Re: [PATCH] [3/48] Suspend2 2.1.9.8 for 2.6.12: 301-proc-acpi-sleep-activate-hook.patch

Nigel Cunningham
2005-07-12T06:43:31Z

Hi.

On Mon, 2005-07-11 at 09:03, Christoph Hellwig wrote:
> Please add an explanation why this is nessecary. Big NACK for the patch as-is, but
> to find a proper solution we need to know what you're actually doing.

When the user has an initrd or initramfs, they're supposed to include

echo > /proc/software_suspend/do_resume

at the point in their initrd where drivers needed for accessing the
image, encryption keys and so on have been set up, but the root fs has
not yet been mounted. If they don't do that, we should scream loudly,
because mounting the root fs (even read only) will replay the journal,
making the image not match what is on disk. This in turn can and
probably will result in hard disk corruption if they echo to do_resume
from say /etc/rc.d/rc.sysinit.

In addition, the try_to_freeze call is needed because, having loaded an
image, we freeze kernel threads before doing the atomic restore.

Regards,

Nigel
--
Evolution.
Enumerate the requirements.
Consider the interdependencies.
Calculate the probabilities.
Be amazed that people believe it happened.