Re: [PATCH 5.10 012/105] dmaengine: shdma: Fix runtime PM imbalance on error

From: Greg Kroah-Hartman
Date: Wed Mar 09 2022 - 08:41:10 EST


On Wed, Mar 09, 2022 at 01:35:09PM +0100, Pavel Machek wrote:
> On Wed 2022-03-09 12:58:46, Greg Kroah-Hartman wrote:
> > On Wed, Mar 09, 2022 at 11:54:20AM +0100, Pavel Machek wrote:
> > > Hi!
> > >
> > > > From: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
> > > >
> > > > [ Upstream commit 455896c53d5b803733ddd84e1bf8a430644439b6 ]
> > > >
> > > > pm_runtime_get_() increments the runtime PM usage counter even
> > > > when it returns an error code, thus a matching decrement is needed on
> > > > the error handling path to keep the counter balanced.
> > >
> > > This patch will break things.
> > >
> > > Notice that -ret is ignored (checked 4.4 and 5.10), so we don't
> > > actually abort/return error; we just printk. We'll do two
> > > pm_runtime_put's after the "fix".
> > >
> > > Please drop from -stable.
> > >
> > > It was discussed during AUTOSEL review:
> > >
> > > Date: Fri, 25 Feb 2022 14:25:10 +0800 (GMT+08:00)
> > > From: 刘永志 <lyz_cs@xxxxxxxxxx>
> > > To: pavel machek <pavel@xxxxxxx>
> > > Cc: sasha levin <sashal@xxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx,
> > > Subject: Re: [PATCH AUTOSEL 5.16 24/30] dmaengine: shdma: Fix runtime PM
> > > imbalance on error
> >
> > So 5.15 and 5.16 is ok, but older is not?
>
> I believe commit is wrong for mainline and all stable releases, and
> author seems to agree. Drop from everywhere.

Is it reverted in Linus's tree yet?

thanks,

greg k-h