From patchwork Thu Nov 21 15:42:17 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 13882110 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 415BED78782 for ; Thu, 21 Nov 2024 15:44:43 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tE9M0-0002fd-2i; Thu, 21 Nov 2024 10:44:24 -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 1tE9Lx-0002bP-5V for qemu-devel@nongnu.org; Thu, 21 Nov 2024 10:44:21 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tE9Lv-00015c-K7 for qemu-devel@nongnu.org; Thu, 21 Nov 2024 10:44:20 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1732203858; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=0txKiQWpxyguRebXD1DZVJACnLLYk3HWNLZCDAk2wrg=; b=XQY6tPxmR8ZFU+UIssbHFCdscqDtdX6lf3jfXVgcmNuPvzgiYTOaSRdByFwIX0Qjhl9fDO RQXAkahULljFMQhTv8ZfiMPRksB9inR5dKVGGWtE+2gG0Ohw/CySAGg+NbnrW/MRaeNavx qwVWh+l4cL/zQIPfGMEJASIKXNGsO0o= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-584-PTtEFarwO6e5dqT1A9266Q-1; Thu, 21 Nov 2024 10:44:15 -0500 X-MC-Unique: PTtEFarwO6e5dqT1A9266Q-1 X-Mimecast-MFC-AGG-ID: PTtEFarwO6e5dqT1A9266Q Received: from mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.15]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 20B7C1956095; Thu, 21 Nov 2024 15:44:14 +0000 (UTC) Received: from toolbox.redhat.com (unknown [10.42.28.5]) by mx-prod-int-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id C68191956086; Thu, 21 Nov 2024 15:44:07 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Thomas Huth , Ani Sinha , =?utf-8?q?Alex_Benn=C3=A9e?= , Peter Maydell , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= Subject: [PATCH v2 17/18] tests/functional: add a QMP backdoor for debugging stalled tests Date: Thu, 21 Nov 2024 15:42:17 +0000 Message-ID: <20241121154218.1423005-18-berrange@redhat.com> In-Reply-To: <20241121154218.1423005-1-berrange@redhat.com> References: <20241121154218.1423005-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.15 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.14, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Support the QEMU_TEST_QMP_BACKDOOR=backdoor.sock env variable as a way to get a QMP backdoor for debugging a stalled QEMU test. Most typically this would be used if running the tests directly: $ QEMU_TEST_QMP_BACKDOOR=backdoor.sock \ QEMU_TEST_QEMU_BINARY=./build/qemu-system-arm \ PYTHONPATH=./python \ ./tests/functional/test_arm_tuxrun.py And then, when the test stalls, in a second shell run: $ ./scripts/qmp/qmp-shell backdoor.sock Signed-off-by: Daniel P. Berrangé --- docs/devel/testing/functional.rst | 10 ++++++++++ tests/functional/qemu_test/testcase.py | 7 +++++++ 2 files changed, 17 insertions(+) diff --git a/docs/devel/testing/functional.rst b/docs/devel/testing/functional.rst index 6b5d0c5b98..b8ad7b0bf7 100644 --- a/docs/devel/testing/functional.rst +++ b/docs/devel/testing/functional.rst @@ -176,6 +176,16 @@ primarily depend on the value of the ``qemu_bin`` class attribute. If it is not explicitly set by the test code, its default value will be the result the QEMU_TEST_QEMU_BINARY environment variable. +Debugging hung QEMU +^^^^^^^^^^^^^^^^^^^ + +When test cases go wrong it may be helpful to debug a stalled QEMU +process. While the QEMUMachine class owns the primary QMP monitor +socket, it is possible to request a second QMP monitor be created +by setting the ``QEMU_TEST_QMP_BACKDOOR`` env variable to refer +to a UNIX socket name. The ``qmp-shell`` command can then be +attached to the stalled QEMU to examine its live state. + Attribute reference ------------------- diff --git a/tests/functional/qemu_test/testcase.py b/tests/functional/qemu_test/testcase.py index e2a329c3e5..fceafb32b0 100644 --- a/tests/functional/qemu_test/testcase.py +++ b/tests/functional/qemu_test/testcase.py @@ -175,6 +175,13 @@ def _new_vm(self, name, *args): log_dir=self.logdir) self.log.debug('QEMUMachine "%s" created', name) self.log.debug('QEMUMachine "%s" temp_dir: %s', name, vm.temp_dir) + + sockpath = os.environ.get("QEMU_TEST_QMP_BACKDOOR", None) + if sockpath is not None: + vm.add_args("-chardev", + f"socket,id=backdoor,path={sockpath},server=on,wait=off", + "-mon", "chardev=backdoor,mode=control") + if args: vm.add_args(*args) return vm