Re: [PATCH][RESEND] Revert "PM: ACPI: reboot: Use S5 for reboot"

[Josef Bacik]

On 3/17/21 12:14 PM, Kai-Heng Feng wrote:
> On Wed, Mar 17, 2021 at 11:19 PM Josef Bacik <josef@xxxxxxxxxxxxxx> wrote:
> > On 3/16/21 10:50 PM, Kai-Heng Feng wrote:
> > > Hi,
> > >
> > > On Wed, Mar 17, 2021 at 10:17 AM Josef Bacik <josef@xxxxxxxxxxxxxx> wrote:
> > > > This reverts commit d60cd06331a3566d3305b3c7b566e79edf4e2095.
> > > >
> > > > This patch causes a panic when rebooting my Dell Poweredge r440.  I do
> > > > not have the full panic log as it's lost at that stage of the reboot and
> > > > I do not have a serial console.  Reverting this patch makes my system
> > > > able to reboot again.
> > >
> > > But this patch also helps many HP laptops, so maybe we should figure
> > > out what's going on on Poweredge r440.
> > > Does it also panic on shutdown?
> >
> > Sure I'll test whatever to get it fixed, but I just wasted 3 days bisecting and
> > lost a weekend of performance testing on btrfs because of this regression, so
> > until you figure out how it broke it needs to be reverted so people don't have
> > to figure out why reboot suddenly isn't working.
>
> That's unfortunate to hear. However, I've been spending tons of time
> on bisecting kernels. To me it's just a normal part of kernel
> development so I won't call it "wasted".
>
> Feel free to revert the patch though.
>
> > Running "halt" has the same effect with and without your patch, it gets to
> > "system halted" and just sits there without powering off.  Not entirely sure why
> > that is, but there's no panic.
>
> What about shutdown? pm_power_off_prepare() is used by shutdown but
> it's not used by halt.

"shutdown now" works fine with and without your patch.  Thanks,

Josef