Re: [linux-pm] Re: [PATCH] Remove process freezer from suspend to RAM pathway

[Alan Stern <stern@rowland.harvard.edu>]

On Tue, 3 Jul 2007, Oliver Neukum wrote:

> Well, but you did remove sys_sync() from the freezer, which is
> and must be called in the hibernate path.

That's not really true.  We _want_ to call sys_sync() in both the 
hibernate and suspend paths (in case the batteries run down), to help 
avoid filesystem problems if something goes wrong with the resume.  But 
it isn't a hard requirement.

> > I'm not sure why this can't be made atomic, but assuming, that it
> > can't, fuse should still not need to be implicated.  If it is, that's
> > an indication about something wrong in the suspend procedure.
> 
> Nope, something's wrong in fuse. You must be able to deal with sync
> until every task is frozen.

That's ridiculous.  FUSE itself runs partially as a user task.  How can
you expect it to carry out a sync or anything else when it is frozen?

I suppose you could "deal" with it by having the kernel portion return
an error if the userspace part is frozen.  If the hibernate/suspend 
code bothered to check the return value, it would immediately abort 
the suspend.

Alan Stern

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/