Re: [PATCH v2] Add suspend/resume for HPET

Jeff Chua
2007-04-01T03:13:31Z

On 4/1/07, David Brownell <david-b@pacbell.net> wrote:
> for those will all get grouped together ... suspended "very late" and
> resumed "very early", regardless of when they get registered. Pretty
> much the driver model parts of what Linus was suggesting; clockevent
> bits would still be needed.

I tested your patch with CONFIG_NO_HZ=y, but it still hangs while
suspending to disk (before the percent saving).

But one discovery. I get tired of all these hangs, so I decided to
press some keys and the power button. Accidentally, the suspend
proceeded and successfully suspended!

I tried many more times, and discovered that to proceed with the
suspend, hit any 4 keys slowly. (e.g. "F1 F2 F3 F4", or "1 2 3 4").

My .config has CONFIG_NO_HZ=y and CONFIG_HIGH_RES_TIMERS=y, but I
suppose CONFIG_HIGH_RES_TIMERS=y gots nothing to do with the hang.

I went back with my vanilla 2.6.21-rc5 with Maxim's patch, and with
hitting the keys, I could suspend to disk with CONFIG_NO_HZ=y and
CONFIG_HIGH_RES_TIMERS=y.

Jeff.