From: David Woodhouse <dwmw2@infradead.org>
To: qemu-devel@nongnu.org
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
"Paul Durrant" <paul@xen.org>,
"Joao Martins" <joao.m.martins@oracle.com>,
"Ankur Arora" <ankur.a.arora@oracle.com>,
"Philippe Mathieu-Daudé" <philmd@linaro.org>,
"Thomas Huth" <thuth@redhat.com>,
"Alex Bennée" <alex.bennee@linaro.org>,
"Juan Quintela" <quintela@redhat.com>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
"Claudio Fontana" <cfontana@suse.de>,
"Julien Grall" <julien@xen.org>
Subject: [RFC PATCH v5 21/52] i386/xen: handle VCPUOP_register_vcpu_info
Date: Fri, 30 Dec 2022 12:12:04 +0000 [thread overview]
Message-ID: <20221230121235.1282915-22-dwmw2@infradead.org> (raw)
In-Reply-To: <20221230121235.1282915-1-dwmw2@infradead.org>
From: Joao Martins <joao.m.martins@oracle.com>
Handle the hypercall to set a per vcpu info, and also wire up the default
vcpu_info in the shared_info page for the first 32 vCPUs.
To avoid deadlock within KVM a vCPU thread must set its *own* vcpu_info
rather than it being set from the context in which the hypercall is
invoked.
Add the vcpu_info (and default) GPA to the vmstate_x86_cpu for migration,
and restore it in kvm_arch_put_registers() appropriately.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
---
target/i386/cpu.h | 2 +
target/i386/kvm/kvm.c | 17 ++++
target/i386/kvm/trace-events | 1 +
target/i386/kvm/xen-emu.c | 152 ++++++++++++++++++++++++++++++++++-
target/i386/kvm/xen-emu.h | 2 +
target/i386/machine.c | 19 +++++
6 files changed, 190 insertions(+), 3 deletions(-)
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index c6c57baed5..109b2e5669 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1788,6 +1788,8 @@ typedef struct CPUArchState {
#endif
#if defined(CONFIG_KVM)
struct kvm_nested_state *nested_state;
+ uint64_t xen_vcpu_info_gpa;
+ uint64_t xen_vcpu_info_default_gpa;
#endif
#if defined(CONFIG_HVF)
HVFX86LazyFlags hvf_lflags;
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index f365e56fcc..52d69e87e7 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -4734,6 +4734,15 @@ int kvm_arch_put_registers(CPUState *cpu, int level)
kvm_arch_set_tsc_khz(cpu);
}
+#ifdef CONFIG_XEN_EMU
+ if (xen_mode == XEN_EMULATE && level == KVM_PUT_FULL_STATE) {
+ ret = kvm_put_xen_state(cpu);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+#endif
+
ret = kvm_getput_regs(x86_cpu, 1);
if (ret < 0) {
return ret;
@@ -4833,6 +4842,14 @@ int kvm_arch_get_registers(CPUState *cs)
if (ret < 0) {
goto out;
}
+#ifdef CONFIG_XEN_EMU
+ if (xen_mode == XEN_EMULATE) {
+ ret = kvm_get_xen_state(cs);
+ if (ret < 0) {
+ goto out;
+ }
+ }
+#endif
ret = 0;
out:
cpu_sync_bndcs_hflags(&cpu->env);
diff --git a/target/i386/kvm/trace-events b/target/i386/kvm/trace-events
index 0a47c26e80..14e54dfca5 100644
--- a/target/i386/kvm/trace-events
+++ b/target/i386/kvm/trace-events
@@ -9,3 +9,4 @@ kvm_x86_update_msi_routes(int num) "Updated %d MSI routes"
# xen-emu.c
kvm_xen_hypercall(int cpu, uint8_t cpl, uint64_t input, uint64_t a0, uint64_t a1, uint64_t a2, uint64_t ret) "xen_hypercall: cpu %d cpl %d input %" PRIu64 " a0 0x%" PRIx64 " a1 0x%" PRIx64 " a2 0x%" PRIx64" ret 0x%" PRIx64
kvm_xen_set_shared_info(uint64_t gfn) "shared info at gfn 0x%" PRIx64
+kvm_xen_set_vcpu_attr(int cpu, int type, uint64_t gpa) "vcpu attr cpu %d type %d gpa 0x%" PRIx64
diff --git a/target/i386/kvm/xen-emu.c b/target/i386/kvm/xen-emu.c
index 0e9ae481d8..aa06588c07 100644
--- a/target/i386/kvm/xen-emu.c
+++ b/target/i386/kvm/xen-emu.c
@@ -120,6 +120,8 @@ int kvm_xen_init(KVMState *s, uint32_t hypercall_msr)
int kvm_xen_init_vcpu(CPUState *cs)
{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
int err;
/*
@@ -143,6 +145,9 @@ int kvm_xen_init_vcpu(CPUState *cs)
}
}
+ env->xen_vcpu_info_gpa = INVALID_GPA;
+ env->xen_vcpu_info_default_gpa = INVALID_GPA;
+
return 0;
}
@@ -188,10 +193,58 @@ static bool kvm_xen_hcall_xen_version(struct kvm_xen_exit *exit, X86CPU *cpu,
return true;
}
+static int kvm_xen_set_vcpu_attr(CPUState *cs, uint16_t type, uint64_t gpa)
+{
+ struct kvm_xen_vcpu_attr xhsi;
+
+ xhsi.type = type;
+ xhsi.u.gpa = gpa;
+
+ trace_kvm_xen_set_vcpu_attr(cs->cpu_index, type, gpa);
+
+ return kvm_vcpu_ioctl(cs, KVM_XEN_VCPU_SET_ATTR, &xhsi);
+}
+
+static void do_set_vcpu_info_default_gpa(CPUState *cs, run_on_cpu_data data)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+
+ env->xen_vcpu_info_default_gpa = data.host_ulong;
+
+ /* Changing the default does nothing if a vcpu_info was explicitly set. */
+ if (env->xen_vcpu_info_gpa == INVALID_GPA) {
+ kvm_xen_set_vcpu_attr(cs, KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO,
+ env->xen_vcpu_info_default_gpa);
+ }
+}
+
+static void do_set_vcpu_info_gpa(CPUState *cs, run_on_cpu_data data)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+
+ env->xen_vcpu_info_gpa = data.host_ulong;
+
+ kvm_xen_set_vcpu_attr(cs, KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO,
+ env->xen_vcpu_info_gpa);
+}
+
+static void do_vcpu_soft_reset(CPUState *cs, run_on_cpu_data data)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+
+ env->xen_vcpu_info_gpa = INVALID_GPA;
+ env->xen_vcpu_info_default_gpa = INVALID_GPA;
+
+ kvm_xen_set_vcpu_attr(cs, KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO, INVALID_GPA);
+}
+
static int xen_set_shared_info(uint64_t gfn)
{
uint64_t gpa = gfn << TARGET_PAGE_BITS;
- int err;
+ int i, err;
/*
* The xen_overlay device tells KVM about it too, since it had to
@@ -206,6 +259,15 @@ static int xen_set_shared_info(uint64_t gfn)
trace_kvm_xen_set_shared_info(gfn);
+ for (i = 0; i < XEN_LEGACY_MAX_VCPUS; i++) {
+ CPUState *cpu = qemu_get_cpu(i);
+ if (cpu) {
+ async_run_on_cpu(cpu, do_set_vcpu_info_default_gpa,
+ RUN_ON_CPU_HOST_ULONG(gpa));
+ }
+ gpa += sizeof(vcpu_info_t);
+ }
+
return err;
}
@@ -363,15 +425,43 @@ static bool kvm_xen_hcall_hvm_op(struct kvm_xen_exit *exit, X86CPU *cpu,
}
}
+static int vcpuop_register_vcpu_info(CPUState *cs, CPUState *target,
+ uint64_t arg)
+{
+ struct vcpu_register_vcpu_info rvi;
+ uint64_t gpa;
+
+ /* No need for 32/64 compat handling */
+ qemu_build_assert(sizeof(rvi) == 16);
+ qemu_build_assert(sizeof(struct vcpu_info) == 64);
+
+ if (!target) {
+ return -ENOENT;
+ }
+
+ if (kvm_copy_from_gva(cs, arg, &rvi, sizeof(rvi))) {
+ return -EFAULT;
+ }
+
+ if (rvi.offset > TARGET_PAGE_SIZE - sizeof(struct vcpu_info)) {
+ return -EINVAL;
+ }
+
+ gpa = ((rvi.mfn << TARGET_PAGE_BITS) + rvi.offset);
+ async_run_on_cpu(target, do_set_vcpu_info_gpa, RUN_ON_CPU_HOST_ULONG(gpa));
+ return 0;
+}
+
static bool kvm_xen_hcall_vcpu_op(struct kvm_xen_exit *exit, X86CPU *cpu,
int cmd, int vcpu_id, uint64_t arg)
{
+ CPUState *dest = qemu_get_cpu(vcpu_id);
+ CPUState *cs = CPU(cpu);
int err;
switch (cmd) {
case VCPUOP_register_vcpu_info:
- /* no vcpu info placement for now */
- err = -ENOSYS;
+ err = vcpuop_register_vcpu_info(cs, dest, arg);
break;
default:
@@ -384,8 +474,13 @@ static bool kvm_xen_hcall_vcpu_op(struct kvm_xen_exit *exit, X86CPU *cpu,
static int kvm_xen_soft_reset(void)
{
+ CPUState *cpu;
int err;
+ CPU_FOREACH(cpu) {
+ async_run_on_cpu(cpu, do_vcpu_soft_reset, RUN_ON_CPU_NULL);
+ }
+
err = xen_overlay_map_shinfo_page(INVALID_GFN);
if (err) {
return err;
@@ -531,3 +626,54 @@ int kvm_xen_handle_exit(X86CPU *cpu, struct kvm_xen_exit *exit)
exit->u.hcall.result);
return 0;
}
+
+int kvm_put_xen_state(CPUState *cs)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+ uint64_t gpa;
+ int ret;
+
+ gpa = env->xen_vcpu_info_gpa;
+ if (gpa == INVALID_GPA) {
+ gpa = env->xen_vcpu_info_default_gpa;
+ }
+
+ if (gpa != INVALID_GPA) {
+ ret = kvm_xen_set_vcpu_attr(cs, KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO, gpa);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+int kvm_get_xen_state(CPUState *cs)
+{
+ X86CPU *cpu = X86_CPU(cs);
+ CPUX86State *env = &cpu->env;
+ uint64_t gpa;
+
+ /*
+ * The kernel does not mark vcpu_info as dirty when it delivers interrupts
+ * to it. It's up to userspace to *assume* that any page shared thus is
+ * always considered dirty. The shared_info page is different since it's
+ * an overlay and migrated separately anyway.
+ */
+ gpa = env->xen_vcpu_info_gpa;
+ if (gpa == INVALID_GPA) {
+ gpa = env->xen_vcpu_info_default_gpa;
+ }
+ if (gpa != INVALID_GPA) {
+ MemoryRegionSection mrs = memory_region_find(get_system_memory(),
+ gpa,
+ sizeof(struct vcpu_info));
+ if (mrs.mr && mrs.size >= sizeof(struct vcpu_info)) {
+ memory_region_set_dirty(mrs.mr, mrs.offset_within_region,
+ sizeof(struct vcpu_info));
+ }
+ }
+
+ return 0;
+}
diff --git a/target/i386/kvm/xen-emu.h b/target/i386/kvm/xen-emu.h
index 21faf6bf38..452605699a 100644
--- a/target/i386/kvm/xen-emu.h
+++ b/target/i386/kvm/xen-emu.h
@@ -26,5 +26,7 @@
int kvm_xen_init(KVMState *s, uint32_t hypercall_msr);
int kvm_xen_init_vcpu(CPUState *cs);
int kvm_xen_handle_exit(X86CPU *cpu, struct kvm_xen_exit *exit);
+int kvm_put_xen_state(CPUState *cs);
+int kvm_get_xen_state(CPUState *cs);
#endif /* QEMU_I386_KVM_XEN_EMU_H */
diff --git a/target/i386/machine.c b/target/i386/machine.c
index 310b125235..1215e616c8 100644
--- a/target/i386/machine.c
+++ b/target/i386/machine.c
@@ -6,8 +6,10 @@
#include "kvm/hyperv.h"
#include "hw/i386/x86.h"
#include "kvm/kvm_i386.h"
+#include "hw/xen/xen.h"
#include "sysemu/kvm.h"
+#include "sysemu/kvm_xen.h"
#include "sysemu/tcg.h"
#include "qemu/error-report.h"
@@ -1257,6 +1259,22 @@ static const VMStateDescription vmstate_nested_state = {
}
};
+static bool xen_vcpu_needed(void *opaque)
+{
+ return (xen_mode == XEN_EMULATE);
+}
+
+static const VMStateDescription vmstate_xen_vcpu = {
+ .name = "cpu/xen_vcpu",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .needed = xen_vcpu_needed,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT64(env.xen_vcpu_info_gpa, X86CPU),
+ VMSTATE_UINT64(env.xen_vcpu_info_default_gpa, X86CPU),
+ VMSTATE_END_OF_LIST()
+ }
+};
#endif
static bool mcg_ext_ctl_needed(void *opaque)
@@ -1716,6 +1734,7 @@ const VMStateDescription vmstate_x86_cpu = {
#endif
#ifdef CONFIG_KVM
&vmstate_nested_state,
+ &vmstate_xen_vcpu,
#endif
&vmstate_msr_tsx_ctrl,
&vmstate_msr_intel_sgx,
--
2.35.3
next prev parent reply other threads:[~2022-12-30 12:28 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-30 12:11 [RFC PATCH v5 00/52] Xen support under KVM David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 01/52] include: import Xen public headers to include/standard-headers/ David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 02/52] xen: add CONFIG_XENFV_MACHINE and CONFIG_XEN_EMU options for Xen emulation David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 03/52] xen: Add XEN_DISABLED mode and make it default David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 04/52] i386/kvm: Add xen-version KVM accelerator property and init KVM Xen support David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 05/52] i386/kvm: handle Xen HVM cpuid leaves David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 06/52] i386/hvm: Set Xen vCPU ID in KVM David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 07/52] xen-platform: exclude vfio-pci from the PCI platform unplug David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 08/52] xen-platform: allow its creation with XEN_EMULATE mode David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 09/52] hw/xen_backend: refactor xen_be_init() David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 10/52] i386/xen: handle guest hypercalls David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 11/52] i386/xen: implement HYPERVISOR_xen_version David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 12/52] i386/xen: implement HYPERVISOR_sched_op, SCHEDOP_shutdown David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 13/52] i386/xen: Implement SCHEDOP_poll and SCHEDOP_yield David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 14/52] hw/xen: Add xen_overlay device for emulating shared xenheap pages David Woodhouse
2023-01-03 17:54 ` Dr. David Alan Gilbert
2022-12-30 12:11 ` [RFC PATCH v5 15/52] i386/xen: add pc_machine_kvm_type to initialize XEN_EMULATE mode David Woodhouse
2022-12-30 12:11 ` [RFC PATCH v5 16/52] i386/xen: manage and save/restore Xen guest long_mode setting David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 17/52] i386/xen: implement HYPERVISOR_memory_op David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 18/52] i386/xen: implement XENMEM_add_to_physmap_batch David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 19/52] i386/xen: implement HYPERVISOR_hvm_op David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 20/52] i386/xen: implement HYPERVISOR_vcpu_op David Woodhouse
2022-12-30 12:12 ` David Woodhouse [this message]
2023-01-03 18:13 ` [RFC PATCH v5 21/52] i386/xen: handle VCPUOP_register_vcpu_info Dr. David Alan Gilbert
2022-12-30 12:12 ` [RFC PATCH v5 22/52] i386/xen: handle VCPUOP_register_vcpu_time_info David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 23/52] i386/xen: handle VCPUOP_register_runstate_memory_area David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 24/52] i386/xen: implement HYPERVISOR_event_channel_op David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 25/52] i386/xen: implement HVMOP_set_evtchn_upcall_vector David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 26/52] i386/xen: implement HVMOP_set_param David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 27/52] hw/xen: Add xen_evtchn device for event channel emulation David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 28/52] i386/xen: Add support for Xen event channel delivery to vCPU David Woodhouse
2023-01-09 21:18 ` David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 29/52] hw/xen: Implement EVTCHNOP_status David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 30/52] hw/xen: Implement EVTCHNOP_close David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 31/52] hw/xen: Implement EVTCHNOP_unmask David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 32/52] hw/xen: Implement EVTCHNOP_bind_virq David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 33/52] hw/xen: Implement EVTCHNOP_bind_ipi David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 34/52] hw/xen: Implement EVTCHNOP_send David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 35/52] hw/xen: Implement EVTCHNOP_alloc_unbound David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 36/52] hw/xen: Implement EVTCHNOP_bind_interdomain David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 37/52] hw/xen: Implement EVTCHNOP_bind_vcpu David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 38/52] hw/xen: Implement EVTCHNOP_reset David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 39/52] i386/xen: add monitor commands to test event injection David Woodhouse
2023-01-04 12:48 ` Dr. David Alan Gilbert
2023-01-05 19:42 ` David Woodhouse
2023-01-05 20:09 ` Dr. David Alan Gilbert
2023-01-09 17:24 ` David Woodhouse
2023-01-09 18:51 ` Dr. David Alan Gilbert
2023-01-09 19:49 ` David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 40/52] hw/xen: Support HVM_PARAM_CALLBACK_TYPE_GSI callback David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 41/52] hw/xen: Support HVM_PARAM_CALLBACK_TYPE_PCI_INTX callback David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 42/52] kvm/i386: Add xen-gnttab-max-frames property David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 43/52] hw/xen: Add xen_gnttab device for grant table emulation David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 44/52] hw/xen: Support mapping grant frames David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 45/52] i386/xen: Implement HYPERVISOR_grant_table_op and GNTTABOP_[gs]et_verson David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 46/52] hw/xen: Implement GNTTABOP_query_size David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 47/52] i386/xen: handle PV timer hypercalls David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 48/52] i386/xen: Reserve Xen special pages for console, xenstore rings David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 49/52] i386/xen: handle HVMOP_get_param David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 50/52] hw/xen: Add backend implementation of interdomain event channel support David Woodhouse
2023-01-04 11:22 ` Dr. David Alan Gilbert
2023-01-04 14:33 ` David Woodhouse
2023-01-04 11:52 ` Dr. David Alan Gilbert
2022-12-30 12:12 ` [RFC PATCH v5 51/52] hw/xen: Add xen_xenstore device for xenstore emulation David Woodhouse
2023-01-04 12:01 ` Dr. David Alan Gilbert
2023-01-04 14:35 ` David Woodhouse
2022-12-30 12:12 ` [RFC PATCH v5 52/52] hw/xen: Add basic ring handling to xenstore David Woodhouse
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