APPLIED: [Unstable] [PATCH] UBUNTU: [Config] CONFIG_SATA_MOBILE_LPM_POLICY=3

[Seth Forshee]

On Thu, Mar 29, 2018 at 12:00:44PM +0800, Kai Heng Feng wrote:
> 
> > On Mar 29, 2018, at 1:32 AM, Seth Forshee <seth.forshee at canonical.com>
> > wrote:
> > 
> > On Wed, Mar 28, 2018 at 07:21:04PM +0800, Kai-Heng Feng wrote:
> > > BugLink: https://bugs.launchpad.net/bugs/1759547
> > > Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
> > > ---
> > >  debian.master/config/config.common.ubuntu | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/debian.master/config/config.common.ubuntu
> > > b/debian.master/config/config.common.ubuntu
> > > index e09a65ef0a1f..98a828b82f30 100644
> > > --- a/debian.master/config/config.common.ubuntu
> > > +++ b/debian.master/config/config.common.ubuntu
> > > @@ -7691,7 +7691,7 @@ CONFIG_SATA_DWC=m
> > >  CONFIG_SATA_DWC_OLD_DMA=y
> > >  CONFIG_SATA_HIGHBANK=y
> > >  CONFIG_SATA_INIC162X=m
> > > -CONFIG_SATA_MOBILE_LPM_POLICY=0
> > > +CONFIG_SATA_MOBILE_LPM_POLICY=3
> > 
> > From the commit message of the patch adding this:
> > 
> >   Also enabling LPM by default is not entirely without risk of
> >   regressions. At least min_power is known to cause issues with some
> >   disks, including some reports of data corruption.
> > 
> > Is there any risk of these issues with the value you've chosen here?
> 
> Yes, users in [1] can't mount rootfs with min_power.
> 
> I wrote a patch to quirk their devices to use med_power_with_dipm (i.e.
> CONFIG_SATA_MOBILE_LPM_POLICY=3),
> unfortunately their disk still have issues with this setting.
> 
> So yes, some disks are buggy under both min_power and med_power_with_dipm.
> 
> Since LPM can be set from userspace (e.g. laptop-mode-tools, TLP, powertop),
> user will likely to get hit by this bug, one way or another.
> 
> In a discussion with Hans [2], he mentioned that Fedora will use
> CONFIG_SATA_MOBILE_LPM_POLICY=3 from v4.15+,
> I think we should do the same.
> 
> Also, one of our customer does want us to use a saner default for laptops.

Thanks, applied to unstable/master. Did you also intend to request this
for bionic?