On Fri, Dec 4, 2020 at 9:57 AM Tzung-Bi Shih tzungbi@google.com wrote:
On Fri, Dec 4, 2020 at 4:36 PM Arnd Bergmann arnd@kernel.org wrote:
diff --git a/sound/soc/codecs/cros_ec_codec.c b/sound/soc/codecs/cros_ec_codec.c index 58894bf47514..6ec673573c70 100644 --- a/sound/soc/codecs/cros_ec_codec.c +++ b/sound/soc/codecs/cros_ec_codec.c @@ -348,7 +348,7 @@ static int i2s_rx_event(struct snd_soc_dapm_widget *w, }
return send_ec_host_command(priv->ec_device, EC_CMD_EC_CODEC_I2S_RX,
(uint8_t *)&p, sizeof(p), NULL, 0);
&p.cmd, sizeof(p.cmd), NULL, 0);
}
I would prefer your v1.
Reasons:
- The change is not just kernel related.
There is a EC (embedded controller) firmware to collaborate with the code. The firmware doesn't know the kernel only copies the first byte of the packet (at least for now). See https://chromium.googlesource.com/chromiumos/platform/ec/+/refs/heads/master....
- We don't copy partial packets in a EC host command.
IMHO, it is also not a big deal if copying a few unused bytes in the packet.
Ok, so if the EC does access the uninitialized data, then it is indeed better to initialize it to zero as I first thought.
Arnd