Re: [Qemu-devel] [PATCH +STABLE-0.14] exit if -drive specified is invalid instead of ignoring the "wrong" -drive

[Kevin Wolf <kwolf@redhat.com>]

Am 17.03.2011 08:58, schrieb Michael Tokarev:
> Trivial patch.  I've sent it yesterday but somehow it didn't
> reach the list.
> 
> This fixes the problem when qemu continues even if -drive specification
> is somehow invalid, resulting in a mess.  Applicable for both current
> master and for stable-0.14 (and 0.13 and 0.12 as well).
> 
> The prob can actually be seriuos: when you start guest with two drives
> and make an error in the specification of one of them, and the guest
> has something like a raid array on the two drives, guest may start failing
> that array or kick "missing" drives which may result in a mess - this is
> what actually happened to me, I did't want a resync at all, and a resync
> resulted in re-writing (and allocating) a 4TB virtual drive I used for
> testing, which in turn resulted in my filesystem filling up and whole
> thing failing badly.  Yes it was just testing VM, I experimented with
> larger raid arrays, but the end result was quite, well, unexpected.
> 
> Thanks!
> 
> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

Before I got a message like this and the guest started anyway:

    qemu-system-x86_64: -drive asdfj: Invalid parameter 'asdfj'

Now it exits like it should, but I don't get an error message any more.
Exiting silently isn't really nice either.

> ---
>  vl.c |    3 ++-
>  1 files changed, 2 insertions(+), 1 deletions(-)
> 
> diff --git a/vl.c b/vl.c
> index 8bcf2ae..79f996e 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2098,7 +2098,8 @@ int main(int argc, char **argv, char **envp)
>                            HD_OPTS);
>                  break;
>              case QEMU_OPTION_drive:
> -                drive_def(optarg);
> +                if (drive_def(optarg) == NULL)
> +                    exit(1);

Coding style requires braces here.

Kevin