From: jfannin@gmail.com (Joseph Fannin)
To: Oliver Neukum <oliver@neukum.org>
Cc: Joseph Fannin <jfannin@gmail.com>,
Jeremy Maitin-Shepard <jbms@cmu.edu>,
david@lang.hm, "Rafael J. Wysocki" <rjw@sisk.pl>,
"Huang, Ying" <ying.huang@intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Pavel Machek <pavel@ucw.cz>,
nigel@nigel.suspend2.net, linux-kernel@vger.kernel.org,
linux-pm@lists.linux-foundation.org
Subject: Re: Hibernating To Swap Considered Harmful
Date: Tue, 17 Jul 2007 02:28:03 -0400 [thread overview]
Message-ID: <20070717062803.GA9069@nineveh.local> (raw)
In-Reply-To: <200707170744.08191.oliver@neukum.org>
On Tue, Jul 17, 2007 at 07:44:07AM +0200, Oliver Neukum wrote:
>
> If yoi want to go the kexec route to hibernation, the dumping kernel
> would need to mount the filesystem to write to a file. Therefore the
> suspending kernel would need to sync to disk and lock that file.
If the file is preallocated, that's not a problem, as there's no need
to touch filesystem metadata. There'd need to be some channel to pass
the disk blocks that are for writing the image, but that's not going
to be nearly as complicated as passing the current swap data
structures from the previous kernel.
There's no reason to have that file open in the original kernel --
it should be root-owned (it's full of privledged data) and probably
mode 000.
root is free to "dd if=/dev/random of=/dev/mem". Root owned
daemons which do bad things are bugs.
Again, supporting swap files (*which is not optional*) requires the
very same support.
--
Joseph Fannin
jfannin@gmail.com
next prev parent reply other threads:[~2007-07-17 6:28 UTC|newest]
Thread overview: 121+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-07-11 15:30 [PATCH 0/2] Kexec jump: The first step to kexec base hibernation Huang, Ying
2007-07-11 11:13 ` Pavel Machek
2007-07-12 16:28 ` Huang, Ying
2007-07-12 8:54 ` Pavel Machek
2007-07-13 23:18 ` Huang, Ying
2007-07-12 0:22 ` Andrew Morton
2007-07-12 5:48 ` Jeremy Fitzhardinge
2007-07-12 6:43 ` david
2007-07-12 12:46 ` Rafael J. Wysocki
2007-07-12 13:51 ` Mark Lord
2007-07-12 14:49 ` Pavel Machek
2007-07-12 15:35 ` Rafael J. Wysocki
2007-07-12 16:03 ` Mark Lord
2007-07-12 16:35 ` Mark Lord
2007-07-12 20:05 ` Jeremy Maitin-Shepard
2007-07-13 2:38 ` Mark Lord
2007-07-12 16:09 ` [linux-pm] " Alan Stern
2007-07-12 18:49 ` david
2007-07-12 18:42 ` david
2007-07-12 19:20 ` Rafael J. Wysocki
2007-07-12 19:14 ` david
2007-07-12 19:45 ` Rafael J. Wysocki
2007-07-12 17:09 ` Huang, Ying
2007-07-12 12:47 ` Rafael J. Wysocki
2007-07-12 12:38 ` Rafael J. Wysocki
2007-07-12 14:43 ` Huang, Ying
2007-07-12 7:03 ` david
2007-07-12 17:18 ` Huang, Ying
2007-07-12 10:10 ` david
2007-07-12 13:01 ` Rafael J. Wysocki
2007-07-12 13:22 ` jimmy bahuleyan
2007-07-12 19:03 ` david
2007-07-12 13:55 ` Mark Lord
2007-07-12 19:05 ` david
2007-07-12 14:06 ` Pavel Machek
2007-07-12 12:53 ` Rafael J. Wysocki
2007-07-12 18:57 ` david
2007-07-12 19:34 ` Rafael J. Wysocki
2007-07-12 19:55 ` Jeremy Maitin-Shepard
2007-07-12 20:45 ` Rafael J. Wysocki
2007-07-13 3:12 ` david
2007-07-13 9:17 ` Rafael J. Wysocki
2007-07-13 9:25 ` david
2007-07-13 11:41 ` Rafael J. Wysocki
2007-07-14 7:51 ` david
2007-07-14 8:33 ` david
2007-07-14 9:24 ` Rafael J. Wysocki
2007-07-14 20:00 ` Rafael J. Wysocki
2007-07-14 20:34 ` david
2007-07-14 21:06 ` Rafael J. Wysocki
2007-07-14 21:13 ` david
2007-07-15 10:31 ` Rafael J. Wysocki
2007-07-15 19:23 ` david
2007-07-15 22:59 ` Rafael J. Wysocki
2007-07-15 23:22 ` david
2007-07-16 12:17 ` Rafael J. Wysocki
2007-07-16 14:42 ` Huang, Ying
2007-07-16 15:40 ` Rafael J. Wysocki
2007-07-17 4:18 ` david
2007-07-17 11:46 ` Rafael J. Wysocki
2007-07-14 21:34 ` david
2007-07-15 10:39 ` Rafael J. Wysocki
2007-07-15 19:33 ` david
2007-07-15 23:11 ` Rafael J. Wysocki
2007-07-15 23:33 ` david
2007-07-13 3:06 ` david
2007-07-13 5:42 ` Hibernating To Swap Considered Harmful Joseph Fannin
2007-07-13 5:57 ` david
2007-07-13 6:20 ` Joseph Fannin
2007-07-13 6:27 ` david
2007-07-13 7:15 ` Joseph Fannin
2007-07-13 14:35 ` Jeremy Maitin-Shepard
2007-07-17 0:12 ` Joseph Fannin
2007-07-17 5:44 ` Oliver Neukum
2007-07-17 6:28 ` Joseph Fannin [this message]
2007-07-17 6:42 ` david
2007-07-17 7:26 ` Joseph Fannin
2007-07-17 7:34 ` david
2007-07-17 11:54 ` Rafael J. Wysocki
2007-07-17 11:52 ` Rafael J. Wysocki
2007-07-17 7:10 ` Oliver Neukum
2007-07-13 9:30 ` Rafael J. Wysocki
2007-07-14 0:45 ` Joseph Fannin
2007-07-14 9:48 ` Rafael J. Wysocki
2007-07-16 5:37 ` Joseph Fannin
2007-07-13 9:29 ` [PATCH 0/2] Kexec jump: The first step to kexec base hibernation Rafael J. Wysocki
2007-07-13 9:38 ` david
2007-07-13 11:59 ` Rafael J. Wysocki
2007-07-13 14:37 ` [linux-pm] " Alan Stern
2007-07-13 15:31 ` Rafael J. Wysocki
2007-07-14 7:13 ` david
2007-07-13 15:12 ` Jeremy Maitin-Shepard
2007-07-13 15:45 ` Rafael J. Wysocki
2007-07-13 15:50 ` Alan Stern
2007-07-13 16:54 ` Eric W. Biederman
2007-07-13 18:15 ` Alan Stern
2007-07-13 21:08 ` Rafael J. Wysocki
2007-07-13 20:55 ` Rafael J. Wysocki
2007-07-13 16:48 ` Jeremy Maitin-Shepard
2007-07-13 21:23 ` Rafael J. Wysocki
2007-07-14 7:12 ` david
2007-07-13 17:32 ` Huang, Ying
2007-07-13 12:01 ` Rafael J. Wysocki
2007-07-12 16:32 ` Eric W. Biederman
2007-07-12 19:09 ` david
2007-07-12 19:49 ` Eric W. Biederman
2007-07-13 23:15 ` Huang, Ying
2007-07-13 16:43 ` Eric W. Biederman
2007-07-14 5:48 ` Huang, Ying
2007-07-14 9:59 ` Rafael J. Wysocki
2007-07-14 10:55 ` Huang, Ying
2007-07-14 19:16 ` Rafael J. Wysocki
2007-07-15 9:30 ` Huang, Ying
2007-07-15 10:49 ` Rafael J. Wysocki
2007-07-24 14:00 ` Huang, Ying
2007-07-24 15:27 ` Rafael J. Wysocki
2007-07-17 8:13 ` david
2007-07-17 11:59 ` Rafael J. Wysocki
2007-07-17 12:48 ` Huang, Ying
2007-07-17 14:22 ` Rafael J. Wysocki
2007-07-18 0:25 ` david
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