From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-189.mta1.migadu.com (out-189.mta1.migadu.com [95.215.58.189]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6907B1C84BC for ; Wed, 8 Jul 2026 06:13:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.189 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783491183; cv=none; b=rHLUIbkl1EEFInC8S8hClP5mU0tzhcFhP86ih/265FwglNnZLoJpxLnWeW406Lh36/H4ASZ+33rwtbnUJFgDYARJEWjRPBzG2JbbH4RfjAirOKNO6mcYHToSuRhwxfXhdjkBEfHddk9ngJ3ftv/4BOqlxM4He0tXaRyivihKU2c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783491183; c=relaxed/simple; bh=lPGsvclOAgh0V32F20ZSyGCdcW75sOUIIViF4fpQO2I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GK3kZGMuPZ3HX2vup9xdL3BmLEUk2HD6RNdlKyF70sG3lhHkAphWxmghb9kZjsMLVBzMRia59bsQ13sZst+FN3DAHyKFqbGM7bkNeevR/G2an7ZsHJ5p9kDJ2XPICnQjkiGCusOpZVXkm+30O5FqK5GynIAxPlfRr8qt7ic8A4M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=PvBoRSaP; arc=none smtp.client-ip=95.215.58.189 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="PvBoRSaP" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1783491180; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nbhZAdbxxI1/a4pn8N1gZliVnKCnUpBEdqiligF4ubY=; b=PvBoRSaPlwNC1Irbwu+t3S/2h21PyxY1OqwMISIaIr1BLYNNCyFTyePO+mnWRnFBwkylbA 2Xw5rg1ywvVnBingBeib0YyN1YPAXW9J6zjEN9sclrHN1JjAfYbYnCeZF74gBoWMLV8ymR VihuFyV92MesDiw2KLTZpOlj299N3uY= From: Tao Cui To: qemu-devel@nongnu.org Cc: pbonzini@redhat.com, armbru@redhat.com, eblake@redhat.com, kvm@vger.kernel.org, Tao Cui Subject: [PATCH v1 2/2] accel/kvm: emit KVM_VCPU_ERROR on unrecoverable vCPU exits Date: Wed, 8 Jul 2026 14:12:20 +0800 Message-ID: <20260708061220.53507-3-cui.tao@linux.dev> In-Reply-To: <20260708061220.53507-1-cui.tao@linux.dev> References: <20260708061220.53507-1-cui.tao@linux.dev> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: Tao Cui Emit the KVM_VCPU_ERROR event at the three points where a vCPU run becomes unrecoverable: - KVM_RUN ioctl failure (reason "ioctl-failed") - KVM_EXIT_UNKNOWN (reason "unknown") - KVM_EXIT_INTERNAL_ERROR (reason "internal-error", with suberror and exit-data) The KVM_RUN loop in kvm_cpu_exec() runs without the BQL, but QMP event emission goes through the monitor and requires it; take and release the lock around the send, mirroring the KVM_SYSTEM_EVENT_CRASH path. This resolves the long-standing FIXME in kvm_handle_internal_error(). Signed-off-by: Tao Cui --- accel/kvm/kvm-all.c | 46 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 43 insertions(+), 3 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 5d55cb45cf..4f68e3b82b 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -46,6 +46,7 @@ #include "qapi/visitor.h" #include "qapi/qapi-types-common.h" #include "qapi/qapi-visit-common.h" +#include "qapi/qapi-events-run-state.h" #include "system/reset.h" #include "qemu/guest-random.h" #include "system/hw_accel.h" @@ -3140,6 +3141,38 @@ static void kvm_handle_io(uint16_t port, MemTxAttrs attrs, void *data, int direc } } +/* + * Notify the management layer that a vCPU hit an unrecoverable KVM run + * error. The KVM_RUN loop in kvm_cpu_exec() runs without the BQL, but + * emitting a QMP event goes through the monitor and therefore requires + * it; take/release the lock around the send. + */ +static void kvm_emit_vcpu_error(CPUState *cpu, KvmVcpuErrorReason reason, + bool has_suberror, int64_t suberror, + uint32_t ndata, const uint64_t *data) +{ + g_autofree char *qom_path = object_get_canonical_path(OBJECT(cpu)); + uint64List *exit_data = NULL; + uint64List **tail = &exit_data; + uint32_t i; + + for (i = 0; i < ndata; i++) { + uint64List *node = g_new(uint64List, 1); + node->value = data[i]; + node->next = NULL; + *tail = node; + tail = &node->next; + } + + bql_lock(); + qapi_event_send_kvm_vcpu_error(cpu->cpu_index, qom_path, reason, + has_suberror, suberror, + !!ndata, exit_data); + bql_unlock(); + + qapi_free_uint64List(exit_data); +} + static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run) { int i; @@ -3151,6 +3184,12 @@ static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run) fprintf(stderr, "extra data[%d]: 0x%016"PRIx64"\n", i, (uint64_t)run->internal.data[i]); } + + kvm_emit_vcpu_error(cpu, KVM_VCPU_ERROR_REASON_INTERNAL_ERROR, + true, run->internal.suberror, + run->internal.ndata, + (const uint64_t *)run->internal.data); + if (run->internal.suberror == KVM_INTERNAL_ERROR_EMULATION) { fprintf(stderr, "emulation failure\n"); if (!kvm_arch_stop_on_emulation_error(cpu)) { @@ -3158,9 +3197,6 @@ static int kvm_handle_internal_error(CPUState *cpu, struct kvm_run *run) return EXCP_INTERRUPT; } } - /* FIXME: Should trigger a qmp message to let management know - * something went wrong. - */ return -1; } @@ -3508,6 +3544,8 @@ int kvm_cpu_exec(CPUState *cpu) "secondary threads offline.\n"); } #endif + kvm_emit_vcpu_error(cpu, KVM_VCPU_ERROR_REASON_IOCTL_FAILED, + false, 0, 0, NULL); ret = -1; break; } @@ -3543,6 +3581,8 @@ int kvm_cpu_exec(CPUState *cpu) case KVM_EXIT_UNKNOWN: fprintf(stderr, "KVM: unknown exit, hardware reason %" PRIx64 "\n", (uint64_t)run->hw.hardware_exit_reason); + kvm_emit_vcpu_error(cpu, KVM_VCPU_ERROR_REASON_UNKNOWN, + false, 0, 0, NULL); ret = -1; break; case KVM_EXIT_INTERNAL_ERROR: -- 2.43.0