All of lore.kernel.org
 help / color / mirror / Atom feed
From: Pavel Machek <pavel@ucw.cz>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Sebastian Capella <sebastian.capella@linaro.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>,
	"linaro-kernel@lists.linaro.org" <linaro-kernel@lists.linaro.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	Russ Dill <Russ.Dill@ti.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <len.brown@intel.com>, Nicolas Pitre <nico@linaro.org>,
	Santosh Shilimkar <santosh.shilimkar@ti.com>,
	Will Deacon <Will.Deacon@arm.com>,
	Cyril Chemparathy <cyril@ti.com>,
	Jonathan Austin <Jonathan.Austin@arm.com>,
	Catalin Marinas <Catalin.Marinas@arm.com>,
	Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de>,
	Stephen Boyd <sboyd@codeaurora.org>
Subject: Re: [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk
Date: Sat, 22 Feb 2014 23:30:19 +0100	[thread overview]
Message-ID: <20140222223019.GB20490@amd.pavel.ucw.cz> (raw)
In-Reply-To: <20140222101655.GE21483@n2100.arm.linux.org.uk>

On Sat 2014-02-22 10:16:55, Russell King - ARM Linux wrote:
> On Thu, Feb 20, 2014 at 04:27:55PM +0000, Lorenzo Pieralisi wrote:
> > I still do not understand why switching to idmap, which is a clone of
> > init_mm + 1:1 kernel mappings is required here. Why idmap ?
> > 
> > And while at it, can't the idmap be overwritten _while_ copying back the
> > resume kernel ? Is it safe to use idmap page tables while copying ?
> > 
> > I had a look at x86 and there idmap page tables used to resume are created
> > on the fly using safe pages, on ARM idmap is created at boot.
> 
> That's fine.
> 
> Remember, you're required to boot exactly the same kernel image when
> resuming as the kernel which created the suspend image.  Unless you
> have random allocations going on, you should get the same layout for
> the idmap stuff at each boot.

Actually, x86-64 is able to resume from different kernel these days,
and some day you may want to do it on arm, too. But it is definitely
not needed for inital merge.

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

WARNING: multiple messages have this Message-ID (diff)
From: pavel@ucw.cz (Pavel Machek)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk
Date: Sat, 22 Feb 2014 23:30:19 +0100	[thread overview]
Message-ID: <20140222223019.GB20490@amd.pavel.ucw.cz> (raw)
In-Reply-To: <20140222101655.GE21483@n2100.arm.linux.org.uk>

On Sat 2014-02-22 10:16:55, Russell King - ARM Linux wrote:
> On Thu, Feb 20, 2014 at 04:27:55PM +0000, Lorenzo Pieralisi wrote:
> > I still do not understand why switching to idmap, which is a clone of
> > init_mm + 1:1 kernel mappings is required here. Why idmap ?
> > 
> > And while at it, can't the idmap be overwritten _while_ copying back the
> > resume kernel ? Is it safe to use idmap page tables while copying ?
> > 
> > I had a look at x86 and there idmap page tables used to resume are created
> > on the fly using safe pages, on ARM idmap is created at boot.
> 
> That's fine.
> 
> Remember, you're required to boot exactly the same kernel image when
> resuming as the kernel which created the suspend image.  Unless you
> have random allocations going on, you should get the same layout for
> the idmap stuff at each boot.

Actually, x86-64 is able to resume from different kernel these days,
and some day you may want to do it on arm, too. But it is definitely
not needed for inital merge.

Thanks,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

  parent reply	other threads:[~2014-02-22 22:30 UTC|newest]

Thread overview: 91+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-02-19  1:52 [PATCH RFC v1 0/3] hibernation support on ARM Sebastian Capella
2014-02-19  1:52 ` Sebastian Capella
2014-02-19  1:52 ` [PATCH RFC v1 1/3] ARM: Add irq disabled version of soft_restart Sebastian Capella
2014-02-19  1:52   ` Sebastian Capella
2014-02-22 10:26   ` Russell King - ARM Linux
2014-02-22 10:26     ` Russell King - ARM Linux
2014-02-24 23:13     ` Sebastian Capella
2014-02-24 23:13       ` Sebastian Capella
2014-02-25  0:22       ` Sebastian Capella
2014-02-25  0:22         ` Sebastian Capella
2014-02-25  7:56       ` Russ Dill
2014-02-25  7:56         ` Russ Dill
2014-02-25  7:56         ` Russ Dill
2014-02-25 10:27         ` Thomas Gleixner
2014-02-25 10:27           ` Thomas Gleixner
2014-02-25 17:15           ` Russ Dill
2014-02-25 17:15             ` Russ Dill
2014-02-25 17:15             ` Russ Dill
2014-02-25 23:24             ` Sebastian Capella
2014-02-25 23:24               ` Sebastian Capella
2014-02-19  1:52 ` [PATCH RFC v1 2/3] Fix hibernation restore hang in freeze_processes Sebastian Capella
2014-02-19  1:52   ` Sebastian Capella
2014-02-24  7:09   ` Ming Lei
2014-02-24  7:09     ` Ming Lei
2014-02-19  1:52 ` [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk Sebastian Capella
2014-02-19  1:52   ` Sebastian Capella
2014-02-19 16:12   ` Lorenzo Pieralisi
2014-02-19 16:12     ` Lorenzo Pieralisi
2014-02-19 16:12     ` Lorenzo Pieralisi
2014-02-19 19:10     ` Russ Dill
2014-02-19 19:10       ` Russ Dill
2014-02-19 19:10       ` Russ Dill
2014-02-20 10:37       ` Lorenzo Pieralisi
2014-02-20 10:37         ` Lorenzo Pieralisi
2014-02-20 10:37         ` Lorenzo Pieralisi
2014-02-19 19:33     ` Sebastian Capella
2014-02-19 19:33       ` Sebastian Capella
2014-02-20 16:27       ` Lorenzo Pieralisi
2014-02-20 16:27         ` Lorenzo Pieralisi
2014-02-20 16:27         ` Lorenzo Pieralisi
2014-02-21 18:39         ` Sebastian Capella
2014-02-21 18:39           ` Sebastian Capella
2014-02-21 23:59           ` Sebastian Capella
2014-02-21 23:59             ` Sebastian Capella
2014-02-22  4:37             ` Sebastian Capella
2014-02-22  4:37               ` Sebastian Capella
2014-02-22  6:46               ` Russ Dill
2014-02-22  6:46                 ` Russ Dill
2014-02-22  6:46                 ` Russ Dill
2014-02-22 10:22                 ` Russell King - ARM Linux
2014-02-22 10:22                   ` Russell King - ARM Linux
2014-02-22 10:22                   ` Russell King - ARM Linux
2014-02-22 10:16         ` Russell King - ARM Linux
2014-02-22 10:16           ` Russell King - ARM Linux
2014-02-22 10:16           ` Russell King - ARM Linux
2014-02-22 12:13           ` Lorenzo Pieralisi
2014-02-22 12:13             ` Lorenzo Pieralisi
2014-02-22 12:13             ` Lorenzo Pieralisi
2014-02-22 22:30           ` Pavel Machek [this message]
2014-02-22 22:30             ` Pavel Machek
2014-02-22 22:30             ` Pavel Machek
2014-02-21  1:01     ` Sebastian Capella
2014-02-21  1:01       ` Sebastian Capella
2014-02-22 10:38     ` Russell King - ARM Linux
2014-02-22 10:38       ` Russell King - ARM Linux
2014-02-22 10:38       ` Russell King - ARM Linux
2014-02-22 12:09       ` Lorenzo Pieralisi
2014-02-22 12:09         ` Lorenzo Pieralisi
2014-02-22 12:09         ` Lorenzo Pieralisi
2014-02-22 22:28         ` Pavel Machek
2014-02-22 22:28           ` Pavel Machek
2014-02-22 22:28           ` Pavel Machek
2014-02-23 19:52         ` Sebastian Capella
2014-02-23 19:52           ` Sebastian Capella
2014-02-23 19:52           ` Sebastian Capella
2014-02-23 20:02         ` Sebastian Capella
2014-02-23 20:02           ` Sebastian Capella
2014-02-23 20:02           ` Sebastian Capella
2014-02-25 11:32           ` Lorenzo Pieralisi
2014-02-25 11:32             ` Lorenzo Pieralisi
2014-02-25 11:32             ` Lorenzo Pieralisi
2014-02-25 17:55             ` Sebastian Capella
2014-02-25 17:55               ` Sebastian Capella
2014-02-26 10:24               ` Lorenzo Pieralisi
2014-02-26 10:24                 ` Lorenzo Pieralisi
2014-02-26 10:24                 ` Lorenzo Pieralisi
2014-02-26 17:50                 ` Sebastian Capella
2014-02-26 17:50                   ` Sebastian Capella
2014-02-26 19:03                   ` Lorenzo Pieralisi
2014-02-26 19:03                     ` Lorenzo Pieralisi
2014-02-26 19:03                     ` Lorenzo Pieralisi

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20140222223019.GB20490@amd.pavel.ucw.cz \
    --to=pavel@ucw.cz \
    --cc=Catalin.Marinas@arm.com \
    --cc=Jonathan.Austin@arm.com \
    --cc=Russ.Dill@ti.com \
    --cc=Will.Deacon@arm.com \
    --cc=cyril@ti.com \
    --cc=len.brown@intel.com \
    --cc=linaro-kernel@lists.linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=linux@arm.linux.org.uk \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=nico@linaro.org \
    --cc=rjw@rjwysocki.net \
    --cc=santosh.shilimkar@ti.com \
    --cc=sboyd@codeaurora.org \
    --cc=sebastian.capella@linaro.org \
    --cc=u.kleine-koenig@pengutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.