[libvirt PATCH v2 2/5] nodedev: Handle NULL command variable

[Boris Fiuczynski]

On 6/22/21 9:53 PM, Jonathon Jongsma wrote:
> 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 at redhat.com>
> ---
>   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;
>   
> 

Reviewed-by: Boris Fiuczynski <fiuczy at linux.ibm.com>

-- 
Mit freundlichen Grüßen/Kind regards
    Boris Fiuczynski

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