Re: [stable] [regression] Re: [213/474] x86, hotplug: Use mwait to offline a processor, fix the legacy case

On Sun, Aug 28, 2011 at 01:40:04PM -0500, Jonathan Nieder wrote:

Hi,

On 2011-03-17, Greg KH wrote:

quoted

2.6.33-longterm review patch.  If anyone has any objections, please let us know.

[...]

quoted

From: H. Peter Anvin <redacted>

upstream ea53069231f9317062910d6e772cca4ce93de8c8
x86, hotplug: Use mwait to offline a processor, fix the legacy case

Here included also some small follow-on patches to the same code:

[...]

quoted

https://bugzilla.kernel.org/show_bug.cgi?id=5471

Signed-off-by: H. Peter Anvin <redacted>
Signed-off-by: Len Brown <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Sorry for the sloow response.  Unfortunately this is reported to have
broken hibernation on two machines: an EeePC 1002HA and an Ideapad S10-3.
Frédéric writes:

| I've observed that when resuming from hibernation, sometimes my computer was
| returning to Grub2's menu (without any error message), and I had to do a
| "normal" boot on my Debian Squeeze system (with file systems corrections),
| loosing my hibernation's state.
|   The fail isn't automatic, but seems to happen more frequently after a while
| my computer was disconnected from AC and battery.

Noticed on Debian squeeze (which is based on v2.6.32.y), confirmed
with unpatched v2.6.32.45 and v2.6.33.18.  Backing out the patch
mentioned above avoids trouble.  A newer kernel (based on v2.6.39.y)
does _not_ exhibit the same problem, so it looks like the problem was
introduced in backporting.  http://bugs.debian.org/622259 has
details.

Thanks for letting me know, I'll go revert that patch for the next .32
and .33 longterm releases and let everyone else work out exactly what
the problem is, if they want to.

greg k-h