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  PHC 
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Mon, 04 Jan 2010 00:35:31 +0100
From:	Bartłomiej Zimoń <>
Subject: Re: [suspend/resume] Re: userspace notification from module

Dnia 4 stycznia 2010 0:30 "Rafael J. Wysocki" <> napisał(a):

> On Sunday 03 January 2010, Bartłomiej Zimoń wrote:
> > Dnia 3 stycznia 2010 22:29 "Rafael J. Wysocki" <> napisał(a):
> ...
> > 
> > It could be even UIO module but there are no pm events reachable there?
> > 
> > If it is not clean, we must extend pm-utils or write something new
> > (with backends dbus, ipc, scripts, ...)
> > But You see? We still have no information from kernel about events 
> > (especialy resume) or maybe i dont see this ;/
> They are available to the process that tells the kernel to suspend.
> Namely, to tell the kernel to suspend to RAM, the process (call it a power
> manager) needs to (for example) fprintf() "mem" to /sys/power/state.  As soon
> as this happens, the kernel will start to freeze processes (except for the
> power manager itself), so the power manager knows that everything should be
> ready for the suspend before it writes to /sys/power/state.  It doesn't need
> the kernel to tell it when the suspend is going to start, because it _knows_
> that in advance.
> Now, the fprintf() used to trigger the suspend will not return until the resume
> is complete.  So, again, when the fprintf() returns, the power manager will know
> that the resume has just finished (more precisely, the kernel side of it has
> just finished).
> There simply is no need for any special communication between the kernel and
> the power manager.

Thx Rafael - now it clear to me.
And what do You think about sending extra signals to processes?

Best regards.
Bartłomiej Zimoń
PLD Linux, Kadu Team, FreeRunner user

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

Powered by blists - more mailing lists