Hi
On Sat, December 31, 2011 11:54, Jonathan Nieder wrote:
> dvb_net_init unconditionally returns 0. Callers such as
> videobuf_dvb_register_frontend examine dvbnet->dvbdev instead of the
> return value to tell whether the operation succeeded. If it has been
> set to a valid pointer, success; if it was left equal to NULL,
> failure.
I noticed this when testing the MFE patch set a few years ago
now and as you have seen I tested for NULL elsewhere more as
a reminder than any thing else.
I made no changes either as you can also see since it was beyond
the scope of the MFE patches at the time. I do remember this
and it pops into my mind once in a while and now it can now be
cast aside forever, thanks.
> Alas, there is an edge case where that logic does not work as well:
> when network support has been compiled out (CONFIG_DVB_NET=n), we want
> dvb_net_init and related operations to behave as no-ops and always
> succeed, but there is no appropriate value to which to set dvb->dvbdev
> to indicate this.
I suspect this is the only case where the MFE patches do not
properly check every potential fault with attachment as I cannot
remember any other function being as the NET attachment which
may have actually been a void function when I last visited it
but that's a bit vague and the return 0 suggests not.
> Let dvb_net_init return a meaningful error code, as preparation for
> adapting callers to look at that instead.
>
> The only immediate impact of this patch should be to make the few
> callers that already check for an error code from dvb_net_init behave
> a little more sensibly when it fails.
Cheers, thanks for your efforts.
bye
> Signed-off-by: Jonathan Nieder <jrnieder@xxxxxxxxx>
> ---
> drivers/media/dvb/dvb-core/dvb_net.c | 4 +---
> 1 files changed, 1 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/dvb/dvb-core/dvb_net.c
> b/drivers/media/dvb/dvb-core/dvb_net.c
> index 93d9869e0f15..8766ce8c354d 100644
> --- a/drivers/media/dvb/dvb-core/dvb_net.c
> +++ b/drivers/media/dvb/dvb-core/dvb_net.c
> @@ -1510,9 +1510,7 @@ int dvb_net_init (struct dvb_adapter *adap, struct
> dvb_net *dvbnet,
> for (i=0; i<DVB_NET_DEVICES_MAX; i++)
> dvbnet->state[i] = 0;
>
> - dvb_register_device (adap, &dvbnet->dvbdev, &dvbdev_net,
> + return dvb_register_device(adap, &dvbnet->dvbdev, &dvbdev_net,
> dvbnet, DVB_DEVICE_NET);
> -
> - return 0;
> }
> EXPORT_SYMBOL(dvb_net_init);
--
// /
{:)==={ Darron Broad <darron@xxxxxxxx>
\\ \
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