linux-kernel - Re: [RFC][PATCH] PM: Introduce new top level suspend and hibernation callbacks (rev. 6)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Pine.LNX.4.44L0.0804011653140.9362-100000@netrider.rowland.org>
Date:	Tue, 1 Apr 2008 16:56:55 -0400 (EDT)
From:	Alan Stern <stern@...land.harvard.edu>
To:	"Rafael J. Wysocki" <rjw@...k.pl>
cc:	Nigel Cunningham <ncunningham@...a.org.au>,
	pm list <linux-pm@...ts.linux-foundation.org>,
	ACPI Devel Maling List <linux-acpi@...r.kernel.org>,
	Greg KH <greg@...ah.com>, Len Brown <lenb@...nel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Alexey Starikovskiy <astarikovskiy@...e.de>,
	David Brownell <david-b@...bell.net>,
	Pavel Machek <pavel@....cz>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	Oliver Neukum <oliver@...kum.org>
Subject: Re: [RFC][PATCH] PM: Introduce new top level suspend and hibernation
 callbacks (rev. 6)

On Tue, 1 Apr 2008, Rafael J. Wysocki wrote:

> > Does ..._ext_... mean extended? (external?) If 'extended' (or if not),
> > does that imply that they're mutually exclusive alternatives for drivers
> > to use?
> 
> 'ext' means 'extended'.  The idea is that the 'extended' version will be used
> by bus types / driver types that don't need to implement the _noirq callbacks.

Something's wrong here.  This seems to say that the "extended" version
has _fewer_ method pointers -- in which case it should be called 
"restricted" instead.

> > So drivers can never validly fail to resume. That sounds fair enough. If
> > the hardware has gone away while in lower power mode (USB, say), should
> > the driver then just printk an error and return success?
> 
> I think so.
> 
> IMO, an error code returned by a driver's ->resume() should mean "the device
> hasn't resumed and is presumably dead".  Otherwise, ->resume() should return
> success.

If the device is gone, it doesn't much matter what resume() returns.

Alan Stern

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