Re: [PATCH] PM: sleep: Add DPM watchdog to late/early/noirq phases

[Mayank Rungta]

On Wed, Sep 2, 2026 at 2:15 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Fri, Aug 21, 2026 at 3:37 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
> >
> > Hi,
> >
> > On Fri, Aug 21, 2026 at 10:06 AM Mayank Rungta <mrungta@xxxxxxxxxx> wrote:
> > >
> > > Extend the DPM watchdog to wrap device_suspend_late, device_suspend_noirq,
> > > device_resume_early, and device_resume_noirq callbacks. If a driver hangs
> > > during these transitions, the watchdog will fire and dump a stack trace
> > > to help identify the offending driver.
> > >
> > > To prevent false-positive timeouts, the watchdog is set only after
> > > waiting for subordinate (during suspend) and superior (during resume)
> > > devices.
> > >
> > > Signed-off-by: Mayank Rungta <mrungta@xxxxxxxxxx>
> > > ---
> > > Testing:
> > > - Tested on an ARM64 SoC (Pixel platform running a 6.18-based kernel with
> > >   DPM watchdog enabled; Android 6.18 kernel has latest DPM changes
> > >   backported).
> > >
> > >  drivers/base/power/main.c | 25 ++++++++++++++++++++++---
> > >  1 file changed, 22 insertions(+), 3 deletions(-)
> >
> > I reviewed this patch for Mayank before he sent it. It seems correct /
> > useful to me, so I'm happy with:
> >
> > Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
>
> Since I reviewed this patch, someone pointed out to me that we should
> probably also add the DPM watchdog to the "prepare" / "complete"
> stages too. I know those stages are used less-often, but it still
> seems like the DPM watchdog would be relevant there. Unless Rafael
> chimes in and says he disagrees or that he dislikes this patch in
> general, maybe you could post a v2 patch that adds that?
>
> Thanks!
>
> -Doug

Thanks Doug. I have posted v2 with prepare and complete support here:
https://lore.kernel.org/r/20260909224818.2177311-1-mrungta@xxxxxxxxxx