On Fri, Feb 21, 2020 at 05:11:02PM +0900, Chanwoo Choi wrote: > On 2/21/20 4:06 PM, Greg Kroah-Hartman wrote: > > On Thu, Feb 20, 2020 at 11:47:41AM -0800, John Stultz wrote: > >> On Thu, Feb 20, 2020 at 11:15 AM Greg Kroah-Hartman > >> <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > >>> > >>> On Fri, Feb 21, 2020 at 01:37:04AM +0800, Orson Zhai wrote: > >>>> This reverts commit 4585fbcb5331fc910b7e553ad3efd0dd7b320d14. > >>>> > >>>> The name changing as devfreq(X) breaks some user space applications, > >>>> such as Android HAL from Unisoc and Hikey [1]. > >>>> The device name will be changed unexpectly after every boot depending > >>>> on module init sequence. It will make trouble to setup some system > >>>> configuration like selinux for Android. > >>>> > >>>> So we'd like to revert it back to old naming rule before any better > >>>> way being found. > >>>> > >>>> [1] https://protect2.fireeye.com/url?k=00fa721e-5d2a7af6-00fbf951-000babff32e3-95e4b92259b05656&u=https://lkml.org/lkml/2018/5/8/1042 > >>>> > >>>> Cc: John Stultz <john.stultz@xxxxxxxxxx> > >>>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > >>>> Cc: stable@xxxxxxxxxxxxxxx > >>>> Signed-off-by: Orson Zhai <orson.unisoc@xxxxxxxxx> > >>>> > >>>> --- > >>>> drivers/devfreq/devfreq.c | 4 +--- > >>>> 1 file changed, 1 insertion(+), 3 deletions(-) > >>>> > >>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > >>>> index cceee8b..7dcf209 100644 > >>>> --- a/drivers/devfreq/devfreq.c > >>>> +++ b/drivers/devfreq/devfreq.c > >>>> @@ -738,7 +738,6 @@ struct devfreq *devfreq_add_device(struct device *dev, > >>>> { > >>>> struct devfreq *devfreq; > >>>> struct devfreq_governor *governor; > >>>> - static atomic_t devfreq_no = ATOMIC_INIT(-1); > >>>> int err = 0; > >>>> > >>>> if (!dev || !profile || !governor_name) { > >>>> @@ -800,8 +799,7 @@ struct devfreq *devfreq_add_device(struct device *dev, > >>>> devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); > >>>> atomic_set(&devfreq->suspend_count, 0); > >>>> > >>>> - dev_set_name(&devfreq->dev, "devfreq%d", > >>>> - atomic_inc_return(&devfreq_no)); > >>>> + dev_set_name(&devfreq->dev, "%s", dev_name(dev)); > >>>> err = device_register(&devfreq->dev); > >>>> if (err) { > >>>> mutex_unlock(&devfreq->lock); > >>>> -- > >>>> 2.7.4 > >>>> > >>> > >>> Thanks for this, I agree, this needs to get back to the way things were > >>> as it seems to break too many existing systems as-is. > >>> > >>> I'll queue this up in my tree now, thanks. > >> > >> Oof this old thing. I unfortunately didn't get back to look at the > >> devfreq name node issue or the compatibility links, since the impact > >> of the regression (breaking the powerHAL's interactions with the gpu) > >> wasn't as big as other problems we had. While the regression was > >> frustrating, my only hesitancy at this point is that its been this way > >> since 4.10, so reverting the problematic patch is likely to break any > >> new users since then. > > > > Looks like most users just revert that commit in their trees: > > https://protect2.fireeye.com/url?k=1012ad0f-4dc2a5e7-10132640-000babff32e3-35779c5ed675ef0f&u=https://source.codeaurora.org/quic/la/kernel/msm-4.14/commit/drivers/devfreq?h=msm-4.14&id=ccf273f6d89ad0fa8032e9225305ad6f62c7770c > > > > So we should be ok here. > > I'm sorry about changing the devfreq node name. > > OK. Do you pick this patch to your tree? Yes, I can do that. > or If not, I'll apply it to devfreq-next branch for v5.7-rc1. > > And do you apply it to kernel of linux-stable tree since 4.11? Yeah, I'll mark it for stable. Can I get an ack from you for this? thanks, greg k-h
