diff mbox series

media: dvb_dummy_fe: Add error messages in case of attach failure

Message ID 20191107013745.22147-1-dwlsalmeida@gmail.com (mailing list archive)
State New, archived
Headers show
Series media: dvb_dummy_fe: Add error messages in case of attach failure | expand

Commit Message

Daniel Almeida Nov. 7, 2019, 1:37 a.m. UTC 
From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>

Complain if the attach functions fail, for any reason. This is helpful
when debugging.

Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
---
 drivers/media/dvb-frontends/dvb_dummy_fe.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

Comments

Mauro Carvalho Chehab Nov. 30, 2019, 6:54 a.m. UTC | #1 
Em Wed,  6 Nov 2019 22:37:45 -0300
"Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu:

> From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>
> 
> Complain if the attach functions fail, for any reason. This is helpful
> when debugging.
> 
> Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
> Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>

Looks OK to me.

> ---
>  drivers/media/dvb-frontends/dvb_dummy_fe.c | 18 +++++++++++++++---
>  1 file changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/media/dvb-frontends/dvb_dummy_fe.c b/drivers/media/dvb-frontends/dvb_dummy_fe.c
> index 4db679cb70ad..ca86857c3667 100644
> --- a/drivers/media/dvb-frontends/dvb_dummy_fe.c
> +++ b/drivers/media/dvb-frontends/dvb_dummy_fe.c
> @@ -114,12 +114,16 @@ struct dvb_frontend* dvb_dummy_fe_ofdm_attach(void)
>  	/* allocate memory for the internal state */
>  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
>  	if (!state)
> -		return NULL;
> +		goto err;
>  
>  	/* create dvb_frontend */
>  	memcpy(&state->frontend.ops, &dvb_dummy_fe_ofdm_ops, sizeof(struct dvb_frontend_ops));
>  	state->frontend.demodulator_priv = state;
>  	return &state->frontend;
> +
> +err:
> +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> +	return NULL;
>  }
>  
>  static const struct dvb_frontend_ops dvb_dummy_fe_qpsk_ops;
> @@ -131,12 +135,16 @@ struct dvb_frontend *dvb_dummy_fe_qpsk_attach(void)
>  	/* allocate memory for the internal state */
>  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
>  	if (!state)
> -		return NULL;
> +		goto err;
>  
>  	/* create dvb_frontend */
>  	memcpy(&state->frontend.ops, &dvb_dummy_fe_qpsk_ops, sizeof(struct dvb_frontend_ops));
>  	state->frontend.demodulator_priv = state;
>  	return &state->frontend;
> +
> +err:
> +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> +	return NULL;
>  }
>  
>  static const struct dvb_frontend_ops dvb_dummy_fe_qam_ops;
> @@ -148,12 +156,16 @@ struct dvb_frontend *dvb_dummy_fe_qam_attach(void)
>  	/* allocate memory for the internal state */
>  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
>  	if (!state)
> -		return NULL;
> +		goto err;
>  
>  	/* create dvb_frontend */
>  	memcpy(&state->frontend.ops, &dvb_dummy_fe_qam_ops, sizeof(struct dvb_frontend_ops));
>  	state->frontend.demodulator_priv = state;
>  	return &state->frontend;
> +
> +err:
> +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> +	return NULL;
>  }
>  
>  static const struct dvb_frontend_ops dvb_dummy_fe_ofdm_ops = {



Cheers,
Mauro
Sean Young Dec. 31, 2019, 9:47 a.m. UTC | #2 
Hi Daniel, Mauro,

On Sat, Nov 30, 2019 at 07:54:15AM +0100, Mauro Carvalho Chehab wrote:
> Em Wed,  6 Nov 2019 22:37:45 -0300
> "Daniel W. S. Almeida" <dwlsalmeida@gmail.com> escreveu:
> 
> > From: "Daniel W. S. Almeida" <dwlsalmeida@gmail.com>
> > 
> > Complain if the attach functions fail, for any reason. This is helpful
> > when debugging.
> > 
> > Suggested-by: Shuah Khan <skhan@linuxfoundation.org>
> > Signed-off-by: Daniel W. S. Almeida <dwlsalmeida@gmail.com>
> 
> Looks OK to me.
> 
> > ---
> >  drivers/media/dvb-frontends/dvb_dummy_fe.c | 18 +++++++++++++++---
> >  1 file changed, 15 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/media/dvb-frontends/dvb_dummy_fe.c b/drivers/media/dvb-frontends/dvb_dummy_fe.c
> > index 4db679cb70ad..ca86857c3667 100644
> > --- a/drivers/media/dvb-frontends/dvb_dummy_fe.c
> > +++ b/drivers/media/dvb-frontends/dvb_dummy_fe.c
> > @@ -114,12 +114,16 @@ struct dvb_frontend* dvb_dummy_fe_ofdm_attach(void)
> >  	/* allocate memory for the internal state */
> >  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
> >  	if (!state)
> > -		return NULL;
> > +		goto err;
> >  
> >  	/* create dvb_frontend */
> >  	memcpy(&state->frontend.ops, &dvb_dummy_fe_ofdm_ops, sizeof(struct dvb_frontend_ops));
> >  	state->frontend.demodulator_priv = state;
> >  	return &state->frontend;
> > +
> > +err:
> > +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> > +	return NULL;
> >  }

If kzalloc() fails, it will already complain before returning. Lately we've
been removing error logs after kmalloc() failures. I'm sure someone will send
in patches reverting this if it gets merged.

Is this a good idea?

Sean

> >  
> >  static const struct dvb_frontend_ops dvb_dummy_fe_qpsk_ops;
> > @@ -131,12 +135,16 @@ struct dvb_frontend *dvb_dummy_fe_qpsk_attach(void)
> >  	/* allocate memory for the internal state */
> >  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
> >  	if (!state)
> > -		return NULL;
> > +		goto err;
> >  
> >  	/* create dvb_frontend */
> >  	memcpy(&state->frontend.ops, &dvb_dummy_fe_qpsk_ops, sizeof(struct dvb_frontend_ops));
> >  	state->frontend.demodulator_priv = state;
> >  	return &state->frontend;
> > +
> > +err:
> > +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> > +	return NULL;
> >  }
> >  
> >  static const struct dvb_frontend_ops dvb_dummy_fe_qam_ops;
> > @@ -148,12 +156,16 @@ struct dvb_frontend *dvb_dummy_fe_qam_attach(void)
> >  	/* allocate memory for the internal state */
> >  	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
> >  	if (!state)
> > -		return NULL;
> > +		goto err;
> >  
> >  	/* create dvb_frontend */
> >  	memcpy(&state->frontend.ops, &dvb_dummy_fe_qam_ops, sizeof(struct dvb_frontend_ops));
> >  	state->frontend.demodulator_priv = state;
> >  	return &state->frontend;
> > +
> > +err:
> > +	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
> > +	return NULL;
> >  }
> >  
> >  static const struct dvb_frontend_ops dvb_dummy_fe_ofdm_ops = {
> 
> 
> 
> Cheers,
> Mauro
diff mbox series

Patch

diff --git a/drivers/media/dvb-frontends/dvb_dummy_fe.c b/drivers/media/dvb-frontends/dvb_dummy_fe.c
index 4db679cb70ad..ca86857c3667 100644
--- a/drivers/media/dvb-frontends/dvb_dummy_fe.c
+++ b/drivers/media/dvb-frontends/dvb_dummy_fe.c
@@ -114,12 +114,16 @@  struct dvb_frontend* dvb_dummy_fe_ofdm_attach(void)
 	/* allocate memory for the internal state */
 	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
 	if (!state)
-		return NULL;
+		goto err;
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &dvb_dummy_fe_ofdm_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+err:
+	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
+	return NULL;
 }
 
 static const struct dvb_frontend_ops dvb_dummy_fe_qpsk_ops;
@@ -131,12 +135,16 @@  struct dvb_frontend *dvb_dummy_fe_qpsk_attach(void)
 	/* allocate memory for the internal state */
 	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
 	if (!state)
-		return NULL;
+		goto err;
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &dvb_dummy_fe_qpsk_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+err:
+	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
+	return NULL;
 }
 
 static const struct dvb_frontend_ops dvb_dummy_fe_qam_ops;
@@ -148,12 +156,16 @@  struct dvb_frontend *dvb_dummy_fe_qam_attach(void)
 	/* allocate memory for the internal state */
 	state = kzalloc(sizeof(struct dvb_dummy_fe_state), GFP_KERNEL);
 	if (!state)
-		return NULL;
+		goto err;
 
 	/* create dvb_frontend */
 	memcpy(&state->frontend.ops, &dvb_dummy_fe_qam_ops, sizeof(struct dvb_frontend_ops));
 	state->frontend.demodulator_priv = state;
 	return &state->frontend;
+
+err:
+	pr_err("%s: DVB Dummy frontend driver attach failed\n", __func__);
+	return NULL;
 }
 
 static const struct dvb_frontend_ops dvb_dummy_fe_ofdm_ops = {