Re: [Qemu-devel] [PATCH v3 20/21] mirror: Handle failure for potentially large allocations

[Benoît Canet]

The Tuesday 03 Jun 2014 à 15:11:01 (+0200), Kevin Wolf wrote :
> Some code in the block layer makes potentially huge allocations. Failure
> is not completely unexpected there, so avoid aborting qemu and handle
> out-of-memory situations gracefully.
> 
> This patch addresses the allocations in the mirror block job.
> 
> Signed-off-by: Kevin Wolf <address@hidden>
> Reviewed-by: Stefan Hajnoczi <address@hidden>
> ---
>  block/mirror.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/block/mirror.c b/block/mirror.c
> index 94c8661..07417d7 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -350,7 +350,12 @@ static void coroutine_fn mirror_run(void *opaque)
>      }
>  
>      end = s->common.len >> BDRV_SECTOR_BITS;
> -    s->buf = qemu_blockalign(bs, s->buf_size);
> +    s->buf = qemu_try_blockalign(bs, s->buf_size);
> +    if (s->buf == NULL) {
> +        ret = -ENOMEM;
> +        goto immediate_exit;
> +    }
> +
>      sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS;
>      mirror_free_init(s);
>  
> -- 
> 1.8.3.1
> 
> 
Reviewed-by: Benoit Canet <address@hidden>