Commit Graph

10 Commits

Author SHA1 Message Date
Steffen Maier
73c46a3056 zdev/dracut: fix kdump by only activating required devices
This prevents out-of-memory (OOM) situations in the kdump crashkernel
environment.

Please note that the new dracut module 95zdev-kdump and the new library
zdev-lib.sh need to be packaged into the same (core) (sub)package as
95zdev.

This patch introduces a new dracut module "zdev-kdump", which is used
instead of module "zdev" when building a kdump initrd:

1. Ignore all persistently configured block devices and disable zfcp auto
LUN scanning => minimize the number of SCSI devices enabled during kdump.

2. Do not rely on chzdev's persistent configuration => work with systems
that do not use chzdev for persistent device configuration.

The detection of kdump is based on strict hostonly mode and on $IN_KDUMP.
See also
https://src.fedoraproject.org/rpms/kexec-tools commit
4eedcae5e154 ("dracut-module-setup.sh: don't include multipath-hostonly")
and https://github.com/dracutdevs/dracut commits
35e86ac117ac ("Merge 90-multipath-hostonly and 90-multipath")
a695250ec7db ("Introduce tri-state hostonly mode")
and
https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/mkdumprd#_17
https://src.fedoraproject.org/rpms/kexec-tools/blob/rawhide/f/dracut-module-setup.sh#_23.
The detection of kdump is also based on kdump_needed() in
https://github.com/openSUSE/kdump/blob/master/dracut/module-setup.sh.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-03-03 09:58:40 +01:00
Steffen Maier
f2c82bf2b5 zdev/dracut: fix hardcoded '/' as required mount or device
With the introduction of zdev for device configuration in v1.33.0,
it used a hardcoded "/" to refer to the root-fs.

Dracut has its own mechanism to find the root file system and to walk its
device dependencies.
Mkdumprd also has its own mechanism to interpret the kdump target
and invokes dracut so that dracut only considers arguments from mkdumprd
without any root-fs dracut would default to [--no-hostonly-default-device].

Use the dracut mechanism to walk device dependencies and individually
have chzdev treat each leaf-node in the dependency tree.
See also https://github.com/dracutdevs/dracut commit
83e0dc7a3dca ("Add for_each_host_dev_and_slaves for device only checking").
This enables the use of dracut options such as --add-device or
--mount used in turn by mkdumprd.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2023-03-03 09:58:20 +01:00
Vineeth Vijayan
1643af4578 zdev: dracut: modifiy the module-setup.sh
Export and import the configurations with zdev:early on the
site-specific configurations as well. Filter the site-specific
configurations by attribute "zdev:early" and import the output
to the corresponding sites.

Note that --site parameter does not work with the device type.

Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2022-11-03 17:38:53 +01:00
Peter Oberparleiter
3949c62f6f zdev: Add auto-config for PCI and crypto devices
PCI and crypto devices defined using the IBM Z Dynamic Partition Manager
(DPM) will start in an offline/unconfigured state that requires manual
intervention before the associated Linux function can be used. This
results for example in PCI networking interfaces being unavailable in a
distribution installer system.

Fix this by providing a udev rule and initial RAM-disk logic that
automatically enables PCI and crypto devices either during boot, or when
they are defined at run-time. This processing can be suppressed by
specifying the "rd.zdev=no-auto" parameter on the kernel command line.

Auto-configuration is limited to Linux running in DPM LPARs because
PCI-functions and crypto devices defined by DPM are always intended for
use by a single LPAR only.

For Linux running in classic-mode LPARs or virtual machines, leaving PCI
and crypto devices in an offline state may be useful to allow defining a
device as available to multiple systems, where only the system that
intends to make use of the device should enable it.

Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Reviewed-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2021-10-01 14:59:56 +02:00
Mark Post
a1697a581d zdev/dracut/95zdev/module-setup.sh: Add ctcm kernel module
The module-setup.sh script doesn't include the ctcm module
when building the initrd. This causes any CTC devices to
be bound by the LCS driver instead.

Closes: https://github.com/ibm-s390-tools/s390-tools/pull/79
Signed-off-by: Mark Post <mpost@suse.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2020-02-12 20:02:21 +01:00
Peter Oberparleiter
156450f359 zdev: Implement support for early device configuration
Enable user to specify that a device should be configured early, that is
during the initial RAM-disk boot phase. This may be necessary, e.g. to
override auto-configuration for a device which is also applied during
that boot phase. It may also be used to manually specify devices that
are required to access the root file system, such as networking devices.

Users can mark devices as requiring early configuration by specifying
a value of 1 for the newly added internal attribute zdev:early:

 # chzdev dasd-eckd 0.0.1234 -p zdev:early=1

This can be changed back by removing the attribute setting, or by
setting the attribute value to 0:

 # chzdev dasd-eckd 0.0.1234 -p -r zdev:early

or

 # chzdev dasd-eckd 0.0.1234 -p zdev:early=0

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2018-06-08 15:03:30 +02:00
Peter Oberparleiter
3fb356ebd2 zdev: Integrate firmware auto-configuration with dracut
Add a dracut hook that applies firmware-provided I/O configuration data
as auto-configuration during boot. This way, all I/O devices configured
by DPM are automatically brought online without further user
interaction.

This mechanism is active by default. It can be deactivated by specifying
the following parameter on the kernel command line:

  rd.zdev=no-auto

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
2018-06-08 15:03:30 +02:00
Peter Oberparleiter
0348a8443e zdev: Fix zdev dracut module aborting on unknown root device
Running dracut when the root device is not known to zdev (for example
because it is located on a virtio block device) will cause the zdev
dracut module to incorrectly return an error in the installkernel()
function. As a result dracut aborts with an error.

Fix this by ensuring that the non-zero exit code resulting from lszdev
not being able to determine the root device is not passed on to the
calling function. Also remove unnecessary error output in this case
by leaving the install() function early when the root device is not
known to zdev.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
2017-12-07 17:38:34 +01:00
Peter Oberparleiter
f3e552d67c zdev: Fix zdev dracut module temp file location
During processing, the zdev-provided dracut module creates a temporary
file using the mktemp tool. Due to a missing path specification
in the filename template, mktemp tries to create the temporary file
in the current working directory which fails if that directory is not
writable:

  # cd /sys
  # dracut -Nf
  mktemp: failed to create file via template 'dracut-zdev.XXXX': No such
  file or directory
  chzdev: Could not write to file : No such file or directory
  sed: can't read : No such file or directory
  chzdev: Could not open file : No such file or directory

Fix this by specifying option --tmpdir when calling mktemp.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
2017-08-31 17:41:15 +02:00
Michael Holzheu
b627b8d8e1 Initial s390-tools-2.0.0 import
This commit is based on the s390-tools-1.39.0 version.

Changes on top of s390-tools-1.39.0:

 - Add MIT license to all source files
 - Add LICENSE file
 - Transform REAMDE to README.md (markdown)
 - Add AUTHORS.md file
 - Add CONTRIBUTING.md file
 - Move changelog from README to CHANGELOG.md file

Reviewed-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
2017-08-21 10:55:40 +02:00