[libvirt] [PATCH] qemu: fix return value issue

[Daniel Veillard]

On Mon, Aug 01, 2011 at 05:05:28PM +0800, ajia at redhat.com wrote:
> whether or not previous return value is -1, the following codes will be 
> executed for a inactive guest in src/qemu/qemu_driver.c:
> ret = virDomainSaveConfig(driver->configDir, persistentDef);
> and if everything is okay, 'ret' is assigned to 0, the previous 'ret'
> will be overwritten, this patch will fix this issue.  
> 
> * src/qemu/qemu_driver.c: avoid return value is overwritten when give a argument
>   in out of blkio weight range for a inactive guest.
> 
> * how to reproduce?
>   % virsh blkiotune ${guestname} --weight 10
>   % echo $?
> 
>   Note: guest must be inactive, argument 10 in out of blkio weight range, 
>   however, virsh hasn't raised any error information, and return value is 0.
> 
>   https://bugzilla.redhat.com/show_bug.cgi?id=726304
> 
> Signed-off-by: Alex Jia <ajia at redhat.com>
> ---
>  src/qemu/qemu_driver.c |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
> 
> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> index b673fd5..aaccddf 100644
> --- a/src/qemu/qemu_driver.c
> +++ b/src/qemu/qemu_driver.c
> @@ -5688,7 +5688,9 @@ static int qemuDomainSetBlkioParameters(virDomainPtr dom,
>                  ret = -1;
>              }
>          }
> -        ret = virDomainSaveConfig(driver->configDir, persistentDef);
> +
> +        if(virDomainSaveConfig(driver->configDir, persistentDef) < 0)
> +            goto cleanup;
>      }

  Doesn't sound right either because then we fail to report if the
SaveConfig operation fails

  The following fixes the issues you raise and still report failues
of saving config files:

Daniel

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index b673fd5..ef6f34f 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -5688,7 +5688,8 @@ static int qemuDomainSetBlkioParameters(virDomainPtr dom,
                 ret = -1;
             }
         }
-        ret = virDomainSaveConfig(driver->configDir, persistentDef);
+        if (virDomainSaveConfig(driver->configDir, persistentDef) < 0)
+            ret = -1;
     }
 
 cleanup:

-- 
Daniel Veillard      | libxml Gnome XML XSLT toolkit  http://xmlsoft.org/
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