s",
+                         strerror(-ret));
+        }
+    }
+    return ret;
+}
+
+static int kvm_vm_set_identity_map_addr(KVMState *s, uint64_t identity_base)
+{
+    return kvm_vm_ioctl(s, KVM_SET_IDENTITY_MAP_ADDR, &identity_base);
+}
+
+static int kvm_vm_set_nr_mmu_pages(KVMState *s)
 {
-    uint64_t identity_base = 0xfffbc000;
     uint64_t shadow_mem;
+    int ret = 0;
+    shadow_mem = object_property_get_int(OBJECT(s),
+                                         "kvm-shadow-mem",
+                                         &error_abort);
+    if (shadow_mem != -1) {
+        shadow_mem /= 4096;
+        ret = kvm_vm_ioctl(s, KVM_SET_NR_MMU_PAGES, shadow_mem);
+    }
+    return ret;
+}
+
+static int kvm_vm_set_tss_addr(KVMState *s, uint64_t tss_base)
+{
+    return kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, tss_base);
+}
+
+static int kvm_vm_enable_disable_exits(KVMState *s)
+{
+    int disable_exits = kvm_check_extension(s, KVM_CAP_X86_DISABLE_EXITS);
+/* Work around for kernel header with a typo. TODO: fix header and drop. */
+#if defined(KVM_X86_DISABLE_EXITS_HTL) && !defined(KVM_X86_DISABLE_EXITS_HLT)
+#define KVM_X86_DISABLE_EXITS_HLT KVM_X86_DISABLE_EXITS_HTL
+#endif
+    if (disable_exits) {
+        disable_exits &= (KVM_X86_DISABLE_EXITS_MWAIT |
+                          KVM_X86_DISABLE_EXITS_HLT |
+                          KVM_X86_DISABLE_EXITS_PAUSE |
+                          KVM_X86_DISABLE_EXITS_CSTATE);
+    }
+
+    return kvm_vm_enable_cap(s, KVM_CAP_X86_DISABLE_EXITS, 0,
+                             disable_exits);
+}
+
+static int kvm_vm_enable_bus_lock_exit(KVMState *s)
+{
+    int ret = 0;
+    ret = kvm_check_extension(s, KVM_CAP_X86_BUS_LOCK_EXIT);
+    if (!(ret & KVM_BUS_LOCK_DETECTION_EXIT)) {
+        error_report("kvm: bus lock detection unsupported");
+        return -ENOTSUP;
+    }
+    ret = kvm_vm_enable_cap(s, KVM_CAP_X86_BUS_LOCK_EXIT, 0,
+                            KVM_BUS_LOCK_DETECTION_EXIT);
+    if (ret < 0) {
+        error_report("kvm: Failed to enable bus lock detection cap: %s",
+                     strerror(-ret));
+    }
+
+    return ret;
+}
+
+static int kvm_vm_enable_notify_vmexit(KVMState *s)
+{
+    int ret = 0;
+    if (s->notify_vmexit != NOTIFY_VMEXIT_OPTION_DISABLE) {
+        uint64_t notify_window_flags =
+            ((uint64_t)s->notify_window << 32) |
+            KVM_X86_NOTIFY_VMEXIT_ENABLED |
+            KVM_X86_NOTIFY_VMEXIT_USER;
+        ret = kvm_vm_enable_cap(s, KVM_CAP_X86_NOTIFY_VMEXIT, 0,
+                                notify_window_flags);
+        if (ret < 0) {
+            error_report("kvm: Failed to enable notify vmexit cap: %s",
+                         strerror(-ret));
+        }
+    }
+    return ret;
+}
+
+static int kvm_vm_enable_userspace_msr(KVMState *s)
+{
+    int ret = kvm_vm_enable_cap(s, KVM_CAP_X86_USER_SPACE_MSR, 0,
+                                KVM_MSR_EXIT_REASON_FILTER);
+    if (ret < 0) {
+        error_report("Could not enable user space MSRs: %s",
+                     strerror(-ret));
+        exit(1);
+    }
+
+    if (!kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
+                        kvm_rdmsr_core_thread_count, NULL)) {
+        error_report("Could not install MSR_CORE_THREAD_COUNT handler!");
+        exit(1);
+    }
+
+    return 0;
+}
+
+static void kvm_vm_enable_energy_msrs(KVMState *s)
+{
+    bool r;
+    if (s->msr_energy.enable == true) {
+        r = kvm_filter_msr(s, MSR_RAPL_POWER_UNIT,
+                           kvm_rdmsr_rapl_power_unit, NULL);
+        if (!r) {
+            error_report("Could not install MSR_RAPL_POWER_UNIT \
+                                handler");
+            exit(1);
+        }
+
+        r = kvm_filter_msr(s, MSR_PKG_POWER_LIMIT,
+                           kvm_rdmsr_pkg_power_limit, NULL);
+        if (!r) {
+            error_report("Could not install MSR_PKG_POWER_LIMIT \
+                                handler");
+            exit(1);
+        }
+
+        r = kvm_filter_msr(s, MSR_PKG_POWER_INFO,
+                           kvm_rdmsr_pkg_power_info, NULL);
+        if (!r) {
+            error_report("Could not install MSR_PKG_POWER_INFO \
+                                handler");
+            exit(1);
+        }
+        r = kvm_filter_msr(s, MSR_PKG_ENERGY_STATUS,
+                           kvm_rdmsr_pkg_energy_status, NULL);
+        if (!r) {
+            error_report("Could not install MSR_PKG_ENERGY_STATUS \
+                                handler");
+            exit(1);
+        }
+    }
+    return;
+}
+
+int kvm_arch_init(MachineState *ms, KVMState *s)
+{
     int ret;
     struct utsname utsname;
     Error *local_err = NULL;
@@ -3028,24 +3212,14 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
 
     hv_vpindex_settable = kvm_check_extension(s, KVM_CAP_HYPERV_VP_INDEX);
 
-    has_exception_payload = kvm_check_extension(s, KVM_CAP_EXCEPTION_PAYLOAD);
-    if (has_exception_payload) {
-        ret = kvm_vm_enable_cap(s, KVM_CAP_EXCEPTION_PAYLOAD, 0, true);
-        if (ret < 0) {
-            error_report("kvm: Failed to enable exception payload cap: %s",
-                         strerror(-ret));
-            return ret;
-        }
+    ret = kvm_vm_enable_exception_payload(s);
+    if (ret < 0) {
+        return ret;
     }
 
-    has_triple_fault_event = kvm_check_extension(s, KVM_CAP_X86_TRIPLE_FAULT_EVENT);
-    if (has_triple_fault_event) {
-        ret = kvm_vm_enable_cap(s, KVM_CAP_X86_TRIPLE_FAULT_EVENT, 0, true);
-        if (ret < 0) {
-            error_report("kvm: Failed to enable triple fault event cap: %s",
-                         strerror(-ret));
-            return ret;
-        }
+    ret = kvm_vm_enable_triple_fault_event(s);
+    if (ret < 0) {
+        return ret;
     }
 
     if (s->xen_version) {
@@ -3076,36 +3250,23 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     uname(&utsname);
     lm_capable_kernel = strcmp(utsname.machine, "x86_64") == 0;
 
-    /*
-     * On older Intel CPUs, KVM uses vm86 mode to emulate 16-bit code directly.
-     * In order to use vm86 mode, an EPT identity map and a TSS  are needed.
-     * Since these must be part of guest physical memory, we need to allocate
-     * them, both by setting their start addresses in the kernel and by
-     * creating a corresponding e820 entry. We need 4 pages before the BIOS,
-     * so this value allows up to 16M BIOSes.
-     */
-    identity_base = 0xfeffc000;
-    ret = kvm_vm_ioctl(s, KVM_SET_IDENTITY_MAP_ADDR, &identity_base);
+    ret = kvm_vm_set_identity_map_addr(s, KVM_IDENTITY_BASE);
     if (ret < 0) {
         return ret;
     }
 
     /* Set TSS base one page after EPT identity map. */
-    ret = kvm_vm_ioctl(s, KVM_SET_TSS_ADDR, identity_base + 0x1000);
+    ret = kvm_vm_set_tss_addr(s, KVM_IDENTITY_BASE + 0x1000);
     if (ret < 0) {
         return ret;
     }
 
     /* Tell fw_cfg to notify the BIOS to reserve the range. */
-    e820_add_entry(identity_base, 0x4000, E820_RESERVED);
+    e820_add_entry(KVM_IDENTITY_BASE, 0x4000, E820_RESERVED);
 
-    shadow_mem = object_property_get_int(OBJECT(s), "kvm-shadow-mem", &error_abort);
-    if (shadow_mem != -1) {
-        shadow_mem /= 4096;
-        ret = kvm_vm_ioctl(s, KVM_SET_NR_MMU_PAGES, shadow_mem);
-        if (ret < 0) {
-            return ret;
-        }
+    ret = kvm_vm_set_nr_mmu_pages(s);
+    if (ret < 0) {
+        return ret;
     }
 
     if (kvm_check_extension(s, KVM_CAP_X86_SMM) &&
@@ -3116,20 +3277,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     }
 
     if (enable_cpu_pm) {
-        int disable_exits = kvm_check_extension(s, KVM_CAP_X86_DISABLE_EXITS);
-/* Work around for kernel header with a typo. TODO: fix header and drop. */
-#if defined(KVM_X86_DISABLE_EXITS_HTL) && !defined(KVM_X86_DISABLE_EXITS_HLT)
-#define KVM_X86_DISABLE_EXITS_HLT KVM_X86_DISABLE_EXITS_HTL
-#endif
-        if (disable_exits) {
-            disable_exits &= (KVM_X86_DISABLE_EXITS_MWAIT |
-                              KVM_X86_DISABLE_EXITS_HLT |
-                              KVM_X86_DISABLE_EXITS_PAUSE |
-                              KVM_X86_DISABLE_EXITS_CSTATE);
-        }
-
-        ret = kvm_vm_enable_cap(s, KVM_CAP_X86_DISABLE_EXITS, 0,
-                                disable_exits);
+        ret = kvm_vm_enable_disable_exits(s);
         if (ret < 0) {
             error_report("kvm: guest stopping CPU not supported: %s",
                          strerror(-ret));
@@ -3140,16 +3288,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         X86MachineState *x86ms = X86_MACHINE(ms);
 
         if (x86ms->bus_lock_ratelimit > 0) {
-            ret = kvm_check_extension(s, KVM_CAP_X86_BUS_LOCK_EXIT);
-            if (!(ret & KVM_BUS_LOCK_DETECTION_EXIT)) {
-                error_report("kvm: bus lock detection unsupported");
-                return -ENOTSUP;
-            }
-            ret = kvm_vm_enable_cap(s, KVM_CAP_X86_BUS_LOCK_EXIT, 0,
-                                    KVM_BUS_LOCK_DETECTION_EXIT);
+            ret = kvm_vm_enable_bus_lock_exit(s);
             if (ret < 0) {
-                error_report("kvm: Failed to enable bus lock detection cap: %s",
-                             strerror(-ret));
                 return ret;
             }
             ratelimit_init(&bus_lock_ratelimit_ctrl);
@@ -3158,80 +3298,25 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
         }
     }
 
-    if (s->notify_vmexit != NOTIFY_VMEXIT_OPTION_DISABLE &&
-        kvm_check_extension(s, KVM_CAP_X86_NOTIFY_VMEXIT)) {
-            uint64_t notify_window_flags =
-                ((uint64_t)s->notify_window << 32) |
-                KVM_X86_NOTIFY_VMEXIT_ENABLED |
-                KVM_X86_NOTIFY_VMEXIT_USER;
-            ret = kvm_vm_enable_cap(s, KVM_CAP_X86_NOTIFY_VMEXIT, 0,
-                                    notify_window_flags);
-            if (ret < 0) {
-                error_report("kvm: Failed to enable notify vmexit cap: %s",
-                             strerror(-ret));
-                return ret;
-            }
-    }
-    if (kvm_vm_check_extension(s, KVM_CAP_X86_USER_SPACE_MSR)) {
-        bool r;
-
-        ret = kvm_vm_enable_cap(s, KVM_CAP_X86_USER_SPACE_MSR, 0,
-                                KVM_MSR_EXIT_REASON_FILTER);
-        if (ret) {
-            error_report("Could not enable user space MSRs: %s",
-                         strerror(-ret));
-            exit(1);
+    if (kvm_check_extension(s, KVM_CAP_X86_NOTIFY_VMEXIT)) {
+        ret = kvm_vm_enable_notify_vmexit(s);
+        if (ret < 0) {
+            return ret;
         }
+    }
 
-        r = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
-                           kvm_rdmsr_core_thread_count, NULL);
-        if (!r) {
-            error_report("Could not install MSR_CORE_THREAD_COUNT handler: %s",
-                         strerror(-ret));
-            exit(1);
+    if (kvm_vm_check_extension(s, KVM_CAP_X86_USER_SPACE_MSR)) {
+        ret = kvm_vm_enable_userspace_msr(s);
+        if (ret < 0) {
+            return ret;
         }
 
         if (s->msr_energy.enable == true) {
-            r = kvm_filter_msr(s, MSR_RAPL_POWER_UNIT,
-                               kvm_rdmsr_rapl_power_unit, NULL);
-            if (!r) {
-                error_report("Could not install MSR_RAPL_POWER_UNIT \
-                                handler: %s",
-                             strerror(-ret));
-                exit(1);
-            }
-
-            r = kvm_filter_msr(s, MSR_PKG_POWER_LIMIT,
-                               kvm_rdmsr_pkg_power_limit, NULL);
-            if (!r) {
-                error_report("Could not install MSR_PKG_POWER_LIMIT \
-                                handler: %s",
-                             strerror(-ret));
-                exit(1);
-            }
-
-            r = kvm_filter_msr(s, MSR_PKG_POWER_INFO,
-                               kvm_rdmsr_pkg_power_info, NULL);
-            if (!r) {
-                error_report("Could not install MSR_PKG_POWER_INFO \
-                                handler: %s",
-                             strerror(-ret));
+            kvm_vm_enable_energy_msrs(s);
+            if (kvm_msr_energy_thread_init(s, ms)) {
+                error_report("kvm : error RAPL feature requirement not met");
                 exit(1);
             }
-            r = kvm_filter_msr(s, MSR_PKG_ENERGY_STATUS,
-                               kvm_rdmsr_pkg_energy_status, NULL);
-            if (!r) {
-                error_report("Could not install MSR_PKG_ENERGY_STATUS \
-                                handler: %s",
-                             strerror(-ret));
-                exit(1);
-            }
-            r = kvm_msr_energy_thread_init(s, ms);
-            if (r) {
-                error_report("kvm : error RAPL feature requirement not meet");
-                exit(1);
-            }
-
         }
     }
 
@@ -3694,7 +3779,14 @@ static void kvm_msr_entry_add_vmx(X86CPU *cpu, FeatureWordArray f)
     kvm_msr_entry_add(cpu, MSR_IA32_VMX_CR4_FIXED0,
                       CR4_VMXE_MASK);
 
-    if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
+    if (f[FEAT_7_1_EAX] & CPUID_7_1_EAX_FRED) {
+        /* FRED injected-event data (0x2052).  */
+        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x52);
+    } else if (f[FEAT_VMX_EXIT_CTLS] &
+               VMX_VM_EXIT_ACTIVATE_SECONDARY_CONTROLS) {
+        /* Secondary VM-exit controls (0x2044).  */
+        kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x44);
+    } else if (f[FEAT_VMX_SECONDARY_CTLS] & VMX_SECONDARY_EXEC_TSC_SCALING) {
         /* TSC multiplier (0x2032).  */
         kvm_msr_entry_add(cpu, MSR_IA32_VMX_VMCS_ENUM, 0x32);
     } else {
@@ -5118,7 +5210,7 @@ static int kvm_get_nested_state(X86CPU *cpu)
     return ret;
 }
 
-int kvm_arch_put_registers(CPUState *cpu, int level)
+int kvm_arch_put_registers(CPUState *cpu, int level, Error **errp)
 {
     X86CPU *x86_cpu = X86_CPU(cpu);
     int ret;
@@ -5133,6 +5225,7 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
     if (level >= KVM_PUT_RESET_STATE) {
         ret = kvm_put_msr_feature_control(x86_cpu);
         if (ret < 0) {
+            error_setg_errno(errp, -ret, "Failed to set feature control MSR");
             return ret;
         }
     }
@@ -5140,12 +5233,14 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
     /* must be before kvm_put_nested_state so that EFER.SVME is set */
     ret = has_sregs2 ? kvm_put_sregs2(x86_cpu) : kvm_put_sregs(x86_cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set special registers");
         return ret;
     }
 
     if (level >= KVM_PUT_RESET_STATE) {
         ret = kvm_put_nested_state(x86_cpu);
         if (ret < 0) {
+            error_setg_errno(errp, -ret, "Failed to set nested state");
             return ret;
         }
     }
@@ -5163,6 +5258,7 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
     if (xen_mode == XEN_EMULATE && level == KVM_PUT_FULL_STATE) {
         ret = kvm_put_xen_state(cpu);
         if (ret < 0) {
+            error_setg_errno(errp, -ret, "Failed to set Xen state");
             return ret;
         }
     }
@@ -5170,43 +5266,51 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
 
     ret = kvm_getput_regs(x86_cpu, 1);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set general purpose registers");
         return ret;
     }
     ret = kvm_put_xsave(x86_cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set XSAVE");
         return ret;
     }
     ret = kvm_put_xcrs(x86_cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set XCRs");
         return ret;
     }
     ret = kvm_put_msrs(x86_cpu, level);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set MSRs");
         return ret;
     }
     ret = kvm_put_vcpu_events(x86_cpu, level);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set vCPU events");
         return ret;
     }
     if (level >= KVM_PUT_RESET_STATE) {
         ret = kvm_put_mp_state(x86_cpu);
         if (ret < 0) {
+            error_setg_errno(errp, -ret, "Failed to set MP state");
             return ret;
         }
     }
 
     ret = kvm_put_tscdeadline_msr(x86_cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set TSC deadline MSR");
         return ret;
     }
     ret = kvm_put_debugregs(x86_cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to set debug registers");
         return ret;
     }
     return 0;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     X86CPU *cpu = X86_CPU(cs);
     int ret;
@@ -5215,6 +5319,7 @@ int kvm_arch_get_registers(CPUState *cs)
 
     ret = kvm_get_vcpu_events(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get vCPU events");
         goto out;
     }
     /*
@@ -5223,44 +5328,54 @@ int kvm_arch_get_registers(CPUState *cs)
      */
     ret = kvm_get_mp_state(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get MP state");
         goto out;
     }
     ret = kvm_getput_regs(cpu, 0);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get general purpose registers");
         goto out;
     }
     ret = kvm_get_xsave(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get XSAVE");
         goto out;
     }
     ret = kvm_get_xcrs(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get XCRs");
         goto out;
     }
     ret = has_sregs2 ? kvm_get_sregs2(cpu) : kvm_get_sregs(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get special registers");
         goto out;
     }
     ret = kvm_get_msrs(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get MSRs");
         goto out;
     }
     ret = kvm_get_apic(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get APIC");
         goto out;
     }
     ret = kvm_get_debugregs(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get debug registers");
         goto out;
     }
     ret = kvm_get_nested_state(cpu);
     if (ret < 0) {
+        error_setg_errno(errp, -ret, "Failed to get nested state");
         goto out;
     }
 #ifdef CONFIG_XEN_EMU
     if (xen_mode == XEN_EMULATE) {
         ret = kvm_get_xen_state(cs);
         if (ret < 0) {
+            error_setg_errno(errp, -ret, "Failed to get Xen state");
             goto out;
         }
     }
@@ -5729,7 +5844,7 @@ static bool kvm_install_msr_filters(KVMState *s)
     return true;
 }
 
-bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
+static bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
                     QEMUWRMSRHandler *wrmsr)
 {
     int i;
diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h
index 34fc607..9de9c0d 100644
--- a/target/i386/kvm/kvm_i386.h
+++ b/target/i386/kvm/kvm_i386.h
@@ -66,17 +66,6 @@ uint64_t kvm_swizzle_msi_ext_dest_id(uint64_t address);
 void kvm_update_msi_routes_all(void *private, bool global,
                                uint32_t index, uint32_t mask);
 
-typedef bool QEMURDMSRHandler(X86CPU *cpu, uint32_t msr, uint64_t *val);
-typedef bool QEMUWRMSRHandler(X86CPU *cpu, uint32_t msr, uint64_t val);
-typedef struct kvm_msr_handlers {
-    uint32_t msr;
-    QEMURDMSRHandler *rdmsr;
-    QEMUWRMSRHandler *wrmsr;
-} KVMMSRHandlers;
-
-bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
-                    QEMUWRMSRHandler *wrmsr);
-
 #endif /* CONFIG_KVM */
 
 void kvm_pc_setup_irq_routing(bool pci_enabled);
diff --git a/target/i386/kvm/vmsr_energy.c b/target/i386/kvm/vmsr_energy.c
index 7e064c5..31508d4 100644
--- a/target/i386/kvm/vmsr_energy.c
+++ b/target/i386/kvm/vmsr_energy.c
@@ -34,7 +34,7 @@ bool is_host_cpu_intel(void)
 
     host_cpu_vendor_fms(vendor, &family, &model, &stepping);
 
-    return strcmp(vendor, CPUID_VENDOR_INTEL);
+    return g_str_equal(vendor, CPUID_VENDOR_INTEL);
 }
 
 int is_rapl_enabled(void)
diff --git a/target/loongarch/kvm/kvm.c b/target/loongarch/kvm/kvm.c
index 4786cd5..30ec160 100644
--- a/target/loongarch/kvm/kvm.c
+++ b/target/loongarch/kvm/kvm.c
@@ -588,7 +588,7 @@ static int kvm_loongarch_put_cpucfg(CPUState *cs)
     return ret;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     int ret;
 
@@ -616,7 +616,7 @@ int kvm_arch_get_registers(CPUState *cs)
     return ret;
 }
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     int ret;
 
diff --git a/target/mips/kvm.c b/target/mips/kvm.c
index a631ab5..a98798c 100644
--- a/target/mips/kvm.c
+++ b/target/mips/kvm.c
@@ -1172,7 +1172,7 @@ static int kvm_mips_get_cp0_registers(CPUState *cs)
     return ret;
 }
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     CPUMIPSState *env = cpu_env(cs);
     struct kvm_regs regs;
@@ -1207,7 +1207,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
     return ret;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     CPUMIPSState *env = cpu_env(cs);
     int ret = 0;
diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 907dba6..3efc28f 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -900,7 +900,7 @@ int kvmppc_put_books_sregs(PowerPCCPU *cpu)
     return kvm_vcpu_ioctl(CPU(cpu), KVM_SET_SREGS, &sregs);
 }
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     PowerPCCPU *cpu = POWERPC_CPU(cs);
     CPUPPCState *env = &cpu->env;
@@ -1205,7 +1205,7 @@ static int kvmppc_get_books_sregs(PowerPCCPU *cpu)
     return 0;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     PowerPCCPU *cpu = POWERPC_CPU(cs);
     CPUPPCState *env = &cpu->env;
diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
index 341af90..8233a32 100644
--- a/target/riscv/kvm/kvm-cpu.c
+++ b/target/riscv/kvm/kvm-cpu.c
@@ -1192,7 +1192,7 @@ const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
     KVM_CAP_LAST_INFO
 };
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     int ret = 0;
 
@@ -1237,7 +1237,7 @@ int kvm_riscv_sync_mpstate_to_kvm(RISCVCPU *cpu, int state)
     return 0;
 }
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     int ret = 0;
 
diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index 94181d9..8ffe015 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -472,7 +472,7 @@ static int can_sync_regs(CPUState *cs, int regs)
 #define KVM_SYNC_REQUIRED_REGS (KVM_SYNC_GPRS | KVM_SYNC_ACRS | \
                                 KVM_SYNC_CRS | KVM_SYNC_PREFIX)
 
-int kvm_arch_put_registers(CPUState *cs, int level)
+int kvm_arch_put_registers(CPUState *cs, int level, Error **errp)
 {
     CPUS390XState *env = cpu_env(cs);
     struct kvm_fpu fpu = {};
@@ -598,7 +598,7 @@ int kvm_arch_put_registers(CPUState *cs, int level)
     return 0;
 }
 
-int kvm_arch_get_registers(CPUState *cs)
+int kvm_arch_get_registers(CPUState *cs, Error **errp)
 {
     CPUS390XState *env = cpu_env(cs);
     struct kvm_fpu fpu;