Messages in this thread | | | Date | Sun, 4 Aug 2019 03:57:29 +0100 | From | Sean Young <> | Subject | Re: [PATCH v2 1/2] media: ir-kbd-i2c: convert to i2c_new_dummy_device() |
| |
On Sat, Aug 03, 2019 at 01:17:49PM -0300, Mauro Carvalho Chehab wrote: > Em Tue, 30 Jul 2019 19:55:54 +0200 > Wolfram Sang <wsa+renesas@sang-engineering.com> escreveu: > > > Convert this driver to use the new i2c_new_dummy_device() call and bail > > out if the dummy device cannot be registered to make failure more > > visible to the user. > > > > Please don't do that. > > At first glance, devm_* sounds a good idea, but we had enough issues > using it on media system. > > I don't mind mind much if some SoC specific would use it, but doing > it on generic drivers is a very bad idea. We have removed almost all > devm_* calls from the media system. > > The problem with devm is that it the de-allocation routines aren't > called during device unbind. They happen a way later, only when the > device itself is physically removed, or the driver is removed.
Yes, good point.
> That caused lots of headaches to debug memory lifetime issues on > media.
Indeed this becomes much more complex. Explicit freeing is much better.
Thanks, Sean
| |