From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nigel Cunningham Subject: Re: [RFC][PATCH -mm 3/3] PM: Disable _request_firmware before hibernation/suspend Date: Mon, 28 May 2007 18:30:26 +1000 Message-ID: <1180341026.14749.12.camel@nigel.suspend2.net> References: <200705272229.21263.rjw@sisk.pl> <200705272231.54535.rjw@sisk.pl> <20070527204955.GA22202@srcf.ucam.org> <200705272345.04518.rjw@sisk.pl> Reply-To: nigel@nigel.suspend2.net Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============2026220539276361525==" Return-path: In-Reply-To: <200705272345.04518.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Mime-version: 1.0 Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: Matthew Garrett , LKML , Pavel Machek , pm list List-Id: linux-pm@vger.kernel.org --===============2026220539276361525== Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-TeYUmiz5EeRIrG0UU77U" --=-TeYUmiz5EeRIrG0UU77U Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hi. On Sun, 2007-05-27 at 23:45 +0200, Rafael J. Wysocki wrote: > On Sunday, 27 May 2007 22:49, Matthew Garrett wrote: > > On Sun, May 27, 2007 at 10:31:53PM +0200, Rafael J. Wysocki wrote: > > > From: Rafael J. Wysocki > > >=20 > > > Use a hibernation and suspend notifier to disable the firmware reques= ting > > > mechanism before a hibernation/suspend and enable it after the operat= ion. > >=20 > > This avoids the problem of .resume methods calling userspace while=20 > > userspace is frozen and a resulting hang, but does it actually result i= n=20 > > the drivers beginning to work again? >=20 > Well, this was acutally invented before you've decided to remove the free= zing > of tasks from the suspend code path (which I think is a mistake, but that= 's > only my personal opinion, so it doesn't matter very much ;-)) and I regar= d it > as a workaround. Suspend-to-ram code paths shouldn't assume userspace is unfrozen anyway. Doesn't [u]swsusp have a code path like Suspend2 where we can suspend to ram after writing the hibernation image? In that case, it will still be possible that we seek to enter and leave S3 with processes frozen. Apologies if anyone has already mentioned this - I'm just starting to play catchup. Regards, Nigel --=-TeYUmiz5EeRIrG0UU77U Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQBGWpMiN0y+n1M3mo0RAsiAAKDgdGSlgBjRl4Yt5qHxrn6DYslkigCfYVXU F3kwH+POpwElE+WiSataFXI= =oI4M -----END PGP SIGNATURE----- --=-TeYUmiz5EeRIrG0UU77U-- --===============2026220539276361525== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============2026220539276361525==--