On Monday, July 17, 2017 11:34:57 AM Sudeep Holla wrote:
>
> On 17/07/17 08:01, Ulf Hansson wrote:
> > On 14 July 2017 at 12:51, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
> >> If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach
> >> may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets
> >> the PM domain for the device unconditionally.
> >>
> >> When subsequent attempts are made to call genpd_dev_pm_attach, it may
> >> return -EEXISTS checking dev->pm_domain without re-attempting to call
> >> attach_dev or power_on.
> >>
> >> platform_drv_probe then attempts to call drv->probe as the return value
> >> -EEXIST != -EPROBE_DEFER, which may end up in a situation where the
> >> device is accessed without it's power domain switched on.
> >>
> >> Fixes: f104e1e5ef57 ("PM / Domains: Re-order initialization of generic_pm_domain_data")
> >> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> >> Cc: Kevin Hilman <khilman@xxxxxxxxxx>
> >> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> >> Cc: <stable@xxxxxxxxxxxxxxx> # v4.0+
> >> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> >
> > Acked-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> >
> >> ---
> >> drivers/base/power/domain.c | 8 ++++----
> >> 1 file changed, 4 insertions(+), 4 deletions(-)
> >>
> >> Hi,
> >>
> >> I have added Cc/Fixes tags based on the original commit that caused the issue.
> >> I need to workout a patch that can cleanly apply before commit 989561de9b51
> >> ("PM / Domains: add setter for dev.pm_domain"), i.e. for v4.0.x to v4.4.x
> >> This patch should apply from v4.5.x onwards.
> >
> > Thanks for checking this.
> >
> > Perhaps we should change the stable tag to # v4.5+ instead then?
> > Otherwise the stable people will just report problems when trying to
> > apply it.
> >
>
> Yes, I know. I thought then I can work out the solution for whatever
> version they need. Instead of trying to post patch for all versions from
> v4.0 to v4.4
> If that's not acceptable, then yes it should be #4.5+
> Rafael, can you just update that if required ?
I can.
> I am fine to work a patch for v4.[0-4].x when requested.
That depends on how much of a problem this can be for the users of those
kernels, but I guess 4.4 is used by Android, so maybe it's worth the effort.
Thanks,
Rafael