Johan Hovold <johan@xxxxxxxxxx> writes: > On Thu, Dec 19, 2019 at 09:39:57AM +0100, Rafael J. Wysocki wrote: >> On Wed, Dec 18, 2019 at 9:56 AM Johan Hovold <johan@xxxxxxxxxx> wrote: >> > >> > On Wed, Dec 18, 2019 at 03:56:46PM +0900, Punit Agrawal wrote: >> > > Serdev sub-system claims all serial devices that are not already >> > > enumerated. As a result, no device node is created for serial port on >> > > certain boards such as the Apollo Lake based UP2. This has the >> > > unintended consequence of not being able to raise the login prompt via >> > > serial connection. >> > > >> > > Introduce a blacklist to reject devices that should not be treated as >> > > a serdev device. Add the Intel HS UART peripheral ids to the blacklist >> > > to bring back serial port on SoCs carrying them. >> > > >> > > Cc: stable@xxxxxxxxxxxxxxx >> > > Signed-off-by: Punit Agrawal <punit1.agrawal@xxxxxxxxxxxxx> >> > > Cc: Rob Herring <robh@xxxxxxxxxx> >> > > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> >> > > Cc: Johan Hovold <johan@xxxxxxxxxx> >> > > Cc: Hans de Goede <hdegoede@xxxxxxxxxx> >> > > --- >> > > >> > > Hi, >> > > >> > > The patch has been updated based on feedback recieved on the RFC[0]. >> > > >> > > Please consider merging if there are no objections. >> > >> > Rafael, I vaguely remember you arguing for a white list when we >> > discussed this at some conference. Do you have any objections to the >> > blacklist approach taken here? >> >> As a rule, I prefer whitelisting, because it only enables the feature >> for systems where it has been tested and confirmed to work. >> >> However, if you are convinced that in this particular case the feature >> should work on the vast majority of systems with a few possible >> exceptions, blacklisting is fine too. >> >> It all depends on what the majority is, at least in principle. > > Ok, thanks. I don't have a preference either way in this case simply > because I don't know the distribution you refer to. > > But if Hans thinks blacklisting is the way to go then let's do that. We > haven't had that many reports about this, but if that were to change > down the line, I guess we can always switch to whitelisting. > > Punit, feel free to add my > > Acked-by: Johan Hovold <johan@xxxxxxxxxx> > > after addressing the review comments you've gotten so far. Thanks Johan. I will post a new version with the updates and acks.