2003-08-06 13:19:30

by MånsRullgård

[permalink] [raw]
Subject: Re: [Swsusp-devel] Re: [PATCH] Allow initrd_load() before software_resume() (version 2)

Pavel Machek <[email protected]> writes:

>> > > Okay. I hadn't tried it yet. I'll happily take up the barrow for you and
>> > > push it to Pavel and Linus with the rest, if you like.
>> >
>> > Don't even think about that.
>> >
>> > It is not safe to run userspace *before* doing resume. You don't want
>> > to see problems this would bring in. Forget it.
>> >
>> so how do you resume from a partition on a device mapper volume?
>>
>> (and yes I basically agree with your sentiment though)
>
> I know very little about DM, its very well possible that resume from
> it is not supported.

Since DM requires some userspace program to set up the mappings, it
seems to me that it wouldn't work to resume from a DM volume. I'd
much appreciate if it would work, somehow.

--
M?ns Rullg?rd
[email protected]


2003-08-11 13:41:17

by Rob Landley

[permalink] [raw]
Subject: Re: [Swsusp-devel] Re: [PATCH] Allow initrd_load() before software_resume() (version 2)

On Wednesday 06 August 2003 09:16, M?ns Rullg?rd wrote:
> Pavel Machek <[email protected]> writes:
> >> > > Okay. I hadn't tried it yet. I'll happily take up the barrow for you
> >> > > and push it to Pavel and Linus with the rest, if you like.
> >> >
> >> > Don't even think about that.
> >> >
> >> > It is not safe to run userspace *before* doing resume. You don't want
> >> > to see problems this would bring in. Forget it.
> >>
> >> so how do you resume from a partition on a device mapper volume?
> >>
> >> (and yes I basically agree with your sentiment though)
> >
> > I know very little about DM, its very well possible that resume from
> > it is not supported.
>
> Since DM requires some userspace program to set up the mappings, it
> seems to me that it wouldn't work to resume from a DM volume. I'd
> much appreciate if it would work, somehow.

Er, query:

At some point in the vague nebulous future, after initrd has become initramfs,
the partition detection code is scheduled to be ripped out, correct? And
replaced with a userspace thing run out of initrd ala hotplug and udev and
all that?

So at that point, it's not just device mapper that's going to need something
else to run in userspace to attach block devices to partitions. Everything
will.

So are you saying that swsusp is a short-term thing that will be dropped in
2.8 because it can't be made to work? Or that we WILL have to deal with this
at some point, just not yet?

Rob


2003-08-11 15:29:59

by Pavel Machek

[permalink] [raw]
Subject: Re: [Swsusp-devel] Re: [PATCH] Allow initrd_load() before software_resume() (version 2)

Hi!

> > >> > > Okay. I hadn't tried it yet. I'll happily take up the barrow for you
> > >> > > and push it to Pavel and Linus with the rest, if you like.
> > >> >
> > >> > Don't even think about that.
> > >> >
> > >> > It is not safe to run userspace *before* doing resume. You don't want
> > >> > to see problems this would bring in. Forget it.
> > >>
> > >> so how do you resume from a partition on a device mapper volume?
> > >>
> > >> (and yes I basically agree with your sentiment though)
> > >
> > > I know very little about DM, its very well possible that resume from
> > > it is not supported.
> >
> > Since DM requires some userspace program to set up the mappings, it
> > seems to me that it wouldn't work to resume from a DM volume. I'd
> > much appreciate if it would work, somehow.
>
> Er, query:
>
> At some point in the vague nebulous future, after initrd has become initramfs,
> the partition detection code is scheduled to be ripped out, correct? And
> replaced with a userspace thing run out of initrd ala hotplug and udev and
> all that?
>
> So at that point, it's not just device mapper that's going to need something
> else to run in userspace to attach block devices to partitions. Everything
> will.
>
> So are you saying that swsusp is a short-term thing that will be dropped in
> 2.8 because it can't be made to work? Or that we WILL have to deal with this
> at some point, just not yet?

At that point we'll have to carefully audit all userland code that can
run before software resume.
Pavel
--
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]