[PATCH initramfs-tools 4/9] initramfs.conf(5): Document the RESUME variable

[Ben Hutchings]

It's already mentioned in other manual pages, but not in the most obvious one.

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
initramfs.conf.5 | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/initramfs.conf.5 b/initramfs.conf.5
index 184001ca98c2..4d142dd0950a 100644
--- a/initramfs.conf.5
+++ b/initramfs.conf.5
@@ -74,6 +74,14 @@ Allows one to use an nfs drive as the root of the drive.
The default is to boot from \fIlocal\fP media (hard drive, USB stick).
Set to \fInfs\fP for an NFS root share.

+.SH VARIABLES FOR LOCAL BOOT
+.TP
+\fB RESUME
+Specifies the device used for suspend-to-disk (hibernation), which the
+initramfs code should attempt to resume from. If this is not defined,
+.B mkinitramfs
+will automatically select the largest available swap partition.
+
.SH VARIABLES FOR NFS BOOT
.TP
\fB DEVICE

[Ben Hutchings]

The change in version 0.128 to wait for the resume device to appear
uncovered a number of systems for which the resume device is not
properly configured. In fact, systems with swap partitions that
are never available at boot could not be configured correctly,
other than by adding 'noresume' to the kernel command line!

While working on that, I found and fixed a couple of other
longstanding bugs in resume device selection.

This patch series:

- Fixes the sorting of swap partitions
- Makes the RESUME variable work like every other configuration
variable, and documents it
- Adds support for RESUME=none (disable resume) and RESUME=auto
(explicitly request automatic selection)
- Adds warning and informational messages where the resume device
configuration is automatically fixed-up

I'm stil not entirely happy with the automatic resume device
selection. I would prefer to read the kernel's selection from
/sys/power/resume, but I found experimentally that this isn't set on a
fresh boot under older kernel versions. Secondly I would like to
automatically filter out device types that we know won't be
available at boot (e.g. zram). But I think this may have to do.

If no-one finds issues with this these changes then I'm hoping
to make one more release for "stretch" with just these.

Ben.

Ben Hutchings (9):
hooks/resume: Use correct sort options to select the biggest swap
partition
initramfs.conf(5): Clean up split between general and NFS variables
Support setting of RESUME in initramfs.conf or anywhere in conf.d/
initramfs.conf(5): Document the RESUME variable
hooks/resume: Check for chroot earlier
Allow disabling resume from disk at build time by setting RESUME=none
Support requesting automatic selection of resume device with
RESUME=auto
hooks/resume: Report when we might be doing something surprising
NEWS: Add entry explaining the need for RESUME=none on some systems

debian/NEWS | 21 +++++++++++++++++++++
hooks/resume | 54 ++++++++++++++++++++++++++++++++++++------------------
init | 4 ++--
initramfs.conf.5 | 12 +++++++++++-
mkinitramfs | 1 +
5 files changed, 71 insertions(+), 21 deletions(-)

[Ben Hutchings]

The BOOT variable selects between local and NFS mode, so it's not
really an NFS-specific variable.

Also reword the section heading.

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

initramfs.conf.5 | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/initramfs.conf.5 b/initramfs.conf.5
index 7eee859897bf..184001ca98c2 100644
--- a/initramfs.conf.5
+++ b/initramfs.conf.5
@@ -68,13 +68,13 @@ corresponding userspace utility is not present.
Set the umask value of the generated initramfs file.
Useful to not disclose eventual keys.

-.SH NFS VARIABLES
.TP
\fB BOOT

Allows one to use an nfs drive as the root of the drive.
The default is to boot from \fIlocal\fP media (hard drive, USB stick).
Set to \fInfs\fP for an NFS root share.

+.SH VARIABLES FOR NFS BOOT
.TP
\fB DEVICE
Specifies the network interface, like eth0.

[Ben Hutchings]

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 3 ++-
init | 4 ++--
initramfs.conf.5 | 1 +
3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/hooks/resume b/hooks/resume
index e8a49124c3f9..3e3f6dbbc3b6 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -16,7 +16,8 @@ prereqs)
esac

# First check if a location is set and is a valid swap partition
-if [ -n "$RESUME" ] && blkid -p -n swap $RESUME >/dev/null 2>&1; then
+if [ -n "$RESUME" ] && \
+ { [ "$RESUME" = none ] || blkid -p -n swap $RESUME >/dev/null 2>&1; }; then
# As mkinitramfs copies the config file nothing to do.
exit 0
fi
diff --git a/init b/init
index 9552e5cab9c0..1334dca6a99d 100755
--- a/init
+++ b/init
@@ -189,8 +189,8 @@ if [ -z "${BOOT}" ]; then
BOOT=local
fi

-if [ -n "${noresume}" ]; then
- export noresume
+if [ -n "${noresume}" ] || [ "$RESUME" = none ]; then
+ export noresume=y
unset resume
else
resume=${RESUME:-}
diff --git a/initramfs.conf.5 b/initramfs.conf.5
index 4d142dd0950a..c0d778ca1928 100644
--- a/initramfs.conf.5
+++ b/initramfs.conf.5
@@ -81,6 +81,7 @@ Specifies the device used for suspend-to-disk (hibernation), which the

initramfs code should attempt to resume from. If this is not defined,

.B mkinitramfs

will automatically select the largest available swap partition.

+Set it to \fInone\fP to disable resume from disk.

[Ben Hutchings]

Currently hooks/resume only reads /etc/initramfs-tools/conf.d/resume,
whereas at boot time it can be set by any configuration file.
Instead, export RESUME from mkinitramfs, which reads all the
configuration files.

When writing an auto-selected resume device, use a filename that
should sort later than user configuration files (zz-resume-auto).

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 6 ++----
mkinitramfs | 1 +
2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/hooks/resume b/hooks/resume
index c43badd03f71..d5a987602787 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -16,8 +16,6 @@ prereqs)

esac

# First check if a location is set and is a valid swap partition

-test -r /etc/initramfs-tools/conf.d/resume \
- && . /etc/initramfs-tools/conf.d/resume

if [ -n "$RESUME" ] && blkid -p -n swap $RESUME >/dev/null 2>&1; then

# As mkinitramfs copies the config file nothing to do.
exit 0

@@ -37,7 +35,7 @@ if [ -n "$RESUME" ]; then
fi
fi

-# Write detected resume to intramfs conf.d/resume if not in a chroot
+# Write detected resume to intramfs conf.d if not in a chroot
if [ -n "${RESUME}" ] && ! ischroot; then
- echo "RESUME=${RESUME}" > ${DESTDIR}/conf/conf.d/resume
+ echo "RESUME=${RESUME}" > ${DESTDIR}/conf/conf.d/zz-resume-auto
fi
diff --git a/mkinitramfs b/mkinitramfs
index 9f207a0a00df..24715d5e5287 100755
--- a/mkinitramfs
+++ b/mkinitramfs
@@ -205,6 +205,7 @@ export verbose
export KEYMAP
export MODULES
export BUSYBOX
+export RESUME

# Private, used by 'catenate_cpiogz'.
export __TMPCPIOGZ

[Ben Hutchings]

For now, this is effectively the same as setting RESUME to empty or
not setting it.

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 25 ++++++++++++++-----------
initramfs.conf.5 | 3 ++-
2 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/hooks/resume b/hooks/resume
index 3e3f6dbbc3b6..43eb146b1f42 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -16,7 +16,7 @@ prereqs)

esac

# First check if a location is set and is a valid swap partition

-if [ -n "$RESUME" ] && \
+if [ -n "$RESUME" ] && [ "$RESUME" != auto ] && \
{ [ "$RESUME" = none ] || blkid -p -n swap $RESUME >/dev/null 2>&1; }; then

# As mkinitramfs copies the config file nothing to do.
exit 0

@@ -24,16 +24,19 @@ fi

# We need to be able to read the listed swap partitions
if ischroot || [ ! -r /proc/swaps ]; then
- exit 0
+ resume_auto=
+else
+ # Try to autodetect the RESUME partition, using biggest swap?
+ resume_auto=$(grep ^/dev/ /proc/swaps | sort -rnk3 | head -n 1 | cut -d " " -f 1)
+ if [ -n "$resume_auto" ]; then
+ UUID=$(blkid -s UUID -o value "$resume_auto" || true)
+ if [ -n "$UUID" ]; then
+ resume_auto="UUID=$UUID"
+ fi
+ fi
fi

-# Try to autodetect the RESUME partition, using biggest swap?

-# Write detected resume to intramfs conf.d

-RESUME=$(grep ^/dev/ /proc/swaps | sort -rnk3 | head -n 1 | cut -d " " -f 1)
-if [ -n "$RESUME" ]; then
- UUID=$(blkid -s UUID -o value "$RESUME" || true)
- if [ -n "$UUID" ]; then
- RESUME="UUID=$UUID"
- fi
- echo "RESUME=${RESUME}" > ${DESTDIR}/conf/conf.d/zz-resume-auto
+# Write selected resume device to intramfs conf.d
+if [ "$RESUME" = auto ] || [ -n "$resume_auto" ]; then
+ echo "RESUME=${resume_auto}" > ${DESTDIR}/conf/conf.d/zz-resume-auto
fi
diff --git a/initramfs.conf.5 b/initramfs.conf.5
index c0d778ca1928..b4eea705016f 100644
--- a/initramfs.conf.5
+++ b/initramfs.conf.5
@@ -78,7 +78,8 @@ Set to \fInfs\fP for an NFS root share.
.TP
\fB RESUME

Specifies the device used for suspend-to-disk (hibernation), which the

-initramfs code should attempt to resume from. If this is not defined,
+initramfs code should attempt to resume from. If this is not defined
+or is set to \fIauto\fP,

.B mkinitramfs
will automatically select the largest available swap partition.

[Ben Hutchings]

We need a reverse *numeric* sort.

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 2 +-

1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hooks/resume b/hooks/resume
index 657775e4a465..c43badd03f71 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -29,7 +29,7 @@ if [ ! -r /proc/swaps ]; then
fi

# Try to autodetect the RESUME partition, using biggest swap?

-RESUME=$(grep ^/dev/ /proc/swaps | sort -rk3 | head -n 1 | cut -d " " -f 1)
+RESUME=$(grep ^/dev/ /proc/swaps | sort -rnk3 | head -n 1 | cut -d " " -f 1)
if [ -n "$RESUME" ]; then

UUID=$(blkid -s UUID -o value "$RESUME" || true)

if [ -n "$UUID" ]; then

[Ben Hutchings]

Avoid doing unnecessary work.

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/hooks/resume b/hooks/resume
index d5a987602787..e8a49124c3f9 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -22,20 +22,17 @@ if [ -n "$RESUME" ] && blkid -p -n swap $RESUME >/dev/null 2>&1; then

fi

# We need to be able to read the listed swap partitions

-if [ ! -r /proc/swaps ]; then
+if ischroot || [ ! -r /proc/swaps ]; then
exit 0

fi

# Try to autodetect the RESUME partition, using biggest swap?

+# Write detected resume to intramfs conf.d

RESUME=$(grep ^/dev/ /proc/swaps | sort -rnk3 | head -n 1 | cut -d " " -f 1)
if [ -n "$RESUME" ]; then
UUID=$(blkid -s UUID -o value "$RESUME" || true)
if [ -n "$UUID" ]; then

RESUME="UUID=$UUID"
fi
-fi
-
-# Write detected resume to intramfs conf.d if not in a chroot
-if [ -n "${RESUME}" ] && ! ischroot; then

echo "RESUME=${RESUME}" > ${DESTDIR}/conf/conf.d/zz-resume-auto

fi

[Ben Hutchings]

Closes: #860403

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

debian/NEWS | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/debian/NEWS b/debian/NEWS
index e862c6144ba9..78a0c6856edc 100644
--- a/debian/NEWS
+++ b/debian/NEWS
@@ -1,3 +1,24 @@
+initramfs-tools (0.129) unstable; urgency=medium
+
+ * Some systems that do not support suspend-to-disk (hibernation) will
+ require a configuration change to explicitly disable this.
+
+ From version 0.128, the boot code waits for a suspend/resume device
+ to appear, rather than checking just once. If the configured or
+ automatically selected resume device is not available at boot time,
+ this results in a roughly 30 second delay.
+
+ You should set the RESUME variable in
+ /etc/initramfs-tools/conf.d/resume or
+ /etc/initramfs-tools/initramfs.conf to one of:
+
+ - auto - select the resume device automatically
+ - none - disable use of a resume device
+ - UUID=<uuid> - use a specific resume device (by UUID)
+ - /dev/<name> - use a specific resume device (by kernel name)
+
+ -- Ben Hutchings <b...@decadent.org.uk> Thu, 20 Apr 2017 23:21:32 +0100
+
initramfs-tools (0.121~rc1) unstable; urgency=medium

* If initramfs-tools is configured to use busybox but it is not

[Ben Hutchings]

Some systems have swap devices that aren't available at boot, but are
still selected as resume devices. There used to be no way to disable
this at build time, but it also used to be quite harmless. Now that
we wait for the resume device to appear, this is a real problem and
users of such systems will need to set RESUME=none. Therefore:

- If RESUME is invalid, warn about this
- If RESUME is unset or invalid, and we automatically set a resume device,
report this

Also:

- If RESUME=auto and we we fail to select a resume device, warn about
this

Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---

hooks/resume | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/hooks/resume b/hooks/resume
index 43eb146b1f42..06ff62af3f3c 100755
--- a/hooks/resume
+++ b/hooks/resume
@@ -16,12 +16,23 @@ prereqs)

esac

# First check if a location is set and is a valid swap partition

-if [ -n "$RESUME" ] && [ "$RESUME" != auto ] && \
- { [ "$RESUME" = none ] || blkid -p -n swap $RESUME >/dev/null 2>&1; }; then
- # As mkinitramfs copies the config file nothing to do.
- exit 0
+if [ -n "$RESUME" ] && [ "$RESUME" != auto ]; then
+ if [ "$RESUME" = none ] || blkid -p -n swap $RESUME >/dev/null 2>&1; then
+ # As mkinitramfs copies the config file nothing to do.
+ exit 0
+ fi
+
+ echo >&2 "W: initramfs-tools configuration sets RESUME=$RESUME"
+ echo >&2 "W: but no matching swap device is available."
fi

+# If we were not explicitly requested to select a device, report that we
+# are doing so
+report_auto()
+{
+ test "$RESUME" = auto || echo >&2 "I: $*"
+}
+

# We need to be able to read the listed swap partitions

if ischroot || [ ! -r /proc/swaps ]; then

resume_auto=
@@ -30,13 +41,21 @@ else
resume_auto=$(grep ^/dev/ /proc/swaps | sort -rnk3 | head -n 1 | cut -d " " -f 1)
if [ -n "$resume_auto" ]; then
UUID=$(blkid -s UUID -o value "$resume_auto" || true)
+ report_auto "The initramfs will attempt to resume from $resume_auto"
if [ -n "$UUID" ]; then
+ report_auto "(UUID=$UUID)"
resume_auto="UUID=$UUID"
fi
+ report_auto "Set the RESUME variable to override this."
fi
fi

# Write selected resume device to intramfs conf.d

if [ "$RESUME" = auto ] || [ -n "$resume_auto" ]; then

+ # If we were explicitly requested to select a device, and we failed,
+ # report that
+ if [ -z "$resume_auto" ]; then
+ echo >&2 "W: initramfs-tools failed to select a resume device"
+ fi

[Martin Steigerwald]

Dear Ben.

Ben Hutchings - 21.04.17, 04:33:

> The change in version 0.128 to wait for the resume device to appear
> uncovered a number of systems for which the resume device is not
> properly configured. In fact, systems with swap partitions that
> are never available at boot could not be configured correctly,
> other than by adding 'noresume' to the kernel command line!
>
> While working on that, I found and fixed a couple of other
> longstanding bugs in resume device selection.
>
> This patch series:
>
> - Fixes the sorting of swap partitions
> - Makes the RESUME variable work like every other configuration
> variable, and documents it
> - Adds support for RESUME=none (disable resume) and RESUME=auto
> (explicitly request automatic selection)
> - Adds warning and informational messages where the resume device
> configuration is automatically fixed-up

Thats interesting. I have an old ThinkPad T42 above my hi-fi equipment as a
media player and it stopped resuming from hibernation after some update quite
some time ago. But instead it just boots as if there would be no hibernation
image. On hibernation it actually does write the hibernation image – I use in
kernel hibernation, not userspace software suspend, but I think I tried using
that one as well. Currently I don´t have uswsusp installed, but pm-utils is
still there. I am not sure whether systemd uses it or does it all by itself
tough. I configured in-kernel suspend there as well:

shambhala:/etc/pm> cat ./config.d/sleepmodule.conf
SLEEP_MODULE=kernel

Currently initramfs-tools is at 0.127 on this not so regularily updated
laptop.


I never managed to get around actually looking whats going on here, but I now
found that I do not have any resume setting in

shambhala:/etc/initramfs-tools> grep -ir "RESUME" .
shambhala:/etc/initramfs-tools#1>

Instead I have it here:

shambhala:/etc/default> grep -i resume grub
GRUB_CMDLINE_LINUX_DEFAULT="resume=/dev/sda2 init=/bin/systemd"


shambhala:~> swapon -s
Dateiname Typ Größe Benutzt
Priorität
/dev/sda2 partition 4000180 0 -1

shambhala:~> lsblk /dev/sda2
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda2 8:2 0 3,8G 0 part [SWAP]
shambhala:~> LANG=C swapon -s
Filename Type Size Used
Priority
/dev/sda2 partition 4000180 0 -1


Okay, I will upgrade to the new initramfs-tools and look whether it fixes the
issue. If not, I may try setting RESUME var to first "auto" and if not working
still then the device in question to see whether that helps. I welcome any
other ideas and I am willing to report back what I find.

Ciao,
--
Martin

[Michael Prokop]

* Ben Hutchings [Fri Apr 21, 2017 at 04:33:09AM +0100]:

> The change in version 0.128 to wait for the resume device to appear
> uncovered a number of systems for which the resume device is not
> properly configured. In fact, systems with swap partitions that
> are never available at boot could not be configured correctly,
> other than by adding 'noresume' to the kernel command line!

> While working on that, I found and fixed a couple of other
> longstanding bugs in resume device selection.

[...]

> If no-one finds issues with this these changes then I'm hoping
> to make one more release for "stretch" with just these.

The changes LGTM (I didn't test/verify them though).
Thanks, Ben.

regards,
-mika-

[Ben Hutchings]

On Fri, 2017-04-21 at 11:02 +0200, Martin Steigerwald wrote:
[...]

> Currently I don´t have uswsusp installed, but pm-utils is 
> still there. I am not sure whether systemd uses it or does it all by itself 
> tough.

I think 'systemctl hibernate' invokes in-kernel swsusp by default. I
don't know what pm-utils does.

[...]

> I never managed to get around actually looking whats going on here, but I now 
> found that I do not have any resume setting in
>
> shambhala:/etc/initramfs-tools> grep -ir "RESUME" .
> shambhala:/etc/initramfs-tools#1>

So initramfs-tools will automatically select a swap partition and put
its UUID in the initramfs...

> Instead I have it here:
>
> shambhala:/etc/default> grep -i resume grub
> GRUB_CMDLINE_LINUX_DEFAULT="resume=/dev/sda2 init=/bin/systemd"

...but the command line parameter overrides that configuration, anyway.

> shambhala:~> swapon -s
> Dateiname                               Typ             Größe   Benutzt 
> Priorität
> /dev/sda2                               partition       4000180 0       -1
>
> shambhala:~> lsblk /dev/sda2
> NAME MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
> sda2   8:2    0  3,8G  0 part [SWAP]
> shambhala:~> LANG=C swapon -s
> Filename                                Type            Size    Used    
> Priority
> /dev/sda2                               partition       4000180 0       -1
>
>
> Okay, I will upgrade to the new initramfs-tools and look whether it fixes the 
> issue.

I think that the changes in 0.128 - to wait for the resume device to
appear - may fix this problem. The changes I've posted here shouldn't
make any difference for your configuration.

> If not, I may try setting RESUME var to first "auto" and if not working 
> still then the device in question to see whether that helps. I welcome any 
> other ideas and I am willing to report back what I find.

RESUME=auto isn't supported in a released version.

Ben.

--
Ben Hutchings
I'm not a reverse psychological virus.  Please don't copy me into your
sig.

[Bjørn Mork]

Ben Hutchings <b...@decadent.org.uk> writes:

> The change in version 0.128 to wait for the resume device to appear
> uncovered a number of systems for which the resume device is not
> properly configured. In fact, systems with swap partitions that
> are never available at boot could not be configured correctly,
> other than by adding 'noresume' to the kernel command line!
>
> While working on that, I found and fixed a couple of other
> longstanding bugs in resume device selection.
>
> This patch series:
>
> - Fixes the sorting of swap partitions
> - Makes the RESUME variable work like every other configuration
> variable, and documents it
> - Adds support for RESUME=none (disable resume) and RESUME=auto
> (explicitly request automatic selection)
> - Adds warning and informational messages where the resume device
> configuration is automatically fixed-up

Hmm, I got this warning, which seems harmless but unexpected:

Processing triggers for initramfs-tools (0.129) ...
update-initramfs: Generating /boot/initrd.img-4.9.0-2-amd64
W: initramfs-tools configuration sets RESUME=UUID=30db89e8-91f2-44ee-a8fa-61e5855ead41

W: but no matching swap device is available.

I: The initramfs will attempt to resume from /dev/nvme0n1p4
I: (UUID=30db89e8-91f2-44ee-a8fa-61e5855ead41)
I: Set the RESUME variable to override this.



My swap/resume settings are:


bjorn@miraculix:~$ cat /proc/swaps

Filename Type Size Used Priority

/dev/nvme0n1p4 partition 16424956 1119612 -1
bjorn@miraculix:~$ cat /etc/initramfs-tools/conf.d/resume
RESUME=UUID=30db89e8-91f2-44ee-a8fa-61e5855ead41
bjorn@miraculix:~$ file -s /dev/nvme0n1p4
/dev/nvme0n1p4: no read permission
bjorn@miraculix:~$ ls -l /dev/disk/by-uuid/
total 0
lrwxrwxrwx 1 root root 15 Mar 23 19:22 30db89e8-91f2-44ee-a8fa-61e5855ead41 -> ../../nvme0n1p4
lrwxrwxrwx 1 root root 15 Mar 23 19:22 71507198-90f4-4c25-be41-efc47d2dedd1 -> ../../nvme0n1p3
lrwxrwxrwx 1 root root 15 Mar 23 19:22 DA5D-17DD -> ../../nvme0n1p1



Bjørn

[Ben Hutchings]

[...]

This is bug #861057 which should be fixed now.

Ben.

--
Ben Hutchings
All extremists should be taken out and shot.