{"id":2197733,"url":"http://patchwork.ozlabs.org/api/1.0/patches/2197733/?format=json","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/1.0/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20260218114233.266178-28-anisinha@redhat.com>","date":"2026-02-18T11:42:20","name":"[v5,27/34] kvm/xen-emu: re-initialize capabilities during confidential guest reset","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"b1b6b0269ab3f1d0687452b0c94e5fa90c229cf7","submitter":{"id":86030,"url":"http://patchwork.ozlabs.org/api/1.0/people/86030/?format=json","name":"Ani Sinha","email":"anisinha@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260218114233.266178-28-anisinha@redhat.com/mbox/","series":[{"id":492541,"url":"http://patchwork.ozlabs.org/api/1.0/series/492541/?format=json","date":"2026-02-18T11:41:56","name":"Introduce support for confidential guest reset (x86)","version":5,"mbox":"http://patchwork.ozlabs.org/series/492541/mbox/"}],"check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2197733/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=Vv6AQx+7;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=google header.b=t7bPE/Pt;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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Xen capabilities needs to be re-initialized in\nKVM against the new file descriptor.\n\nSigned-off-by: Ani Sinha \n---\n target/i386/kvm/xen-emu.c | 50 +++++++++++++++++++++++++++++++++++++--\n 1 file changed, 48 insertions(+), 2 deletions(-)","diff":"diff --git a/target/i386/kvm/xen-emu.c b/target/i386/kvm/xen-emu.c\nindex 52de019834..69527145eb 100644\n--- a/target/i386/kvm/xen-emu.c\n+++ b/target/i386/kvm/xen-emu.c\n@@ -44,9 +44,12 @@\n \n #include \"xen-compat.h\"\n \n+NotifierWithReturn xen_vmfd_change_notifier;\n+static bool hyperv_enabled;\n static void xen_vcpu_singleshot_timer_event(void *opaque);\n static void xen_vcpu_periodic_timer_event(void *opaque);\n static int vcpuop_stop_singleshot_timer(CPUState *cs);\n+static int do_initialize_xen_caps(KVMState *s, uint32_t hypercall_msr);\n \n #ifdef TARGET_X86_64\n #define hypercall_compat32(longmode) (!(longmode))\n@@ -54,6 +57,30 @@ static int vcpuop_stop_singleshot_timer(CPUState *cs);\n #define hypercall_compat32(longmode) (false)\n #endif\n \n+static int xen_handle_vmfd_change(NotifierWithReturn *n,\n+ void *data, Error** errp)\n+{\n+ int ret;\n+\n+ /* we are not interested in pre vmfd change notification */\n+ if (((VmfdChangeNotifier *)data)->pre) {\n+ return 0;\n+ }\n+\n+ ret = do_initialize_xen_caps(kvm_state, XEN_HYPERCALL_MSR);\n+ if (ret < 0) {\n+ return ret;\n+ }\n+\n+ if (hyperv_enabled) {\n+ ret = do_initialize_xen_caps(kvm_state, XEN_HYPERCALL_MSR_HYPERV);\n+ if (ret < 0) {\n+ return ret;\n+ }\n+ }\n+ return 0;\n+}\n+\n static bool kvm_gva_to_gpa(CPUState *cs, uint64_t gva, uint64_t *gpa,\n size_t *len, bool is_write)\n {\n@@ -111,15 +138,16 @@ static inline int kvm_copy_to_gva(CPUState *cs, uint64_t gva, void *buf,\n return kvm_gva_rw(cs, gva, buf, sz, true);\n }\n \n-int kvm_xen_init(KVMState *s, uint32_t hypercall_msr)\n+static int do_initialize_xen_caps(KVMState *s, uint32_t hypercall_msr)\n {\n+ int xen_caps, ret;\n const int required_caps = KVM_XEN_HVM_CONFIG_HYPERCALL_MSR |\n KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL | KVM_XEN_HVM_CONFIG_SHARED_INFO;\n+\n struct kvm_xen_hvm_config cfg = {\n .msr = hypercall_msr,\n .flags = KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL,\n };\n- int xen_caps, ret;\n \n xen_caps = kvm_check_extension(s, KVM_CAP_XEN_HVM);\n if (required_caps & ~xen_caps) {\n@@ -143,6 +171,21 @@ int kvm_xen_init(KVMState *s, uint32_t hypercall_msr)\n strerror(-ret));\n return ret;\n }\n+ return xen_caps;\n+}\n+\n+int kvm_xen_init(KVMState *s, uint32_t hypercall_msr)\n+{\n+ int xen_caps;\n+\n+ xen_caps = do_initialize_xen_caps(s, hypercall_msr);\n+ if (xen_caps < 0) {\n+ return xen_caps;\n+ }\n+\n+ if (!hyperv_enabled && (hypercall_msr == XEN_HYPERCALL_MSR_HYPERV)) {\n+ hyperv_enabled = true;\n+ }\n \n /* If called a second time, don't repeat the rest of the setup. */\n if (s->xen_caps) {\n@@ -185,6 +228,9 @@ int kvm_xen_init(KVMState *s, uint32_t hypercall_msr)\n xen_primary_console_reset();\n xen_xenstore_reset();\n \n+ xen_vmfd_change_notifier.notify = xen_handle_vmfd_change;\n+ kvm_vmfd_add_change_notifier(&xen_vmfd_change_notifier);\n+\n return 0;\n }\n \n","prefixes":["v5","27/34"]}