At the point where the error message is emitted, the field def->name is still set to "new device", so the error message becomes: Unable to start mediated device 'new device': ... Since the name doesn't contain anything useful, just omit it from the error message altogether. Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; Reviewed-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- src/node_device/node_device_driver.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c index 8a0a2c3847..0f13cb4849 100644 --- a/src/node_device/node_device_driver.c +++ b/src/node_device/node_device_driver.c @@ -847,8 +847,8 @@ nodeDeviceCreateXMLMdev(virConnectPtr conn, if (virMdevctlCreate(def, &uuid, &errmsg) < 0) { if (errmsg) virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to start mediated device '%s': %s"), - def->name, errmsg); + _("Unable to start mediated device: %s"), + errmsg); return NULL; }

In commit 68580a51, I removed the checks for NULL cmd variables because virCommandRun() already handles the case where it is called with a NULL cmd. Unfortunately, it handles this case by raising a generic error which is both unhelpful and overwrites our existing error message. So for example, when I attempt to create a mediated device with an invalid parent, I get the following output: virsh # nodedev-create mdev-test.xml error: Failed to create node device from mdev-test.xml error: internal error: invalid use of command API With this patch, I now get a useful error message again: virsh # nodedev-create mdev-test.xml error: Failed to create node device from mdev-test.xml error: internal error: unable to find parent device 'pci_0000_00_03_0' Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; --- src/node_device/node_device_driver.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c index 0f13cb4849..43a8c1bf60 100644 --- a/src/node_device/node_device_driver.c +++ b/src/node_device/node_device_driver.c @@ -799,6 +799,10 @@ virMdevctlCreate(virNodeDeviceDef *def, char **uuid, char **errmsg) MDEVCTL_CMD_CREATE, uuid, errmsg); + + if (!cmd) + return -1; + /* an auto-generated uuid is returned via stdout if no uuid is specified in * the mdevctl args */ if (virCommandRun(cmd, &status) < 0 || status != 0) @@ -819,6 +823,9 @@ virMdevctlDefine(virNodeDeviceDef *def, char **uuid, char **errmsg) MDEVCTL_CMD_DEFINE, uuid, errmsg); + if (!cmd) + return -1; + /* an auto-generated uuid is returned via stdout if no uuid is specified in * the mdevctl args */ if (virCommandRun(cmd, &status) < 0 || status != 0) @@ -925,6 +932,9 @@ virMdevctlStop(virNodeDeviceDef *def, char **errmsg) cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_STOP, NULL, errmsg); + if (!cmd) + return -1; + if (virCommandRun(cmd, &status) < 0 || status != 0) return -1; @@ -940,6 +950,9 @@ virMdevctlUndefine(virNodeDeviceDef *def, char **errmsg) cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_UNDEFINE, NULL, errmsg); + if (!cmd) + return -1; + if (virCommandRun(cmd, &status) < 0 || status != 0) return -1; @@ -955,6 +968,9 @@ virMdevctlStart(virNodeDeviceDef *def, char **errmsg) cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_START, NULL, errmsg); + if (!cmd) + return -1; + if (virCommandRun(cmd, &status) < 0 || status != 0) return -1;

This macro will be utilized in the following patch. Since mdevctl commands can fail with or without an error message, this macro makes it easy to print a fallback error in the case that the error message is not set. Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; --- src/node_device/node_device_driver.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c index 43a8c1bf60..eb85cc0439 100644 --- a/src/node_device/node_device_driver.c +++ b/src/node_device/node_device_driver.c @@ -57,6 +57,9 @@ VIR_ENUM_IMPL(virMdevctlCommand, ); +#define MDEVCTL_ERROR(msg) (msg && msg[0] != '\0' ? msg : _("Unknown error")) + + virDrvOpenStatus nodeConnectOpen(virConnectPtr conn, virConnectAuthPtr auth G_GNUC_UNUSED, @@ -1387,7 +1390,7 @@ nodeDeviceUndefine(virNodeDevice *device, if (virMdevctlUndefine(def, &errmsg) < 0) { virReportError(VIR_ERR_INTERNAL_ERROR, _("Unable to undefine mediated device: %s"), - errmsg && errmsg[0] ? errmsg : "Unknown Error"); + MDEVCTL_ERROR(errmsg)); goto cleanup; } ret = 0; @@ -1434,7 +1437,7 @@ nodeDeviceCreate(virNodeDevice *device, if (virMdevctlStart(def, &errmsg) < 0) { virReportError(VIR_ERR_INTERNAL_ERROR, _("Unable to create mediated device: %s"), - errmsg && errmsg[0] ? errmsg : "Unknown Error"); + MDEVCTL_ERROR(errmsg)); goto cleanup; } ret = 0;

Currently, we have three different types of mdevctl errors: 1. the command cannot be constructed ecause of unsatisfied preconditions 2. the command cannot be executed due to some error 3. the command is executed, but returns an error status These different failures are handled differently. Some cases set an error and return and error status, and some return a error message but do not set an error. This means that the caller has to check both whether the return value is negative and whether the errmsg parameter is non-NULL before deciding whether to report the error or not. The situation is further complicated by the fact that there are occasional instances where mdevctl exits with an error status but does not print an error message. This results in errmsg being an empty string "" (i.e. non-NULL). Simplify the situation by ensuring that virReportError() is called for all error conditions rather than returning an error message back to the calling function. Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; --- src/node_device/node_device_driver.c | 114 +++++++++++++++------------ 1 file changed, 65 insertions(+), 49 deletions(-) diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c index eb85cc0439..497db0006a 100644 --- a/src/node_device/node_device_driver.c +++ b/src/node_device/node_device_driver.c @@ -746,6 +746,8 @@ nodeDeviceGetMdevctlCommand(virNodeDeviceDef *def, case MDEVCTL_CMD_LAST: default: /* SHOULD NEVER HAPPEN */ + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unknown Command '%i'"), cmd_type); return NULL; } @@ -795,48 +797,62 @@ nodeDeviceGetMdevctlCommand(virNodeDeviceDef *def, static int -virMdevctlCreate(virNodeDeviceDef *def, char **uuid, char **errmsg) +virMdevctlCreate(virNodeDeviceDef *def, char **uuid) { int status; + g_autofree char *errmsg = NULL; g_autoptr(virCommand) cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_CREATE, uuid, - errmsg); + &errmsg); if (!cmd) return -1; /* an auto-generated uuid is returned via stdout if no uuid is specified in * the mdevctl args */ - if (virCommandRun(cmd, &status) < 0 || status != 0) + if (virCommandRun(cmd, &status) < 0) + return -1; + + if (status != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to start mediated device: %s"), + MDEVCTL_ERROR(errmsg)); return -1; + } /* remove newline */ *uuid = g_strstrip(*uuid); - return 0; } static int -virMdevctlDefine(virNodeDeviceDef *def, char **uuid, char **errmsg) +virMdevctlDefine(virNodeDeviceDef *def, char **uuid) { int status; + g_autofree char *errmsg = NULL; g_autoptr(virCommand) cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_DEFINE, - uuid, errmsg); + uuid, &errmsg); if (!cmd) return -1; /* an auto-generated uuid is returned via stdout if no uuid is specified in * the mdevctl args */ - if (virCommandRun(cmd, &status) < 0 || status != 0) + if (virCommandRun(cmd, &status) < 0) return -1; + if (status != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to define mediated device: %s"), + MDEVCTL_ERROR(errmsg)); + return -1; + } + /* remove newline */ *uuid = g_strstrip(*uuid); - return 0; } @@ -846,7 +862,6 @@ nodeDeviceCreateXMLMdev(virConnectPtr conn, virNodeDeviceDef *def) { g_autofree char *uuid = NULL; - g_autofree char *errmsg = NULL; if (!def->parent) { virReportError(VIR_ERR_XML_ERROR, "%s", @@ -854,11 +869,7 @@ nodeDeviceCreateXMLMdev(virConnectPtr conn, return NULL; } - if (virMdevctlCreate(def, &uuid, &errmsg) < 0) { - if (errmsg) - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to start mediated device: %s"), - errmsg); + if (virMdevctlCreate(def, &uuid) < 0) { return NULL; } @@ -928,55 +939,79 @@ nodeDeviceCreateXML(virConnectPtr conn, static int -virMdevctlStop(virNodeDeviceDef *def, char **errmsg) +virMdevctlStop(virNodeDeviceDef *def) { int status; g_autoptr(virCommand) cmd = NULL; + g_autofree char *errmsg = NULL; - cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_STOP, NULL, errmsg); + cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_STOP, NULL, &errmsg); if (!cmd) return -1; - if (virCommandRun(cmd, &status) < 0 || status != 0) + if (virCommandRun(cmd, &status) < 0) return -1; + if (status != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to destroy '%s': %s"), def->name, + MDEVCTL_ERROR(errmsg)); + return -1; + } + return 0; } static int -virMdevctlUndefine(virNodeDeviceDef *def, char **errmsg) +virMdevctlUndefine(virNodeDeviceDef *def) { int status; g_autoptr(virCommand) cmd = NULL; + g_autofree char *errmsg = NULL; - cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_UNDEFINE, NULL, errmsg); + cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_UNDEFINE, NULL, &errmsg); if (!cmd) return -1; - if (virCommandRun(cmd, &status) < 0 || status != 0) + if (virCommandRun(cmd, &status) < 0) return -1; + if (status != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to undefine mediated device: %s"), + MDEVCTL_ERROR(errmsg)); + return -1; + } + return 0; } static int -virMdevctlStart(virNodeDeviceDef *def, char **errmsg) +virMdevctlStart(virNodeDeviceDef *def) { int status; g_autoptr(virCommand) cmd = NULL; + g_autofree char *errmsg = NULL; - cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_START, NULL, errmsg); + cmd = nodeDeviceGetMdevctlCommand(def, MDEVCTL_CMD_START, NULL, &errmsg); if (!cmd) return -1; - if (virCommandRun(cmd, &status) < 0 || status != 0) + if (virCommandRun(cmd, &status) < 0) return -1; + if (status != 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Unable to create mediated device: %s"), + MDEVCTL_ERROR(errmsg)); + return -1; + } + return 0; } @@ -1204,7 +1239,6 @@ nodeDeviceDestroy(virNodeDevicePtr device) g_autofree char *vfiogroup = virMediatedDeviceGetIOMMUGroupDev(def->caps->data.mdev.uuid); VIR_AUTOCLOSE fd = -1; - g_autofree char *errmsg = NULL; if (!vfiogroup) goto cleanup; @@ -1218,13 +1252,9 @@ nodeDeviceDestroy(virNodeDevicePtr device) goto cleanup; } - if (virMdevctlStop(def, &errmsg) < 0) { - if (errmsg) - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to destroy '%s': %s"), def->name, - errmsg); + if (virMdevctlStop(def) < 0) goto cleanup; - } + ret = 0; } else { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", @@ -1299,7 +1329,6 @@ nodeDeviceDefineXML(virConnect *conn, g_autoptr(virNodeDeviceDef) def = NULL; const char *virt_type = NULL; g_autofree char *uuid = NULL; - g_autofree char *errmsg = NULL; g_autofree char *name = NULL; virCheckFlags(0, NULL); @@ -1327,10 +1356,7 @@ nodeDeviceDefineXML(virConnect *conn, return NULL; } - if (virMdevctlDefine(def, &uuid, &errmsg) < 0) { - if (errmsg) - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to define mediated device: %s"), errmsg); + if (virMdevctlDefine(def, &uuid) < 0) { return NULL; } @@ -1385,14 +1411,9 @@ nodeDeviceUndefine(virNodeDevice *device, } if (nodeDeviceHasCapability(def, VIR_NODE_DEV_CAP_MDEV)) { - g_autofree char *errmsg = NULL; - - if (virMdevctlUndefine(def, &errmsg) < 0) { - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to undefine mediated device: %s"), - MDEVCTL_ERROR(errmsg)); + if (virMdevctlUndefine(def) < 0) goto cleanup; - } + ret = 0; } else { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", @@ -1432,14 +1453,9 @@ nodeDeviceCreate(virNodeDevice *device, goto cleanup; if (nodeDeviceHasCapability(def, VIR_NODE_DEV_CAP_MDEV)) { - g_autofree char *errmsg = NULL; - - if (virMdevctlStart(def, &errmsg) < 0) { - virReportError(VIR_ERR_INTERNAL_ERROR, - _("Unable to create mediated device: %s"), - MDEVCTL_ERROR(errmsg)); + if (virMdevctlStart(def) < 0) goto cleanup; - } + ret = 0; } else { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",

When trying to destroy a node device that is not active, we end up with a confusing error message: # nodedev-destroy mdev_88a6b868_46bd_4015_8e5b_26107f82da38 error: Failed to destroy node device 'mdev_88a6b868_46bd_4015_8e5b_26107f82da38' error: failed to access '/sys/bus/mdev/devices/88a6b868-46bd-4015-8e5b-26107f82da38/iommu_group': No such file or directory With this patch, the error is more clear: # nodedev-destroy mdev_88a6b868_46bd_4015_8e5b_26107f82da38 error: Failed to destroy node device 'mdev_88a6b868_46bd_4015_8e5b_26107f82da38' error: Requested operation is not valid: Device 'mdev_88a6b868_46bd_4015_8e5b_26107f82da38' is not active Signed-off-by: Jonathon Jongsma <jjongsma(a)redhat.com&gt; --- src/node_device/node_device_driver.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/src/node_device/node_device_driver.c b/src/node_device/node_device_driver.c index 497db0006a..721ba96203 100644 --- a/src/node_device/node_device_driver.c +++ b/src/node_device/node_device_driver.c @@ -1227,6 +1227,15 @@ nodeDeviceDestroy(virNodeDevicePtr device) ret = 0; } else if (nodeDeviceHasCapability(def, VIR_NODE_DEV_CAP_MDEV)) { + g_autofree char *vfiogroup = NULL; + VIR_AUTOCLOSE fd = -1; + + if (!virNodeDeviceObjIsActive(obj)) { + virReportError(VIR_ERR_OPERATION_INVALID, + _("Device '%s' is not active"), def->name); + goto cleanup; + } + /* If this mediated device is in use by a vm, attempting to stop it * will block until the vm closes the device. The nodedev driver * cannot query the hypervisor driver to determine whether the device @@ -1236,10 +1245,7 @@ nodeDeviceDestroy(virNodeDevicePtr device) * to be opened by one user at a time. So if we get EBUSY when opening * the group, we infer that the device is in use and therefore we * shouldn't try to remove the device. */ - g_autofree char *vfiogroup = - virMediatedDeviceGetIOMMUGroupDev(def->caps->data.mdev.uuid); - VIR_AUTOCLOSE fd = -1; - + vfiogroup = virMediatedDeviceGetIOMMUGroupDev(def->caps->data.mdev.uuid); if (!vfiogroup) goto cleanup;