Re: [PATCH 09/17] soundwire: stream: remove unnecessary variable initializations

[Pierre-Louis Bossart]

On 8/6/19 10:31 AM, Cezary Rojewski wrote:
> On 2019-08-06 02:55, Pierre-Louis Bossart wrote:
> > @@ -1493,6 +1493,11 @@ static int _sdw_prepare_stream(struct 
> > sdw_stream_runtime *stream)
> > ÂÂÂÂÂÂÂÂÂ }
> > ÂÂÂÂÂ }
> > +ÂÂÂ if (!bus) {
> > +ÂÂÂÂÂÂÂ pr_err("Configuration error in %s\n", __func__);
> > +ÂÂÂÂÂÂÂ return -EINVAL;
> > +ÂÂÂ }
> > +
>
> This should probably be located in separate path - not at all an 
> initialization removal.

It's a consequence of the initialization removal: because we are 
removing the default init, there is a risk that the loop just before do 
not set it, so it's required to trap the case where the variable in not 
initialized.

> > @@ -1573,6 +1578,11 @@ static int _sdw_enable_stream(struct 
> > sdw_stream_runtime *stream)
> > ÂÂÂÂÂÂÂÂÂ }
> > ÂÂÂÂÂ }
> > +ÂÂÂ if (!bus) {
> > +ÂÂÂÂÂÂÂ pr_err("Configuration error in %s\n", __func__);
> > +ÂÂÂÂÂÂÂ return -EINVAL;
> > +ÂÂÂ }
> > +
>
> Same here.

same reply

> > @@ -1639,13 +1650,14 @@ static int _sdw_disable_stream(struct 
> > sdw_stream_runtime *stream)
> > ÂÂÂÂÂ ret = do_bank_switch(stream);
> > ÂÂÂÂÂ if (ret < 0) {
> > -ÂÂÂÂÂÂÂ dev_err(bus->dev, "Bank switch failed: %d\n", ret);
> > +ÂÂÂÂÂÂÂ pr_err("Bank switch failed: %d\n", ret);
> > ÂÂÂÂÂÂÂÂÂ return ret;
> > ÂÂÂÂÂ }
>
> Here too.

no, same thing, the bus variable is initialized in loops so tools will 
report a possible path where bus->dev is an invalid dereference.

> I might have missed something though I bet you got my point.