* [PATCH 1/3] KVM: nVMX: Eliminate vmcs02 pool
2018-01-31 21:09 [PATCH v3 0/3] Per-VCPU MSR bitmaps patches - topic branch for x86/pti Paolo Bonzini
@ 2018-01-31 21:09 ` Paolo Bonzini
2018-01-31 21:09 ` [PATCH 2/3] KVM: VMX: introduce alloc_loaded_vmcs Paolo Bonzini
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Paolo Bonzini @ 2018-01-31 21:09 UTC (permalink / raw)
To: linux-kernel, kvm
Cc: Jim Mattson, Radim Krčmář, David Woodhouse,
KarimAllah Ahmed, stable, Mark Kanda
From: Jim Mattson <jmattson@google.com>
The potential performance advantages of a vmcs02 pool have never been
realized. To simplify the code, eliminate the pool. Instead, a single
vmcs02 is allocated per VCPU when the VCPU enters VMX operation.
Cc: stable@vger.kernel.org # prereq for Spectre mitigation
Signed-off-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Reviewed-by: Ameya More <ameya.more@oracle.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
---
arch/x86/kvm/vmx.c | 146 +++++++++--------------------------------------------
1 file changed, 23 insertions(+), 123 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index c829d89e2e63..ad6a883b7a32 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -185,7 +185,6 @@ module_param(ple_window_max, int, S_IRUGO);
extern const ulong vmx_return;
#define NR_AUTOLOAD_MSRS 8
-#define VMCS02_POOL_SIZE 1
struct vmcs {
u32 revision_id;
@@ -226,7 +225,7 @@ struct shared_msr_entry {
* stored in guest memory specified by VMPTRLD, but is opaque to the guest,
* which must access it using VMREAD/VMWRITE/VMCLEAR instructions.
* More than one of these structures may exist, if L1 runs multiple L2 guests.
- * nested_vmx_run() will use the data here to build a vmcs02: a VMCS for the
+ * nested_vmx_run() will use the data here to build the vmcs02: a VMCS for the
* underlying hardware which will be used to run L2.
* This structure is packed to ensure that its layout is identical across
* machines (necessary for live migration).
@@ -409,13 +408,6 @@ struct __packed vmcs12 {
*/
#define VMCS12_SIZE 0x1000
-/* Used to remember the last vmcs02 used for some recently used vmcs12s */
-struct vmcs02_list {
- struct list_head list;
- gpa_t vmptr;
- struct loaded_vmcs vmcs02;
-};
-
/*
* The nested_vmx structure is part of vcpu_vmx, and holds information we need
* for correct emulation of VMX (i.e., nested VMX) on this vcpu.
@@ -440,15 +432,15 @@ struct nested_vmx {
*/
bool sync_shadow_vmcs;
- /* vmcs02_list cache of VMCSs recently used to run L2 guests */
- struct list_head vmcs02_pool;
- int vmcs02_num;
bool change_vmcs01_virtual_x2apic_mode;
/* L2 must run next, and mustn't decide to exit to L1. */
bool nested_run_pending;
+
+ struct loaded_vmcs vmcs02;
+
/*
- * Guest pages referred to in vmcs02 with host-physical pointers, so
- * we must keep them pinned while L2 runs.
+ * Guest pages referred to in the vmcs02 with host-physical
+ * pointers, so we must keep them pinned while L2 runs.
*/
struct page *apic_access_page;
struct page *virtual_apic_page;
@@ -6973,94 +6965,6 @@ static int handle_monitor(struct kvm_vcpu *vcpu)
return handle_nop(vcpu);
}
-/*
- * To run an L2 guest, we need a vmcs02 based on the L1-specified vmcs12.
- * We could reuse a single VMCS for all the L2 guests, but we also want the
- * option to allocate a separate vmcs02 for each separate loaded vmcs12 - this
- * allows keeping them loaded on the processor, and in the future will allow
- * optimizations where prepare_vmcs02 doesn't need to set all the fields on
- * every entry if they never change.
- * So we keep, in vmx->nested.vmcs02_pool, a cache of size VMCS02_POOL_SIZE
- * (>=0) with a vmcs02 for each recently loaded vmcs12s, most recent first.
- *
- * The following functions allocate and free a vmcs02 in this pool.
- */
-
-/* Get a VMCS from the pool to use as vmcs02 for the current vmcs12. */
-static struct loaded_vmcs *nested_get_current_vmcs02(struct vcpu_vmx *vmx)
-{
- struct vmcs02_list *item;
- list_for_each_entry(item, &vmx->nested.vmcs02_pool, list)
- if (item->vmptr == vmx->nested.current_vmptr) {
- list_move(&item->list, &vmx->nested.vmcs02_pool);
- return &item->vmcs02;
- }
-
- if (vmx->nested.vmcs02_num >= max(VMCS02_POOL_SIZE, 1)) {
- /* Recycle the least recently used VMCS. */
- item = list_last_entry(&vmx->nested.vmcs02_pool,
- struct vmcs02_list, list);
- item->vmptr = vmx->nested.current_vmptr;
- list_move(&item->list, &vmx->nested.vmcs02_pool);
- return &item->vmcs02;
- }
-
- /* Create a new VMCS */
- item = kzalloc(sizeof(struct vmcs02_list), GFP_KERNEL);
- if (!item)
- return NULL;
- item->vmcs02.vmcs = alloc_vmcs();
- item->vmcs02.shadow_vmcs = NULL;
- if (!item->vmcs02.vmcs) {
- kfree(item);
- return NULL;
- }
- loaded_vmcs_init(&item->vmcs02);
- item->vmptr = vmx->nested.current_vmptr;
- list_add(&(item->list), &(vmx->nested.vmcs02_pool));
- vmx->nested.vmcs02_num++;
- return &item->vmcs02;
-}
-
-/* Free and remove from pool a vmcs02 saved for a vmcs12 (if there is one) */
-static void nested_free_vmcs02(struct vcpu_vmx *vmx, gpa_t vmptr)
-{
- struct vmcs02_list *item;
- list_for_each_entry(item, &vmx->nested.vmcs02_pool, list)
- if (item->vmptr == vmptr) {
- free_loaded_vmcs(&item->vmcs02);
- list_del(&item->list);
- kfree(item);
- vmx->nested.vmcs02_num--;
- return;
- }
-}
-
-/*
- * Free all VMCSs saved for this vcpu, except the one pointed by
- * vmx->loaded_vmcs. We must be running L1, so vmx->loaded_vmcs
- * must be &vmx->vmcs01.
- */
-static void nested_free_all_saved_vmcss(struct vcpu_vmx *vmx)
-{
- struct vmcs02_list *item, *n;
-
- WARN_ON(vmx->loaded_vmcs != &vmx->vmcs01);
- list_for_each_entry_safe(item, n, &vmx->nested.vmcs02_pool, list) {
- /*
- * Something will leak if the above WARN triggers. Better than
- * a use-after-free.
- */
- if (vmx->loaded_vmcs == &item->vmcs02)
- continue;
-
- free_loaded_vmcs(&item->vmcs02);
- list_del(&item->list);
- kfree(item);
- vmx->nested.vmcs02_num--;
- }
-}
-
/*
* The following 3 functions, nested_vmx_succeed()/failValid()/failInvalid(),
* set the success or error code of an emulated VMX instruction, as specified
@@ -7242,6 +7146,12 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmcs *shadow_vmcs;
+ vmx->nested.vmcs02.vmcs = alloc_vmcs();
+ vmx->nested.vmcs02.shadow_vmcs = NULL;
+ if (!vmx->nested.vmcs02.vmcs)
+ goto out_vmcs02;
+ loaded_vmcs_init(&vmx->nested.vmcs02);
+
if (cpu_has_vmx_msr_bitmap()) {
vmx->nested.msr_bitmap =
(unsigned long *)__get_free_page(GFP_KERNEL);
@@ -7264,9 +7174,6 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
vmx->vmcs01.shadow_vmcs = shadow_vmcs;
}
- INIT_LIST_HEAD(&(vmx->nested.vmcs02_pool));
- vmx->nested.vmcs02_num = 0;
-
hrtimer_init(&vmx->nested.preemption_timer, CLOCK_MONOTONIC,
HRTIMER_MODE_REL_PINNED);
vmx->nested.preemption_timer.function = vmx_preemption_timer_fn;
@@ -7281,6 +7188,9 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
free_page((unsigned long)vmx->nested.msr_bitmap);
out_msr_bitmap:
+ free_loaded_vmcs(&vmx->nested.vmcs02);
+
+out_vmcs02:
return -ENOMEM;
}
@@ -7434,7 +7344,7 @@ static void free_nested(struct vcpu_vmx *vmx)
vmx->vmcs01.shadow_vmcs = NULL;
}
kfree(vmx->nested.cached_vmcs12);
- /* Unpin physical memory we referred to in current vmcs02 */
+ /* Unpin physical memory we referred to in the vmcs02 */
if (vmx->nested.apic_access_page) {
kvm_release_page_dirty(vmx->nested.apic_access_page);
vmx->nested.apic_access_page = NULL;
@@ -7450,7 +7360,7 @@ static void free_nested(struct vcpu_vmx *vmx)
vmx->nested.pi_desc = NULL;
}
- nested_free_all_saved_vmcss(vmx);
+ free_loaded_vmcs(&vmx->nested.vmcs02);
}
/* Emulate the VMXOFF instruction */
@@ -7493,8 +7403,6 @@ static int handle_vmclear(struct kvm_vcpu *vcpu)
vmptr + offsetof(struct vmcs12, launch_state),
&zero, sizeof(zero));
- nested_free_vmcs02(vmx, vmptr);
-
nested_vmx_succeed(vcpu);
return kvm_skip_emulated_instruction(vcpu);
}
@@ -8406,10 +8314,11 @@ static bool nested_vmx_exit_reflected(struct kvm_vcpu *vcpu, u32 exit_reason)
/*
* The host physical addresses of some pages of guest memory
- * are loaded into VMCS02 (e.g. L1's Virtual APIC Page). The CPU
- * may write to these pages via their host physical address while
- * L2 is running, bypassing any address-translation-based dirty
- * tracking (e.g. EPT write protection).
+ * are loaded into the vmcs02 (e.g. vmcs12's Virtual APIC
+ * Page). The CPU may write to these pages via their host
+ * physical address while L2 is running, bypassing any
+ * address-translation-based dirty tracking (e.g. EPT write
+ * protection).
*
* Mark them dirty on every exit from L2 to prevent them from
* getting out of sync with dirty tracking.
@@ -10903,20 +10812,15 @@ static int enter_vmx_non_root_mode(struct kvm_vcpu *vcpu, bool from_vmentry)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
- struct loaded_vmcs *vmcs02;
u32 msr_entry_idx;
u32 exit_qual;
- vmcs02 = nested_get_current_vmcs02(vmx);
- if (!vmcs02)
- return -ENOMEM;
-
enter_guest_mode(vcpu);
if (!(vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS))
vmx->nested.vmcs01_debugctl = vmcs_read64(GUEST_IA32_DEBUGCTL);
- vmx_switch_vmcs(vcpu, vmcs02);
+ vmx_switch_vmcs(vcpu, &vmx->nested.vmcs02);
vmx_segment_cache_clear(vmx);
if (prepare_vmcs02(vcpu, vmcs12, from_vmentry, &exit_qual)) {
@@ -11534,10 +11438,6 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason,
vm_exit_controls_reset_shadow(vmx);
vmx_segment_cache_clear(vmx);
- /* if no vmcs02 cache requested, remove the one we used */
- if (VMCS02_POOL_SIZE == 0)
- nested_free_vmcs02(vmx, vmx->nested.current_vmptr);
-
/* Update any VMCS fields that might have changed while L2 ran */
vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, vmx->msr_autoload.nr);
vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, vmx->msr_autoload.nr);
--
2.14.3
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 3/3] KVM: VMX: make MSR bitmaps per-VCPU
2018-01-31 21:09 [PATCH v3 0/3] Per-VCPU MSR bitmaps patches - topic branch for x86/pti Paolo Bonzini
2018-01-31 21:09 ` [PATCH 1/3] KVM: nVMX: Eliminate vmcs02 pool Paolo Bonzini
2018-01-31 21:09 ` [PATCH 2/3] KVM: VMX: introduce alloc_loaded_vmcs Paolo Bonzini
@ 2018-01-31 21:09 ` Paolo Bonzini
2018-02-01 1:48 ` [PATCH v3 0/3] Per-VCPU MSR bitmaps patches - topic branch for x86/pti Konrad Rzeszutek Wilk
3 siblings, 0 replies; 6+ messages in thread
From: Paolo Bonzini @ 2018-01-31 21:09 UTC (permalink / raw)
To: linux-kernel, kvm
Cc: Radim Krčmář, David Woodhouse, KarimAllah Ahmed,
stable
Place the MSR bitmap in struct loaded_vmcs, and update it in place
every time the x2apic or APICv state can change. This is rare and
the loop can handle 64 MSRs per iteration, in a similar fashion as
nested_vmx_prepare_msr_bitmap.
This prepares for choosing, on a per-VM basis, whether to intercept
the SPEC_CTRL and PRED_CMD MSRs.
Cc: stable@vger.kernel.org # prereq for Spectre mitigation
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/vmx.c | 270 +++++++++++++++++++++++++++++------------------------
1 file changed, 147 insertions(+), 123 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index ab4b9bc99a52..896af99a8606 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -111,6 +111,14 @@ static u64 __read_mostly host_xss;
static bool __read_mostly enable_pml = 1;
module_param_named(pml, enable_pml, bool, S_IRUGO);
+#define MSR_TYPE_R 1
+#define MSR_TYPE_W 2
+#define MSR_TYPE_RW 3
+
+#define MSR_BITMAP_MODE_X2APIC 1
+#define MSR_BITMAP_MODE_X2APIC_APICV 2
+#define MSR_BITMAP_MODE_LM 4
+
#define KVM_VMX_TSC_MULTIPLIER_MAX 0xffffffffffffffffULL
/* Guest_tsc -> host_tsc conversion requires 64-bit division. */
@@ -209,6 +217,7 @@ struct loaded_vmcs {
int soft_vnmi_blocked;
ktime_t entry_time;
s64 vnmi_blocked_time;
+ unsigned long *msr_bitmap;
struct list_head loaded_vmcss_on_cpu_link;
};
@@ -449,8 +458,6 @@ struct nested_vmx {
bool pi_pending;
u16 posted_intr_nv;
- unsigned long *msr_bitmap;
-
struct hrtimer preemption_timer;
bool preemption_timer_expired;
@@ -573,6 +580,7 @@ struct vcpu_vmx {
struct kvm_vcpu vcpu;
unsigned long host_rsp;
u8 fail;
+ u8 msr_bitmap_mode;
u32 exit_intr_info;
u32 idt_vectoring_info;
ulong rflags;
@@ -927,6 +935,7 @@ static bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu);
static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12,
u16 error_code);
+static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu);
static DEFINE_PER_CPU(struct vmcs *, vmxarea);
static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
@@ -946,12 +955,6 @@ static DEFINE_PER_CPU(spinlock_t, blocked_vcpu_on_cpu_lock);
enum {
VMX_IO_BITMAP_A,
VMX_IO_BITMAP_B,
- VMX_MSR_BITMAP_LEGACY,
- VMX_MSR_BITMAP_LONGMODE,
- VMX_MSR_BITMAP_LEGACY_X2APIC_APICV,
- VMX_MSR_BITMAP_LONGMODE_X2APIC_APICV,
- VMX_MSR_BITMAP_LEGACY_X2APIC,
- VMX_MSR_BITMAP_LONGMODE_X2APIC,
VMX_VMREAD_BITMAP,
VMX_VMWRITE_BITMAP,
VMX_BITMAP_NR
@@ -961,12 +964,6 @@ static unsigned long *vmx_bitmap[VMX_BITMAP_NR];
#define vmx_io_bitmap_a (vmx_bitmap[VMX_IO_BITMAP_A])
#define vmx_io_bitmap_b (vmx_bitmap[VMX_IO_BITMAP_B])
-#define vmx_msr_bitmap_legacy (vmx_bitmap[VMX_MSR_BITMAP_LEGACY])
-#define vmx_msr_bitmap_longmode (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE])
-#define vmx_msr_bitmap_legacy_x2apic_apicv (vmx_bitmap[VMX_MSR_BITMAP_LEGACY_X2APIC_APICV])
-#define vmx_msr_bitmap_longmode_x2apic_apicv (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE_X2APIC_APICV])
-#define vmx_msr_bitmap_legacy_x2apic (vmx_bitmap[VMX_MSR_BITMAP_LEGACY_X2APIC])
-#define vmx_msr_bitmap_longmode_x2apic (vmx_bitmap[VMX_MSR_BITMAP_LONGMODE_X2APIC])
#define vmx_vmread_bitmap (vmx_bitmap[VMX_VMREAD_BITMAP])
#define vmx_vmwrite_bitmap (vmx_bitmap[VMX_VMWRITE_BITMAP])
@@ -2564,36 +2561,6 @@ static void move_msr_up(struct vcpu_vmx *vmx, int from, int to)
vmx->guest_msrs[from] = tmp;
}
-static void vmx_set_msr_bitmap(struct kvm_vcpu *vcpu)
-{
- unsigned long *msr_bitmap;
-
- if (is_guest_mode(vcpu))
- msr_bitmap = to_vmx(vcpu)->nested.msr_bitmap;
- else if (cpu_has_secondary_exec_ctrls() &&
- (vmcs_read32(SECONDARY_VM_EXEC_CONTROL) &
- SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
- if (enable_apicv && kvm_vcpu_apicv_active(vcpu)) {
- if (is_long_mode(vcpu))
- msr_bitmap = vmx_msr_bitmap_longmode_x2apic_apicv;
- else
- msr_bitmap = vmx_msr_bitmap_legacy_x2apic_apicv;
- } else {
- if (is_long_mode(vcpu))
- msr_bitmap = vmx_msr_bitmap_longmode_x2apic;
- else
- msr_bitmap = vmx_msr_bitmap_legacy_x2apic;
- }
- } else {
- if (is_long_mode(vcpu))
- msr_bitmap = vmx_msr_bitmap_longmode;
- else
- msr_bitmap = vmx_msr_bitmap_legacy;
- }
-
- vmcs_write64(MSR_BITMAP, __pa(msr_bitmap));
-}
-
/*
* Set up the vmcs to automatically save and restore system
* msrs. Don't touch the 64-bit msrs if the guest is in legacy
@@ -2634,7 +2601,7 @@ static void setup_msrs(struct vcpu_vmx *vmx)
vmx->save_nmsrs = save_nmsrs;
if (cpu_has_vmx_msr_bitmap())
- vmx_set_msr_bitmap(&vmx->vcpu);
+ vmx_update_msr_bitmap(&vmx->vcpu);
}
/*
@@ -3844,6 +3811,8 @@ static void free_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
loaded_vmcs_clear(loaded_vmcs);
free_vmcs(loaded_vmcs->vmcs);
loaded_vmcs->vmcs = NULL;
+ if (loaded_vmcs->msr_bitmap)
+ free_page((unsigned long)loaded_vmcs->msr_bitmap);
WARN_ON(loaded_vmcs->shadow_vmcs != NULL);
}
@@ -3860,7 +3829,18 @@ static int alloc_loaded_vmcs(struct loaded_vmcs *loaded_vmcs)
loaded_vmcs->shadow_vmcs = NULL;
loaded_vmcs_init(loaded_vmcs);
+
+ if (cpu_has_vmx_msr_bitmap()) {
+ loaded_vmcs->msr_bitmap = (unsigned long *)__get_free_page(GFP_KERNEL);
+ if (!loaded_vmcs->msr_bitmap)
+ goto out_vmcs;
+ memset(loaded_vmcs->msr_bitmap, 0xff, PAGE_SIZE);
+ }
return 0;
+
+out_vmcs:
+ free_loaded_vmcs(loaded_vmcs);
+ return -ENOMEM;
}
static void free_kvm_area(void)
@@ -4921,10 +4901,8 @@ static void free_vpid(int vpid)
spin_unlock(&vmx_vpid_lock);
}
-#define MSR_TYPE_R 1
-#define MSR_TYPE_W 2
-static void __vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
- u32 msr, int type)
+static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
+ u32 msr, int type)
{
int f = sizeof(unsigned long);
@@ -4958,6 +4936,50 @@ static void __vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
}
}
+static void __always_inline vmx_enable_intercept_for_msr(unsigned long *msr_bitmap,
+ u32 msr, int type)
+{
+ int f = sizeof(unsigned long);
+
+ if (!cpu_has_vmx_msr_bitmap())
+ return;
+
+ /*
+ * See Intel PRM Vol. 3, 20.6.9 (MSR-Bitmap Address). Early manuals
+ * have the write-low and read-high bitmap offsets the wrong way round.
+ * We can control MSRs 0x00000000-0x00001fff and 0xc0000000-0xc0001fff.
+ */
+ if (msr <= 0x1fff) {
+ if (type & MSR_TYPE_R)
+ /* read-low */
+ __set_bit(msr, msr_bitmap + 0x000 / f);
+
+ if (type & MSR_TYPE_W)
+ /* write-low */
+ __set_bit(msr, msr_bitmap + 0x800 / f);
+
+ } else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) {
+ msr &= 0x1fff;
+ if (type & MSR_TYPE_R)
+ /* read-high */
+ __set_bit(msr, msr_bitmap + 0x400 / f);
+
+ if (type & MSR_TYPE_W)
+ /* write-high */
+ __set_bit(msr, msr_bitmap + 0xc00 / f);
+
+ }
+}
+
+static void __always_inline vmx_set_intercept_for_msr(unsigned long *msr_bitmap,
+ u32 msr, int type, bool value)
+{
+ if (value)
+ vmx_enable_intercept_for_msr(msr_bitmap, msr, type);
+ else
+ vmx_disable_intercept_for_msr(msr_bitmap, msr, type);
+}
+
/*
* If a msr is allowed by L0, we should check whether it is allowed by L1.
* The corresponding bit will be cleared unless both of L0 and L1 allow it.
@@ -5004,30 +5026,70 @@ static void nested_vmx_disable_intercept_for_msr(unsigned long *msr_bitmap_l1,
}
}
-static void vmx_disable_intercept_for_msr(u32 msr, bool longmode_only)
+static u8 vmx_msr_bitmap_mode(struct kvm_vcpu *vcpu)
{
- if (!longmode_only)
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy,
- msr, MSR_TYPE_R | MSR_TYPE_W);
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode,
- msr, MSR_TYPE_R | MSR_TYPE_W);
+ u8 mode = 0;
+
+ if (cpu_has_secondary_exec_ctrls() &&
+ (vmcs_read32(SECONDARY_VM_EXEC_CONTROL) &
+ SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE)) {
+ mode |= MSR_BITMAP_MODE_X2APIC;
+ if (enable_apicv && kvm_vcpu_apicv_active(vcpu))
+ mode |= MSR_BITMAP_MODE_X2APIC_APICV;
+ }
+
+ if (is_long_mode(vcpu))
+ mode |= MSR_BITMAP_MODE_LM;
+
+ return mode;
}
-static void vmx_disable_intercept_msr_x2apic(u32 msr, int type, bool apicv_active)
+#define X2APIC_MSR(r) (APIC_BASE_MSR + ((r) >> 4))
+
+static void vmx_update_msr_bitmap_x2apic(unsigned long *msr_bitmap,
+ u8 mode)
{
- if (apicv_active) {
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic_apicv,
- msr, type);
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic_apicv,
- msr, type);
- } else {
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_legacy_x2apic,
- msr, type);
- __vmx_disable_intercept_for_msr(vmx_msr_bitmap_longmode_x2apic,
- msr, type);
+ int msr;
+
+ for (msr = 0x800; msr <= 0x8ff; msr += BITS_PER_LONG) {
+ unsigned word = msr / BITS_PER_LONG;
+ msr_bitmap[word] = (mode & MSR_BITMAP_MODE_X2APIC_APICV) ? 0 : ~0;
+ msr_bitmap[word + (0x800 / sizeof(long))] = ~0;
+ }
+
+ if (mode & MSR_BITMAP_MODE_X2APIC) {
+ /*
+ * TPR reads and writes can be virtualized even if virtual interrupt
+ * delivery is not in use.
+ */
+ vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TASKPRI), MSR_TYPE_RW);
+ if (mode & MSR_BITMAP_MODE_X2APIC_APICV) {
+ vmx_enable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_TMCCT), MSR_TYPE_R);
+ vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_EOI), MSR_TYPE_W);
+ vmx_disable_intercept_for_msr(msr_bitmap, X2APIC_MSR(APIC_SELF_IPI), MSR_TYPE_W);
+ }
}
}
+static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+ unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;
+ u8 mode = vmx_msr_bitmap_mode(vcpu);
+ u8 changed = mode ^ vmx->msr_bitmap_mode;
+
+ if (!changed)
+ return;
+
+ vmx_set_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW,
+ !(mode & MSR_BITMAP_MODE_LM));
+
+ if (changed & (MSR_BITMAP_MODE_X2APIC | MSR_BITMAP_MODE_X2APIC_APICV))
+ vmx_update_msr_bitmap_x2apic(msr_bitmap, mode);
+
+ vmx->msr_bitmap_mode = mode;
+}
+
static bool vmx_get_enable_apicv(struct kvm_vcpu *vcpu)
{
return enable_apicv;
@@ -5277,7 +5339,7 @@ static void vmx_refresh_apicv_exec_ctrl(struct kvm_vcpu *vcpu)
}
if (cpu_has_vmx_msr_bitmap())
- vmx_set_msr_bitmap(vcpu);
+ vmx_update_msr_bitmap(vcpu);
}
static u32 vmx_exec_control(struct vcpu_vmx *vmx)
@@ -5464,7 +5526,7 @@ static void vmx_vcpu_setup(struct vcpu_vmx *vmx)
vmcs_write64(VMWRITE_BITMAP, __pa(vmx_vmwrite_bitmap));
}
if (cpu_has_vmx_msr_bitmap())
- vmcs_write64(MSR_BITMAP, __pa(vmx_msr_bitmap_legacy));
+ vmcs_write64(MSR_BITMAP, __pa(vmx->vmcs01.msr_bitmap));
vmcs_write64(VMCS_LINK_POINTER, -1ull); /* 22.3.1.5 */
@@ -6747,7 +6809,7 @@ void vmx_enable_tdp(void)
static __init int hardware_setup(void)
{
- int r = -ENOMEM, i, msr;
+ int r = -ENOMEM, i;
rdmsrl_safe(MSR_EFER, &host_efer);
@@ -6767,9 +6829,6 @@ static __init int hardware_setup(void)
memset(vmx_io_bitmap_b, 0xff, PAGE_SIZE);
- memset(vmx_msr_bitmap_legacy, 0xff, PAGE_SIZE);
- memset(vmx_msr_bitmap_longmode, 0xff, PAGE_SIZE);
-
if (setup_vmcs_config(&vmcs_config) < 0) {
r = -EIO;
goto out;
@@ -6838,42 +6897,8 @@ static __init int hardware_setup(void)
kvm_tsc_scaling_ratio_frac_bits = 48;
}
- vmx_disable_intercept_for_msr(MSR_FS_BASE, false);
- vmx_disable_intercept_for_msr(MSR_GS_BASE, false);
- vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true);
- vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_CS, false);
- vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_ESP, false);
- vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false);
-
- memcpy(vmx_msr_bitmap_legacy_x2apic_apicv,
- vmx_msr_bitmap_legacy, PAGE_SIZE);
- memcpy(vmx_msr_bitmap_longmode_x2apic_apicv,
- vmx_msr_bitmap_longmode, PAGE_SIZE);
- memcpy(vmx_msr_bitmap_legacy_x2apic,
- vmx_msr_bitmap_legacy, PAGE_SIZE);
- memcpy(vmx_msr_bitmap_longmode_x2apic,
- vmx_msr_bitmap_longmode, PAGE_SIZE);
-
set_bit(0, vmx_vpid_bitmap); /* 0 is reserved for host */
- for (msr = 0x800; msr <= 0x8ff; msr++) {
- if (msr == 0x839 /* TMCCT */)
- continue;
- vmx_disable_intercept_msr_x2apic(msr, MSR_TYPE_R, true);
- }
-
- /*
- * TPR reads and writes can be virtualized even if virtual interrupt
- * delivery is not in use.
- */
- vmx_disable_intercept_msr_x2apic(0x808, MSR_TYPE_W, true);
- vmx_disable_intercept_msr_x2apic(0x808, MSR_TYPE_R | MSR_TYPE_W, false);
-
- /* EOI */
- vmx_disable_intercept_msr_x2apic(0x80b, MSR_TYPE_W, true);
- /* SELF-IPI */
- vmx_disable_intercept_msr_x2apic(0x83f, MSR_TYPE_W, true);
-
if (enable_ept)
vmx_enable_tdp();
else
@@ -7162,13 +7187,6 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
if (r < 0)
goto out_vmcs02;
- if (cpu_has_vmx_msr_bitmap()) {
- vmx->nested.msr_bitmap =
- (unsigned long *)__get_free_page(GFP_KERNEL);
- if (!vmx->nested.msr_bitmap)
- goto out_msr_bitmap;
- }
-
vmx->nested.cached_vmcs12 = kmalloc(VMCS12_SIZE, GFP_KERNEL);
if (!vmx->nested.cached_vmcs12)
goto out_cached_vmcs12;
@@ -7195,9 +7213,6 @@ static int enter_vmx_operation(struct kvm_vcpu *vcpu)
kfree(vmx->nested.cached_vmcs12);
out_cached_vmcs12:
- free_page((unsigned long)vmx->nested.msr_bitmap);
-
-out_msr_bitmap:
free_loaded_vmcs(&vmx->nested.vmcs02);
out_vmcs02:
@@ -7343,10 +7358,6 @@ static void free_nested(struct vcpu_vmx *vmx)
free_vpid(vmx->nested.vpid02);
vmx->nested.posted_intr_nv = -1;
vmx->nested.current_vmptr = -1ull;
- if (vmx->nested.msr_bitmap) {
- free_page((unsigned long)vmx->nested.msr_bitmap);
- vmx->nested.msr_bitmap = NULL;
- }
if (enable_shadow_vmcs) {
vmx_disable_shadow_vmcs(vmx);
vmcs_clear(vmx->vmcs01.shadow_vmcs);
@@ -8862,7 +8873,7 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
}
vmcs_write32(SECONDARY_VM_EXEC_CONTROL, sec_exec_control);
- vmx_set_msr_bitmap(vcpu);
+ vmx_update_msr_bitmap(vcpu);
}
static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu, hpa_t hpa)
@@ -9523,6 +9534,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
{
int err;
struct vcpu_vmx *vmx = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
+ unsigned long *msr_bitmap;
int cpu;
if (!vmx)
@@ -9559,6 +9571,15 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id)
if (err < 0)
goto free_msrs;
+ msr_bitmap = vmx->vmcs01.msr_bitmap;
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_FS_BASE, MSR_TYPE_RW);
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_GS_BASE, MSR_TYPE_RW);
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_KERNEL_GS_BASE, MSR_TYPE_RW);
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_CS, MSR_TYPE_RW);
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_ESP, MSR_TYPE_RW);
+ vmx_disable_intercept_for_msr(msr_bitmap, MSR_IA32_SYSENTER_EIP, MSR_TYPE_RW);
+ vmx->msr_bitmap_mode = 0;
+
vmx->loaded_vmcs = &vmx->vmcs01;
cpu = get_cpu();
vmx_vcpu_load(&vmx->vcpu, cpu);
@@ -10022,7 +10043,7 @@ static inline bool nested_vmx_merge_msr_bitmap(struct kvm_vcpu *vcpu,
int msr;
struct page *page;
unsigned long *msr_bitmap_l1;
- unsigned long *msr_bitmap_l0 = to_vmx(vcpu)->nested.msr_bitmap;
+ unsigned long *msr_bitmap_l0 = to_vmx(vcpu)->nested.vmcs02.msr_bitmap;
/* This shortcut is ok because we support only x2APIC MSRs so far. */
if (!nested_cpu_has_virt_x2apic_mode(vmcs12))
@@ -10599,6 +10620,9 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
if (kvm_has_tsc_control)
decache_tsc_multiplier(vmx);
+ if (cpu_has_vmx_msr_bitmap())
+ vmcs_write64(MSR_BITMAP, __pa(vmx->nested.vmcs02.msr_bitmap));
+
if (enable_vpid) {
/*
* There is no direct mapping between vpid02 and vpid12, the
@@ -11397,7 +11421,7 @@ static void load_vmcs12_host_state(struct kvm_vcpu *vcpu,
vmcs_write64(GUEST_IA32_DEBUGCTL, 0);
if (cpu_has_vmx_msr_bitmap())
- vmx_set_msr_bitmap(vcpu);
+ vmx_update_msr_bitmap(vcpu);
if (nested_vmx_load_msr(vcpu, vmcs12->vm_exit_msr_load_addr,
vmcs12->vm_exit_msr_load_count))
--
2.14.3
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