* [PATCH v2 1/2] kvm: update kernel headers for KVM_{GET|SET}_SREGS2
2021-04-26 11:58 [PATCH v2 0/2] kvm: use KVM_{GET|SET}_SREGS2 when available Maxim Levitsky
@ 2021-04-26 11:58 ` Maxim Levitsky
2021-04-26 11:58 ` [PATCH v2 2/2] KVM: use KVM_{GET|SET}_SREGS2 when supported Maxim Levitsky
1 sibling, 0 replies; 3+ messages in thread
From: Maxim Levitsky @ 2021-04-26 11:58 UTC (permalink / raw)
To: qemu-devel
Cc: Cornelia Huck, Eduardo Habkost, kvm, Michael S. Tsirkin,
Marcelo Tosatti, Richard Henderson, Maxim Levitsky, Paolo Bonzini
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
| 13 +++++++++++++
| 5 +++++
2 files changed, 18 insertions(+)
--git a/linux-headers/asm-x86/kvm.h b/linux-headers/asm-x86/kvm.h
index 8e76d3701d..d61dc76e24 100644
--- a/linux-headers/asm-x86/kvm.h
+++ b/linux-headers/asm-x86/kvm.h
@@ -158,6 +158,19 @@ struct kvm_sregs {
__u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64];
};
+struct kvm_sregs2 {
+ /* out (KVM_GET_SREGS2) / in (KVM_SET_SREGS2) */
+ struct kvm_segment cs, ds, es, fs, gs, ss;
+ struct kvm_segment tr, ldt;
+ struct kvm_dtable gdt, idt;
+ __u64 cr0, cr2, cr3, cr4, cr8;
+ __u64 efer;
+ __u64 apic_base;
+ __u64 flags;
+ __u64 pdptrs[4];
+};
+#define KVM_SREGS2_FLAGS_PDPTRS_VALID 1
+
/* for KVM_GET_FPU and KVM_SET_FPU */
struct kvm_fpu {
__u8 fpr[8][16];
--git a/linux-headers/linux/kvm.h b/linux-headers/linux/kvm.h
index 020b62a619..22ea29a243 100644
--- a/linux-headers/linux/kvm.h
+++ b/linux-headers/linux/kvm.h
@@ -1056,6 +1056,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_ENFORCE_PV_FEATURE_CPUID 190
#define KVM_CAP_SYS_HYPERV_CPUID 191
#define KVM_CAP_DIRTY_LOG_RING 192
+#define KVM_CAP_SREGS2 199
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1563,6 +1564,10 @@ struct kvm_pv_cmd {
/* Available with KVM_CAP_DIRTY_LOG_RING */
#define KVM_RESET_DIRTY_RINGS _IO(KVMIO, 0xc7)
+
+#define KVM_GET_SREGS2 _IOR(KVMIO, 0xcc, struct kvm_sregs2)
+#define KVM_SET_SREGS2 _IOW(KVMIO, 0xcd, struct kvm_sregs2)
+
/* Secure Encrypted Virtualization command */
enum sev_cmd_id {
/* Guest initialization commands */
--
2.26.2
^ permalink raw reply related [flat|nested] 3+ messages in thread* [PATCH v2 2/2] KVM: use KVM_{GET|SET}_SREGS2 when supported.
2021-04-26 11:58 [PATCH v2 0/2] kvm: use KVM_{GET|SET}_SREGS2 when available Maxim Levitsky
2021-04-26 11:58 ` [PATCH v2 1/2] kvm: update kernel headers for KVM_{GET|SET}_SREGS2 Maxim Levitsky
@ 2021-04-26 11:58 ` Maxim Levitsky
1 sibling, 0 replies; 3+ messages in thread
From: Maxim Levitsky @ 2021-04-26 11:58 UTC (permalink / raw)
To: qemu-devel
Cc: Cornelia Huck, Eduardo Habkost, kvm, Michael S. Tsirkin,
Marcelo Tosatti, Richard Henderson, Maxim Levitsky, Paolo Bonzini
This allows to make PDPTRs part of the migration
stream and thus not reload them after migration which
is against X86 spec.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
accel/kvm/kvm-all.c | 5 ++
include/sysemu/kvm.h | 4 ++
target/i386/cpu.h | 3 ++
target/i386/kvm/kvm.c | 107 +++++++++++++++++++++++++++++++++++++++++-
target/i386/machine.c | 30 ++++++++++++
5 files changed, 147 insertions(+), 2 deletions(-)
diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index b6d9f92f15..0397b3cb2b 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -142,6 +142,7 @@ bool kvm_msi_via_irqfd_allowed;
bool kvm_gsi_routing_allowed;
bool kvm_gsi_direct_mapping;
bool kvm_allowed;
+bool kvm_sregs2;
bool kvm_readonly_mem_allowed;
bool kvm_vm_attributes_allowed;
bool kvm_direct_msi_allowed;
@@ -2186,6 +2187,10 @@ static int kvm_init(MachineState *ms)
kvm_ioeventfd_any_length_allowed =
(kvm_check_extension(s, KVM_CAP_IOEVENTFD_ANY_LENGTH) > 0);
+
+ kvm_sregs2 =
+ (kvm_check_extension(s, KVM_CAP_SREGS2) > 0);
+
kvm_state = s;
ret = kvm_arch_init(ms, s);
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index a1ab1ee12d..b3d4538c55 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -32,6 +32,7 @@
#ifdef CONFIG_KVM_IS_POSSIBLE
extern bool kvm_allowed;
+extern bool kvm_sregs2;
extern bool kvm_kernel_irqchip;
extern bool kvm_split_irqchip;
extern bool kvm_async_interrupts_allowed;
@@ -139,6 +140,9 @@ extern bool kvm_msi_use_devid;
*/
#define kvm_gsi_direct_mapping() (kvm_gsi_direct_mapping)
+
+#define kvm_supports_sregs2() (kvm_sregs2)
+
/**
* kvm_readonly_mem_enabled:
*
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 570f916878..ac877097d4 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1422,6 +1422,9 @@ typedef struct CPUX86State {
SegmentCache idt; /* only base and limit are used */
target_ulong cr[5]; /* NOTE: cr1 is unused */
+
+ bool pdptrs_valid;
+ uint64_t pdptrs[4];
int32_t a20_mask;
BNDReg bnd_regs[4];
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 7fe9f52710..93570706e1 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -2514,6 +2514,61 @@ static int kvm_put_sregs(X86CPU *cpu)
return kvm_vcpu_ioctl(CPU(cpu), KVM_SET_SREGS, &sregs);
}
+static int kvm_put_sregs2(X86CPU *cpu)
+{
+ CPUX86State *env = &cpu->env;
+ struct kvm_sregs2 sregs;
+ int i;
+
+ sregs.flags = 0;
+
+ if ((env->eflags & VM_MASK)) {
+ set_v8086_seg(&sregs.cs, &env->segs[R_CS]);
+ set_v8086_seg(&sregs.ds, &env->segs[R_DS]);
+ set_v8086_seg(&sregs.es, &env->segs[R_ES]);
+ set_v8086_seg(&sregs.fs, &env->segs[R_FS]);
+ set_v8086_seg(&sregs.gs, &env->segs[R_GS]);
+ set_v8086_seg(&sregs.ss, &env->segs[R_SS]);
+ } else {
+ set_seg(&sregs.cs, &env->segs[R_CS]);
+ set_seg(&sregs.ds, &env->segs[R_DS]);
+ set_seg(&sregs.es, &env->segs[R_ES]);
+ set_seg(&sregs.fs, &env->segs[R_FS]);
+ set_seg(&sregs.gs, &env->segs[R_GS]);
+ set_seg(&sregs.ss, &env->segs[R_SS]);
+ }
+
+ set_seg(&sregs.tr, &env->tr);
+ set_seg(&sregs.ldt, &env->ldt);
+
+ sregs.idt.limit = env->idt.limit;
+ sregs.idt.base = env->idt.base;
+ memset(sregs.idt.padding, 0, sizeof sregs.idt.padding);
+ sregs.gdt.limit = env->gdt.limit;
+ sregs.gdt.base = env->gdt.base;
+ memset(sregs.gdt.padding, 0, sizeof sregs.gdt.padding);
+
+ sregs.cr0 = env->cr[0];
+ sregs.cr2 = env->cr[2];
+ sregs.cr3 = env->cr[3];
+ sregs.cr4 = env->cr[4];
+
+ sregs.cr8 = cpu_get_apic_tpr(cpu->apic_state);
+ sregs.apic_base = cpu_get_apic_base(cpu->apic_state);
+
+ sregs.efer = env->efer;
+
+ if (env->pdptrs_valid) {
+ for (i = 0; i < 4; i++) {
+ sregs.pdptrs[i] = env->pdptrs[i];
+ }
+ sregs.flags |= KVM_SREGS2_FLAGS_PDPTRS_VALID;
+ }
+
+ return kvm_vcpu_ioctl(CPU(cpu), KVM_SET_SREGS2, &sregs);
+}
+
+
static void kvm_msr_buf_reset(X86CPU *cpu)
{
memset(cpu->kvm_msr_buf, 0, MSR_BUF_SIZE);
@@ -3175,6 +3230,53 @@ static int kvm_get_sregs(X86CPU *cpu)
return 0;
}
+static int kvm_get_sregs2(X86CPU *cpu)
+{
+ CPUX86State *env = &cpu->env;
+ struct kvm_sregs2 sregs;
+ int i, ret;
+
+ ret = kvm_vcpu_ioctl(CPU(cpu), KVM_GET_SREGS2, &sregs);
+ if (ret < 0) {
+ return ret;
+ }
+
+ get_seg(&env->segs[R_CS], &sregs.cs);
+ get_seg(&env->segs[R_DS], &sregs.ds);
+ get_seg(&env->segs[R_ES], &sregs.es);
+ get_seg(&env->segs[R_FS], &sregs.fs);
+ get_seg(&env->segs[R_GS], &sregs.gs);
+ get_seg(&env->segs[R_SS], &sregs.ss);
+
+ get_seg(&env->tr, &sregs.tr);
+ get_seg(&env->ldt, &sregs.ldt);
+
+ env->idt.limit = sregs.idt.limit;
+ env->idt.base = sregs.idt.base;
+ env->gdt.limit = sregs.gdt.limit;
+ env->gdt.base = sregs.gdt.base;
+
+ env->cr[0] = sregs.cr0;
+ env->cr[2] = sregs.cr2;
+ env->cr[3] = sregs.cr3;
+ env->cr[4] = sregs.cr4;
+
+ env->efer = sregs.efer;
+
+ env->pdptrs_valid = sregs.flags & KVM_SREGS2_FLAGS_PDPTRS_VALID;
+
+ if (env->pdptrs_valid) {
+ for (i = 0; i < 4; i++) {
+ env->pdptrs[i] = sregs.pdptrs[i];
+ }
+ }
+
+ /* changes to apic base and cr8/tpr are read back via kvm_arch_post_run */
+ x86_update_hflags(env);
+
+ return 0;
+}
+
static int kvm_get_msrs(X86CPU *cpu)
{
CPUX86State *env = &cpu->env;
@@ -4000,7 +4102,8 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
assert(cpu_is_stopped(cpu) || qemu_cpu_is_self(cpu));
/* must be before kvm_put_nested_state so that EFER.SVME is set */
- ret = kvm_put_sregs(x86_cpu);
+ ret = kvm_supports_sregs2() ? kvm_put_sregs2(x86_cpu) :
+ kvm_put_sregs(x86_cpu);
if (ret < 0) {
return ret;
}
@@ -4105,7 +4208,7 @@ int kvm_arch_get_registers(CPUState *cs)
if (ret < 0) {
goto out;
}
- ret = kvm_get_sregs(cpu);
+ ret = kvm_supports_sregs2() ? kvm_get_sregs2(cpu) : kvm_get_sregs(cpu);
if (ret < 0) {
goto out;
}
diff --git a/target/i386/machine.c b/target/i386/machine.c
index 137604ddb8..ae0144cf34 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -1396,6 +1396,35 @@ static const VMStateDescription vmstate_msr_tsx_ctrl = {
}
};
+static bool pdptrs_needed(void *opaque)
+{
+ X86CPU *cpu = opaque;
+ CPUX86State *env = &cpu->env;
+ return env->pdptrs_valid;
+}
+
+static int pdptrs_post_load(void *opaque, int version_id)
+{
+ X86CPU *cpu = opaque;
+ CPUX86State *env = &cpu->env;
+ env->pdptrs_valid = true;
+ return 0;
+}
+
+
+static const VMStateDescription vmstate_pdptrs = {
+ .name = "cpu/pdptrs",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .needed = pdptrs_needed,
+ .post_load = pdptrs_post_load,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64_ARRAY(env.pdptrs, X86CPU, 4),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+
VMStateDescription vmstate_x86_cpu = {
.name = "cpu",
.version_id = 12,
@@ -1531,6 +1560,7 @@ VMStateDescription vmstate_x86_cpu = {
&vmstate_nested_state,
#endif
&vmstate_msr_tsx_ctrl,
+ &vmstate_pdptrs,
NULL
}
};
--
2.26.2
^ permalink raw reply related [flat|nested] 3+ messages in thread