From mboxrd@z Thu Jan 1 00:00:00 1970 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 574D8C433EF for ; Mon, 24 Jan 2022 18:35:02 +0000 (UTC) Received: from localhost ([::1]:48558 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nC4BB-0004s0-8g for qemu-devel@archiver.kernel.org; Mon, 24 Jan 2022 13:35:01 -0500 Received: from eggs.gnu.org ([209.51.188.92]:38150) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nC3k7-0001qX-Qe for qemu-devel@nongnu.org; Mon, 24 Jan 2022 13:07:05 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:42912) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nC3k6-0006wn-4X for qemu-devel@nongnu.org; Mon, 24 Jan 2022 13:07:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643047621; 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=erCpUhOqiatPqnAj8F0/tsFcIpHI+GWpdKXMz01vZks=; b=WA5wy/3JWQulJuA78ZzIRMwf12+UpRCnZ/1z1iUmv6DukAMYcE0gHkBsQz9Vd0EzAuUZux EXWI9oxsyXBPN6wczb9Q/3Mcsz5LQXtins8iH3ir0UcvN3fZKEE8GLaHdvzhW0Xi30F8Iz Mc+kdQusCYup+jy92KtIfaUtuHAx2HE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-130-K_YQIYq0N9qWA9pqH2CZgQ-1; Mon, 24 Jan 2022 13:06:58 -0500 X-MC-Unique: K_YQIYq0N9qWA9pqH2CZgQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 2C24585EE70; Mon, 24 Jan 2022 18:06:57 +0000 (UTC) Received: from scv.redhat.com (unknown [10.22.35.175]) by smtp.corp.redhat.com (Postfix) with ESMTP id E9F2C798D3; Mon, 24 Jan 2022 18:06:50 +0000 (UTC) From: John Snow To: qemu-devel@nongnu.org Subject: [PATCH v3 2/4] python/machine: raise VMLaunchFailure exception from launch() Date: Mon, 24 Jan 2022 13:06:24 -0500 Message-Id: <20220124180626.627718-3-jsnow@redhat.com> In-Reply-To: <20220124180626.627718-1-jsnow@redhat.com> References: <20220124180626.627718-1-jsnow@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsnow@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=170.10.133.124; envelope-from=jsnow@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.158, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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: , Cc: Eduardo Habkost , Peter Maydell , Beraldo Leal , qemu-block@nongnu.org, Markus Armbruster , Hanna Reitz , Cleber Rosa , Kevin Wolf , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This allows us to pack in some extra information about the failure, which guarantees that if the caller did not *intentionally* cause a failure (by capturing this Exception), some pretty good clues will be printed at the bottom of the traceback information. This will help make failures in the event of a non-negative return code more obvious when they go unhandled; the current behavior is to print a warning message only in the event of signal-based terminations (for negative return codes). (Note: In Python, catching BaseException instead of Exception is like installing a signal handler that will run as long as Python itself doesn't crash. KeyboardInterrupt and several other "strong" events in Python are a BaseException. These events should generally not be suppressed, but occasionally we want to perform some cleanup in response to one.) Signed-off-by: John Snow --- python/qemu/machine/machine.py | 45 ++++++++++++++++++++--- tests/qemu-iotests/tests/mirror-top-perms | 3 +- 2 files changed, 40 insertions(+), 8 deletions(-) diff --git a/python/qemu/machine/machine.py b/python/qemu/machine/machine.py index 67ab06ca2b..a5972fab4d 100644 --- a/python/qemu/machine/machine.py +++ b/python/qemu/machine/machine.py @@ -74,6 +74,35 @@ class QEMUMachineAddDeviceError(QEMUMachineError): """ +class VMLaunchFailure(QEMUMachineError): + """ + Exception raised when a VM launch was attempted, but failed. + """ + def __init__(self, exitcode: Optional[int], + command: str, output: Optional[str]): + super().__init__(exitcode, command, output) + self.exitcode = exitcode + self.command = command + self.output = output + + def __str__(self) -> str: + ret = '' + if self.__cause__ is not None: + name = type(self.__cause__).__name__ + reason = str(self.__cause__) + if reason: + ret += f"{name}: {reason}" + else: + ret += f"{name}" + ret += '\n' + + if self.exitcode is not None: + ret += f"\tExit code: {self.exitcode}\n" + ret += f"\tCommand: {self.command}\n" + ret += f"\tOutput: {self.output}\n" + return ret + + class AbnormalShutdown(QEMUMachineError): """ Exception raised when a graceful shutdown was requested, but not performed. @@ -397,7 +426,7 @@ def launch(self) -> None: try: self._launch() - except: + except BaseException as exc: # We may have launched the process but it may # have exited before we could connect via QMP. # Assume the VM didn't launch or is exiting. @@ -408,11 +437,15 @@ def launch(self) -> None: else: self._post_shutdown() - LOG.debug('Error launching VM') - if self._qemu_full_args: - LOG.debug('Command: %r', ' '.join(self._qemu_full_args)) - if self._iolog: - LOG.debug('Output: %r', self._iolog) + if isinstance(exc, Exception): + raise VMLaunchFailure( + exitcode=self.exitcode(), + command=' '.join(self._qemu_full_args), + output=self._iolog + ) from exc + + # Don't wrap 'BaseException'; doing so would downgrade + # that exception. However, we still want to clean up. raise def _launch(self) -> None: diff --git a/tests/qemu-iotests/tests/mirror-top-perms b/tests/qemu-iotests/tests/mirror-top-perms index 0a51a613f3..b5849978c4 100755 --- a/tests/qemu-iotests/tests/mirror-top-perms +++ b/tests/qemu-iotests/tests/mirror-top-perms @@ -21,7 +21,6 @@ import os -from qemu.aqmp import ConnectError from qemu.machine import machine from qemu.qmp import QMPConnectError @@ -107,7 +106,7 @@ class TestMirrorTopPerms(iotests.QMPTestCase): self.vm_b.launch() print('ERROR: VM B launched successfully, ' 'this should not have happened') - except (QMPConnectError, ConnectError): + except (QMPConnectError, machine.VMLaunchFailure): assert 'Is another process using the image' in self.vm_b.get_log() result = self.vm.qmp('block-job-cancel', -- 2.31.1