[libvirt] [PATCH 11/24] hostdev: Remove redundant check

[John Ferlan]

On 03/07/2016 12:24 PM, Andrea Bolognani wrote:
> If 'last_processed_hostdev_vf != -1' is false then, since the
> loop counter 'i' starts at 0, 'i <= last_processed_hostdev_vf'
> can't possibly be true and the loop body will never be executed.
> 
> Hence, the first check is completely redundant and can be safely
> removed.
> ---
>  src/util/virhostdev.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 

Premise understood; however, Coverity has an issue...


> diff --git a/src/util/virhostdev.c b/src/util/virhostdev.c
> index 098207e..f08502b 100644
> --- a/src/util/virhostdev.c
> +++ b/src/util/virhostdev.c

Way back here:

507  	    virPCIDeviceListPtr pcidevs = NULL;

(1) Event var_tested_neg: 	Assigning: "last_processed_hostdev_vf" = a negative value.
Also see events: 	[negative_returns]

508  	    int last_processed_hostdev_vf = -1;


Eventually we enter this loop:

    for (i = 0; i < nhostdevs; i++) {
         virDomainHostdevDefPtr hostdev = hostdevs[i];
         if (!virHostdevIsPCINetDevice(hostdev))
             continue;
         if (virHostdevNetConfigReplace(hostdev, uuid,
                                        mgr->stateDir) < 0) {
             goto resetvfnetconfig;
         }
         last_processed_hostdev_vf = i;
    }


If for some reason we "continue" (or not) and eventually "goto resetvfnetconfig;"
before ever setting last_processed_hostdev_vf, then we get to the goto.,..

> @@ -718,8 +718,7 @@ virHostdevPreparePCIDevices(virHostdevManagerPtr hostdev_mgr,
>      }
>  
>   resetvfnetconfig:
> -    for (i = 0;
> -         last_processed_hostdev_vf != -1 && i <= last_processed_hostdev_vf; i++)

and last_processed_hostdev_vf still == -1

So that check needs to be there - perhaps just add an:

    if (last_processed_hostdev_vf > -1) {
    }

John

> +    for (i = 0; i <= last_processed_hostdev_vf; i++)
>          virHostdevNetConfigRestore(hostdevs[i], hostdev_mgr->stateDir, NULL);
>  
>   reattachdevs:
>