[Qemu-devel] Re: [PATCH] Avoid divide by zero when there is no block device to migrate

[Pierre Riteau]

On 25 déc. 2010, at 21:52, Pierre Riteau wrote:

> When block migration is requested and no read-write block device is
> present, a divide by zero exception is triggered because
> total_sector_sum equals zero.
> 
> Signed-off-by: Pierre Riteau <address@hidden>
> ---
> block-migration.c |    6 +++++-
> 1 files changed, 5 insertions(+), 1 deletions(-)
> 
> diff --git a/block-migration.c b/block-migration.c
> index 1475325..d62d63e 100644
> --- a/block-migration.c
> +++ b/block-migration.c
> @@ -350,7 +350,11 @@ static int blk_mig_save_bulked_block(Monitor *mon, 
> QEMUFile *f)
>         }
>     }
> 
> -    progress = completed_sector_sum * 100 / block_mig_state.total_sector_sum;
> +    if (block_mig_state.total_sector_sum != 0) {
> +        progress = completed_sector_sum * 100 / 
> block_mig_state.total_sector_sum;
> +    } else {
> +        progress = 100;
> +    }
>     if (progress != block_mig_state.prev_progress) {
>         block_mig_state.prev_progress = progress;
>         qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
> -- 
> 1.7.3.4
> 


Comments, anyone?

-- 
Pierre Riteau -- PhD student, Myriads team, IRISA, Rennes, France
http://perso.univ-rennes1.fr/pierre.riteau/