From 28cf1b55f346a9f56e84fa57921f5a28a99cd59b Mon Sep 17 00:00:00 2001
From: Jing Liu <jing2.liu@intel.com>
Date: Wed, 16 Feb 2022 22:04:32 -0800
Subject: [PATCH 10/24] x86: add support for KVM_CAP_XSAVE2 and AMX state
migration
RH-Author: Paul Lai <plai@redhat.com>
RH-MergeRequest: 176: Enable KVM AMX support
RH-Commit: [10/13] d584f455ba1ecd8a4a87f3470e6aac24ba9a1f5a
RH-Bugzilla: 1916415
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
RH-Acked-by: Igor Mammedov <imammedo@redhat.com>
RH-Acked-by: Paolo Bonzini <pbonzini@redhat.com>
When dynamic xfeatures (e.g. AMX) are used by the guest, the xsave
area would be larger than 4KB. KVM_GET_XSAVE2 and KVM_SET_XSAVE
under KVM_CAP_XSAVE2 works with a xsave buffer larger than 4KB.
Always use the new ioctls under KVM_CAP_XSAVE2 when KVM supports it.
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Zeng Guang <guang.zeng@intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220217060434.52460-7-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit e56dd3c70abb31893c61ac834109fa7a38841330)
Signed-off-by: Paul Lai <plai@redhat.com>
---
target/i386/cpu.h | 4 ++++
target/i386/kvm/kvm.c | 42 ++++++++++++++++++++++++--------------
target/i386/xsave_helper.c | 28 +++++++++++++++++++++++++
3 files changed, 59 insertions(+), 15 deletions(-)
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index f2bdef9c26..14a3501b87 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1522,6 +1522,10 @@ typedef struct CPUX86State {
uint64_t opmask_regs[NB_OPMASK_REGS];
YMMReg zmmh_regs[CPU_NB_REGS];
ZMMReg hi16_zmm_regs[CPU_NB_REGS];
+#ifdef TARGET_X86_64
+ uint8_t xtilecfg[64];
+ uint8_t xtiledata[8192];
+#endif
/* sysenter registers */
uint32_t sysenter_cs;
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index a64a79d870..d3d476df27 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -123,6 +123,7 @@ static uint32_t num_architectural_pmu_gp_counters;
static uint32_t num_architectural_pmu_fixed_counters;
static int has_xsave;
+static int has_xsave2;
static int has_xcrs;
static int has_pit_state2;
static int has_exception_payload;
@@ -1585,6 +1586,26 @@ static Error *invtsc_mig_blocker;
#define KVM_MAX_CPUID_ENTRIES 100
+static void kvm_init_xsave(CPUX86State *env)
+{
+ if (has_xsave2) {
+ env->xsave_buf_len = QEMU_ALIGN_UP(has_xsave2, 4096);
+ } else if (has_xsave) {
+ env->xsave_buf_len = sizeof(struct kvm_xsave);
+ } else {
+ return;
+ }
+
+ env->xsave_buf = qemu_memalign(4096, env->xsave_buf_len);
+ memset(env->xsave_buf, 0, env->xsave_buf_len);
+ /*
+ * The allocated storage must be large enough for all of the
+ * possible XSAVE state components.
+ */
+ assert(kvm_arch_get_supported_cpuid(kvm_state, 0xd, 0, R_ECX) <=
+ env->xsave_buf_len);
+}
+
int kvm_arch_init_vcpu(CPUState *cs)
{
struct {
@@ -1614,6 +1635,8 @@ int kvm_arch_init_vcpu(CPUState *cs)
cpuid_i = 0;
+ has_xsave2 = kvm_check_extension(cs->kvm_state, KVM_CAP_XSAVE2);
+
r = kvm_arch_set_tsc_khz(cs);
if (r < 0) {
return r;
@@ -2003,19 +2026,7 @@ int kvm_arch_init_vcpu(CPUState *cs)
if (r) {
goto fail;
}
-
- if (has_xsave) {
- env->xsave_buf_len = sizeof(struct kvm_xsave);
- env->xsave_buf = qemu_memalign(4096, env->xsave_buf_len);
- memset(env->xsave_buf, 0, env->xsave_buf_len);
-
- /*
- * The allocated storage must be large enough for all of the
- * possible XSAVE state components.
- */
- assert(kvm_arch_get_supported_cpuid(kvm_state, 0xd, 0, R_ECX)
- <= env->xsave_buf_len);
- }
+ kvm_init_xsave(env);
max_nested_state_len = kvm_max_nested_state_length();
if (max_nested_state_len > 0) {
@@ -3263,13 +3274,14 @@ static int kvm_get_xsave(X86CPU *cpu)
{
CPUX86State *env = &cpu->env;
void *xsave = env->xsave_buf;
- int ret;
+ int type, ret;
if (!has_xsave) {
return kvm_get_fpu(cpu);
}
- ret = kvm_vcpu_ioctl(CPU(cpu), KVM_GET_XSAVE, xsave);
+ type = has_xsave2 ? KVM_GET_XSAVE2 : KVM_GET_XSAVE;
+ ret = kvm_vcpu_ioctl(CPU(cpu), type, xsave);
if (ret < 0) {
return ret;
}
diff --git a/target/i386/xsave_helper.c b/target/i386/xsave_helper.c
index ac61a96344..996e9f3bfe 100644
--- a/target/i386/xsave_helper.c
+++ b/target/i386/xsave_helper.c
@@ -126,6 +126,20 @@ void x86_cpu_xsave_all_areas(X86CPU *cpu, void *buf, uint32_t buflen)
memcpy(pkru, &env->pkru, sizeof(env->pkru));
}
+
+ e = &x86_ext_save_areas[XSTATE_XTILE_CFG_BIT];
+ if (e->size && e->offset) {
+ XSaveXTILECFG *tilecfg = buf + e->offset;
+
+ memcpy(tilecfg, &env->xtilecfg, sizeof(env->xtilecfg));
+ }
+
+ e = &x86_ext_save_areas[XSTATE_XTILE_DATA_BIT];
+ if (e->size && e->offset && buflen >= e->size + e->offset) {
+ XSaveXTILEDATA *tiledata = buf + e->offset;
+
+ memcpy(tiledata, &env->xtiledata, sizeof(env->xtiledata));
+ }
#endif
}
@@ -247,5 +261,19 @@ void x86_cpu_xrstor_all_areas(X86CPU *cpu, const void *buf, uint32_t buflen)
pkru = buf + e->offset;
memcpy(&env->pkru, pkru, sizeof(env->pkru));
}
+
+ e = &x86_ext_save_areas[XSTATE_XTILE_CFG_BIT];
+ if (e->size && e->offset) {
+ const XSaveXTILECFG *tilecfg = buf + e->offset;
+
+ memcpy(&env->xtilecfg, tilecfg, sizeof(env->xtilecfg));
+ }
+
+ e = &x86_ext_save_areas[XSTATE_XTILE_DATA_BIT];
+ if (e->size && e->offset && buflen >= e->size + e->offset) {
+ const XSaveXTILEDATA *tiledata = buf + e->offset;
+
+ memcpy(&env->xtiledata, tiledata, sizeof(env->xtiledata));
+ }
#endif
}
--
2.35.3