Re: [PATCH][RFC v7] timekeeping: Ignore the bogus sleep time if pm_trace is enabled

From: Rafael J. Wysocki
Date: Thu Nov 10 2016 - 20:20:00 EST


On Thursday, November 10, 2016 10:26:09 AM John Stultz wrote:
> On Wed, Nov 9, 2016 at 8:55 PM, Chen Yu <yu.c.chen@xxxxxxxxx> wrote:
> > Previously we encountered some memory overflow issues due to
> > the bogus sleep time brought by inconsistent rtc, which is
> > triggered when pm_trace is enabled, and we have fixed it
> > in recent kernel. However it's improper in the first place
> > to call __timekeeping_inject_sleeptime() in case that pm_trace
> > is enabled simply because that "hash" time value will wreckage
> > the timekeeping subsystem.
> >
> > This patch is originally written by Thomas, which would bypass
> > the bogus rtc interval when pm_trace is enabled.
> > Meanwhile, if system succeed to resume back with pm_trace set, the
> > users are warned to adjust the bogus rtc either by ntp-date or rdate,
> > by resetting pm_trace_rtc_abused to false, otherwise above tools might
> > not work as expected.
> >
> > Originally-from: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> > Cc: John Stultz <john.stultz@xxxxxxxxxx>
> > Cc: Xunlei Pang <xlpang@xxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Len Brown <lenb@xxxxxxxxxx>
> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > Cc: Pavel Machek <pavel@xxxxxx>
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Signed-off-by: Chen Yu <yu.c.chen@xxxxxxxxx>
>
>
> Looks ok to me. I'm queueing it up for testing. If no one objects
> (and I don't see any issues) I'll merge it to my tree and push it to
> -tip through Thomas.

No objections here, thanks John!

Cheers,
Rafael