On Thu, 14 Feb 2019 18:11:28 +0100 David Hildenbrand <da...@redhat.com> wrote:
> The issue with testing asynchronous unplug requests it that they usually > require a running guest to handle the request. However, to test if > unplug of PCI devices works, we can apply a nice little trick on some > architectures: > > On system reset, x86 ACPI, s390x and spapr will perform the unplug, > resulting in the device of interest to get deleted and a DEVICE_DELETED > event getting sent. > > On s390x, we still get a warning > qemu-system-s390x: -device virtio-mouse-pci,id=dev0: > warning: Plugging a PCI/zPCI device without the 'zpci' CPU feature > enabled; the guest will not be able to see/use this device > > This will be fixed soon, when we enable the zpci CPU feature always > (Conny already has a patch for this queued). > > Cc: Collin Walling <wall...@linux.ibm.com> > Cc: Cornelia Huck <coh...@redhat.com> > Cc: Pierre Morel <pmo...@linux.ibm.com> > Cc: Michael S. Tsirkin <m...@redhat.com> > Cc: Marcel Apfelbaum <marcel.apfelb...@gmail.com> > Cc: David Gibson <da...@gibson.dropbear.id.au> > Cc: Greg Kurz <gr...@kaod.org> > Cc: Igor Mammedov <imamm...@redhat.com> > Cc: Eduardo Habkost <ehabk...@redhat.com> > Cc: Thomas Huth <th...@redhat.com> > Cc: Laurent Vivier <lviv...@redhat.com> > Cc: Paolo Bonzini <pbonz...@redhat.com> > Signed-off-by: David Hildenbrand <da...@redhat.com> > --- Nice trick indeed, but... > tests/Makefile.include | 4 ++ > tests/device_del-test.c | 103 ++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 107 insertions(+) > create mode 100644 tests/device_del-test.c > > diff --git a/tests/Makefile.include b/tests/Makefile.include > index b39e989f72..713e5e23a7 100644 > --- a/tests/Makefile.include > +++ b/tests/Makefile.include > @@ -192,6 +192,7 @@ check-qtest-i386-$(CONFIG_ISA_IPMI_KCS) += > tests/ipmi-kcs-test$(EXESUF) > # check-qtest-i386-$(CONFIG_ISA_IPMI_BT) += tests/ipmi-bt-test$(EXESUF) > check-qtest-i386-y += tests/i440fx-test$(EXESUF) > check-qtest-i386-y += tests/fw_cfg-test$(EXESUF) > +check-qtest-i386-y += tests/device_del-test$(EXESUF) > check-qtest-i386-y += tests/drive_del-test$(EXESUF) > check-qtest-i386-$(CONFIG_WDT_IB700) += tests/wdt_ib700-test$(EXESUF) > check-qtest-i386-y += tests/tco-test$(EXESUF) > @@ -256,6 +257,7 @@ check-qtest-ppc-$(CONFIG_M48T59) += > tests/m48t59-test$(EXESUF) > > check-qtest-ppc64-y += $(check-qtest-ppc-y) > check-qtest-ppc64-$(CONFIG_PSERIES) += tests/spapr-phb-test$(EXESUF) > +check-qtest-ppc64-$(CONFIG_PSERIES) += tests/device_del-test$(EXESUF) > check-qtest-ppc64-$(CONFIG_POWERNV) += tests/pnv-xscom-test$(EXESUF) > check-qtest-ppc64-y += tests/migration-test$(EXESUF) > check-qtest-ppc64-$(CONFIG_PSERIES) += tests/rtas-test$(EXESUF) > @@ -310,6 +312,7 @@ check-qtest-s390x-$(CONFIG_SLIRP) += > tests/test-netfilter$(EXESUF) > check-qtest-s390x-$(CONFIG_POSIX) += tests/test-filter-mirror$(EXESUF) > check-qtest-s390x-$(CONFIG_POSIX) += tests/test-filter-redirector$(EXESUF) > check-qtest-s390x-y += tests/drive_del-test$(EXESUF) > +check-qtest-s390x-y += tests/device_del-test$(EXESUF) > check-qtest-s390x-y += tests/virtio-ccw-test$(EXESUF) > check-qtest-s390x-y += tests/cpu-plug-test$(EXESUF) > check-qtest-s390x-y += tests/migration-test$(EXESUF) > @@ -750,6 +753,7 @@ tests/ipoctal232-test$(EXESUF): tests/ipoctal232-test.o > tests/qom-test$(EXESUF): tests/qom-test.o > tests/test-hmp$(EXESUF): tests/test-hmp.o > tests/machine-none-test$(EXESUF): tests/machine-none-test.o > +tests/device_del-test$(EXESUF): tests/device_del-test.o > tests/drive_del-test$(EXESUF): tests/drive_del-test.o $(libqos-virtio-obj-y) > tests/nvme-test$(EXESUF): tests/nvme-test.o $(libqos-pc-obj-y) > tests/pvpanic-test$(EXESUF): tests/pvpanic-test.o > diff --git a/tests/device_del-test.c b/tests/device_del-test.c > new file mode 100644 > index 0000000000..cbc3e78e56 > --- /dev/null > +++ b/tests/device_del-test.c > @@ -0,0 +1,103 @@ > +/* > + * QEMU device_del handling > + * > + * Copyright (C) 2019 Red Hat Inc. > + * > + * Authors: > + * David Hildenbrand <da...@redhat.com> > + * > + * This work is licensed under the terms of the GNU GPL, version 2 or later. > + * See the COPYING file in the top-level directory. > + */ > + > +#include "qemu/osdep.h" > +#include "libqtest.h" > +#include "qapi/qmp/qdict.h" > +#include "qapi/qmp/qstring.h" > + > +static void device_del_request(const char *id) > +{ > + QDict *resp; > + > + resp = qmp("{'execute': 'device_del', 'arguments': { 'id': %s } }", id); > + g_assert(qdict_haskey(resp, "return")); > + qobject_unref(resp); > +} > + > +static void system_reset(void) > +{ > + QDict *resp; > + > + resp = qmp("{'execute': 'system_reset'}"); > + g_assert(qdict_haskey(resp, "return")); > + qobject_unref(resp); > +} > + > +static void wait_device_deleted_event(const char *id) > +{ > + QDict *resp, *data; > + QObject *device; > + QString *qstr; > + > + /* > + * Other devices might get removed along with the removed device. Skip > + * these. > + */ > + for (;;) { > + resp = qtest_qmp_eventwait_ref(global_qtest, "DEVICE_DELETED"); > + data = qdict_get_qdict(resp, "data"); > + if (!data) { > + qobject_unref(resp); > + continue; > + } > + device = qdict_get(data, "device"); > + if (!device) { > + qobject_unref(resp); > + continue; > + } > + qstr = qobject_to(QString, device); > + g_assert(qstr); > + if (!strcmp(qstring_get_str(qstr), id)) { > + qobject_unref(data); ... this ^^ causes... > + qobject_unref(resp); ... this ^^ to crash with: /ppc64/device_del/pci_device_del_request: *** Error in `tests/device_del-test': corrupted double-linked list: 0x0000010021d58c10 *** IIUC, qobject_unref(resp) eventually calls qobject_unref(data) internally, so you shouldn't do it. If I drop the line, the test passes like a charm. > + break; > + } > + qobject_unref(data); I couldn't have the test executing this path but I guess it has the very same problem. > + qobject_unref(resp); > + } > +} > + > +static void test_pci_device_del_request(void) > +{ > + char *args; > + > + args = g_strdup_printf("-device virtio-mouse-pci,id=dev0"); > + qtest_start(args); > + > + /* > + * Request device removal. As the guest is not running, the request won't > + * be processed. However during system reset, the removal will be > + * handled, removing the device. > + */ > + device_del_request("dev0"); > + system_reset(); > + wait_device_deleted_event("dev0"); > + > + qtest_end(); > + g_free(args); > +} > + > +int main(int argc, char **argv) > +{ > + g_test_init(&argc, &argv, NULL); > + > + /* > + * We need a system that will process unplug requests during system > resets > + * and does not do PCI surprise removal. This holds for x86 ACPI, > + * s390x and spapr. > + */ > + qtest_add_func("/device_del/pci_device_del_request", > + test_pci_device_del_request); > + > + return g_test_run(); > +}