From nobody Tue Feb 10 20:48:02 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 167115183320978.5880336878771; Thu, 15 Dec 2022 16:50:33 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1p5ypH-0007Un-L5; Thu, 15 Dec 2022 19:43:48 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5yny-0005a8-Qj for qemu-devel@nongnu.org; Thu, 15 Dec 2022 19:42:26 -0500 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1p5ynw-0006pJ-MD for qemu-devel@nongnu.org; Thu, 15 Dec 2022 19:42:26 -0500 Received: from i7.infradead.org ([2001:8b0:10b:1:21e:67ff:fecb:7a92]) by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1p5ymz-00Azyo-9M; Fri, 16 Dec 2022 00:42:13 +0000 Received: from dwoodhou by i7.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1p5ymw-003cOx-3Q; Fri, 16 Dec 2022 00:41:22 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=xNDBz0dz9aaRz4gtLDKk7jjwVAWCuOnXemhrtJukk0w=; b=n/cQvUIzRxWnWtxbvJPxrj7ffR T7+8qWAWJf5+58R2kqL6fEqIG2wiOOqfscijb8AwDlVLZSC2OwoTqdK8h/1RyO0D2nkB9ux/4fgic QYz7RS4GoMENNIIlQShXZljbzwYzML7MhQqzN7XtAunGGjJco2Bq9Yk6Hz9unBkNQ7qy6gEaNZYeZ PDM4XFsPOFXWftKHVSQSFNRMnA+VvZsVsubfTlxFLZVLorOJfayQb5XcAF+UdCkcdPPTRs7XHwdHn MkLgUeHrF3/qmfWJecx5f5J4pcV6+dZXl1MZpi4wlRjm3hue+M44qAoZMYTg0VYTwRZgDJyjnHczn oK9tV5wA==; From: David Woodhouse To: qemu-devel@nongnu.org Cc: Paolo Bonzini , Paul Durrant , Joao Martins , Ankur Arora , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Thomas Huth , =?UTF-8?q?Alex=20Benn=C3=A9e?= , Juan Quintela , "Dr . David Alan Gilbert" , Claudio Fontana Subject: [RFC PATCH v3 18/38] i386/xen: handle VCPUOP_register_vcpu_info Date: Fri, 16 Dec 2022 00:40:57 +0000 Message-Id: <20221216004117.862106-19-dwmw2@infradead.org> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20221216004117.862106-1-dwmw2@infradead.org> References: <20221216004117.862106-1-dwmw2@infradead.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SRS-Rewrite: SMTP reverse-path rewritten from by desiato.infradead.org. See http://www.infradead.org/rpr.html Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: none client-ip=2001:8b0:10b:1:d65d:64ff:fe57:4e05; envelope-from=BATV+54656a84ae694b50c6d0+7054+infradead.org+dwmw2@desiato.srs.infradead.org; helo=desiato.infradead.org X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1671151834599100003 Content-Type: text/plain; charset="utf-8" From: Joao Martins 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 Signed-off-by: David Woodhouse --- target/i386/cpu.h | 2 + target/i386/kvm/kvm.c | 19 +++++++++ target/i386/kvm/trace-events | 1 + target/i386/kvm/xen-emu.c | 78 ++++++++++++++++++++++++++++++++++-- target/i386/kvm/xen-emu.h | 1 + target/i386/machine.c | 21 ++++++++++ 6 files changed, 119 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 c37e44d88f..8affe1eeae 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -1802,6 +1802,9 @@ int kvm_arch_init_vcpu(CPUState *cs) has_msr_hv_hypercall =3D true; } =20 + env->xen_vcpu_info_gpa =3D UINT64_MAX; + env->xen_vcpu_info_default_gpa =3D UINT64_MAX; + if (cs->kvm_state->xen_version) { #ifdef CONFIG_XEN_EMU struct kvm_cpuid_entry2 *xen_max_leaf; @@ -4723,6 +4726,22 @@ int kvm_arch_put_registers(CPUState *cpu, int level) kvm_arch_set_tsc_khz(cpu); } =20 +#ifdef CONFIG_XEN_EMU + if (level =3D=3D KVM_PUT_FULL_STATE) { + uint64_t gpa =3D x86_cpu->env.xen_vcpu_info_gpa; + if (gpa =3D=3D UINT64_MAX) { + gpa =3D x86_cpu->env.xen_vcpu_info_default_gpa; + } + + if (gpa !=3D UINT64_MAX) { + ret =3D kvm_xen_set_vcpu_attr(cpu, KVM_XEN_VCPU_ATTR_TYPE_VCPU= _INFO, gpa); + if (ret < 0) { + return ret; + } + } + } +#endif + ret =3D kvm_getput_regs(x86_cpu, 1); if (ret < 0) { return ret; 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, uint6= 4_t a1, uint64_t a2, uint64_t ret) "xen_hypercall: cpu %d cpl %d input %" P= RIu64 " 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 t= ype %d gpa 0x%" PRIx64 diff --git a/target/i386/kvm/xen-emu.c b/target/i386/kvm/xen-emu.c index 83d98cbfd9..25c48248ce 100644 --- a/target/i386/kvm/xen-emu.c +++ b/target/i386/kvm/xen-emu.c @@ -147,10 +147,47 @@ static bool kvm_xen_hcall_xen_version(struct kvm_xen_= exit *exit, X86CPU *cpu, return true; } =20 +int kvm_xen_set_vcpu_attr(CPUState *cs, uint16_t type, uint64_t gpa) +{ + struct kvm_xen_vcpu_attr xhsi; + + xhsi.type =3D type; + xhsi.u.gpa =3D 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 dat= a) +{ + X86CPU *cpu =3D X86_CPU(cs); + CPUX86State *env =3D &cpu->env; + + env->xen_vcpu_info_default_gpa =3D data.host_ulong; + + /* Changing the default does nothing if a vcpu_info was explicitly set= . */ + if (env->xen_vcpu_info_gpa =3D=3D UINT64_MAX) { + 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 =3D X86_CPU(cs); + CPUX86State *env =3D &cpu->env; + + env->xen_vcpu_info_gpa =3D data.host_ulong; + + kvm_xen_set_vcpu_attr(cs, KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO, + env->xen_vcpu_info_gpa); +} + static int xen_set_shared_info(uint64_t gfn) { uint64_t gpa =3D gfn << TARGET_PAGE_BITS; - int err; + int i, err; =20 /* The xen_overlay device tells KVM about it too, since it had to * do that on migration load anyway (unless we're going to jump @@ -162,6 +199,14 @@ static int xen_set_shared_info(uint64_t gfn) =20 trace_kvm_xen_set_shared_info(gfn); =20 + for (i =3D 0; i < XEN_LEGACY_MAX_VCPUS; i++) { + CPUState *cpu =3D qemu_get_cpu(i); + if (cpu) { + async_run_on_cpu(cpu, do_set_vcpu_info_default_gpa, RUN_ON_CPU= _HOST_ULONG(gpa)); + } + gpa +=3D sizeof(vcpu_info_t); + } + return err; } =20 @@ -318,15 +363,42 @@ static bool kvm_xen_hcall_hvm_op(struct kvm_xen_exit = *exit, X86CPU *cpu, } } =20 +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) =3D=3D 16); + qemu_build_assert(sizeof(struct vcpu_info) =3D=3D 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 =3D ((rvi.mfn << TARGET_PAGE_BITS) + rvi.offset); + async_run_on_cpu(target, do_set_vcpu_info_gpa, RUN_ON_CPU_HOST_ULONG(g= pa)); + 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 =3D qemu_get_cpu(vcpu_id); + CPUState *cs =3D CPU(cpu); int err; =20 switch (cmd) { case VCPUOP_register_vcpu_info: - /* no vcpu info placement for now */ - err =3D -ENOSYS; + err =3D vcpuop_register_vcpu_info(cs, dest, arg); break; =20 default: diff --git a/target/i386/kvm/xen-emu.h b/target/i386/kvm/xen-emu.h index 76a3de6c4d..20da62d39f 100644 --- a/target/i386/kvm/xen-emu.h +++ b/target/i386/kvm/xen-emu.h @@ -25,5 +25,6 @@ =20 int kvm_xen_init(KVMState *s, uint32_t hypercall_msr); int kvm_xen_handle_exit(X86CPU *cpu, struct kvm_xen_exit *exit); +int kvm_xen_set_vcpu_attr(CPUState *cs, uint16_t type, uint64_t gpa); =20 #endif /* QEMU_I386_KVM_XEN_EMU_H */ diff --git a/target/i386/machine.c b/target/i386/machine.c index 310b125235..104cd6047c 100644 --- a/target/i386/machine.c +++ b/target/i386/machine.c @@ -1257,6 +1257,26 @@ static const VMStateDescription vmstate_nested_state= =3D { } }; =20 +static bool xen_vcpu_needed(void *opaque) +{ + X86CPU *cpu =3D opaque; + CPUX86State *env =3D &cpu->env; + + return (env->xen_vcpu_info_gpa !=3D UINT64_MAX || + env->xen_vcpu_info_default_gpa !=3D UINT64_MAX); +} + +static const VMStateDescription vmstate_xen_vcpu =3D { + .name =3D "cpu/xen_vcpu", + .version_id =3D 1, + .minimum_version_id =3D 1, + .needed =3D xen_vcpu_needed, + .fields =3D (VMStateField[]) { + VMSTATE_UINT64(env.xen_vcpu_info_gpa, X86CPU), + VMSTATE_UINT64(env.xen_vcpu_info_default_gpa, X86CPU), + VMSTATE_END_OF_LIST() + } +}; #endif =20 static bool mcg_ext_ctl_needed(void *opaque) @@ -1716,6 +1736,7 @@ const VMStateDescription vmstate_x86_cpu =3D { #endif #ifdef CONFIG_KVM &vmstate_nested_state, + &vmstate_xen_vcpu, #endif &vmstate_msr_tsx_ctrl, &vmstate_msr_intel_sgx, --=20 2.35.3