Bug: Resume with Host Protected Area

Bug: Resume with Host Protected Area

[Shane Hathaway]

Until today, I haven't been able to reliably put my ThinkPad T41 to
sleep.  After resuming, it generated lots of disk errors, and only a
reboot would bring it back to sanity.

Today I finally realized what's going on.  This laptop has a 3.5 GB
protected area at the end of the drive.  Linux disables the protection
on bootup (making the whole drive available), but the laptop apparently
re-enables the protection during the sleep cycle.  So I moved my
partitions out of the protected area and now the laptop finally resumes
correctly.  Yehaw!

The bugfix should be simple: call idedisk_check_hpa() during resume.

I'm not subscribed to this list, so please CC me on replies.

Shane

Re: Bug: Resume with Host Protected Area

[Greg Freemyer]

IMHO, if you are going to put live data in the HPA, you really should
just kill the HPA permanently not depend on Linux to do a volitile
reset on every reboot/resume.

See setmax at http://www.win.tue.nl/~aeb/linux/setmax.c 

You can compile that and use it to permanently modify your HPA setting.

use the -m (--max) option to permanently modify your HPA setting.

You can also use -d to make volitile changes.  IIRC, volitile changes
to are reset on every power cycle of the drive.

HTH,
Greg
-- 
Greg Freemyer

On 4/19/05, Shane Hathaway <shane@hathawaymix.org> wrote:
> Until today, I haven't been able to reliably put my ThinkPad T41 to
> sleep.  After resuming, it generated lots of disk errors, and only a
> reboot would bring it back to sanity.
> 
> Today I finally realized what's going on.  This laptop has a 3.5 GB
> protected area at the end of the drive.  Linux disables the protection
> on bootup (making the whole drive available), but the laptop apparently
> re-enables the protection during the sleep cycle.  So I moved my
> partitions out of the protected area and now the laptop finally resumes
> correctly.  Yehaw!
> 
> The bugfix should be simple: call idedisk_check_hpa() during resume.
> 
> I'm not subscribed to this list, so please CC me on replies.
> 
> Shane
> -
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> 


-- 
Greg Freemyer
The Norcross Group
Forensics for the 21st Century

Re: Bug: Resume with Host Protected Area

[Shane Hathaway]

Greg Freemyer wrote:
> IMHO, if you are going to put live data in the HPA, you really should
> just kill the HPA permanently not depend on Linux to do a volitile
> reset on every reboot/resume.
>
> See setmax at http://www.win.tue.nl/~aeb/linux/setmax.c 

Thanks for the pointer.

Still, I'm thinking of all the others who may have fallen into the same
trap.  I got into this situation purely by accident--I was never made
aware of HPA at installation time; Linux must have disabled it
automatically.  Then it took me a year to guess that the problems with
sleeping might be related to some peculiar messages I saw in the kernel
logs.

The HPA support needs to be all or nothing: either Linux disables HPA
automatically at boot *and* at resume, or it doesn't touch HPA at all.
Also, HPA shouldn't be disabled without user consent.  IBM put the
Windows installer in my laptop's HPA rather than provide installation
CDs.  There were no partition table entries indicating there was
anything stored at the end of the drive, so when I installed Linux, I
wiped out the Windows installer without knowing it.  IBM still hasn't
sent the replacement CDs.

Shane