Normal users do not have permissions to access /proc/1/root, so
'systemd-detect-virt -r' fails, but the output, even at debug level
is cryptic:
$ SYSTEMD_LOG_LEVEL=debug build/systemd-detect-virt -r
Failed to check for chroot() environment: Permission denied
Let's make this a bit easier to figure out:
$ SYSTEMD_LOG_LEVEL=debug build/systemd-detect-virt -r
Cannot stat /proc/1/root: Permission denied
Failed to check for chroot() environment: Permission denied
I looked over other users of files_same(), and I think in general the message
at debug level is OK for them too.
Meta's resource control demo project[0] includes a benchmark tool that can
be used to calculate the best iocost solutions for a given SSD.
[0]: https://github.com/facebookexperimental/resctl-demo
A project[1] has now been started to create a publicly available database
of results that can be used to apply them automatically.
[1]: https://github.com/iocost-benchmark/iocost-benchmarks
This change adds a new tool that gets triggered by a udev rule for any
block device and queries the hwdb for known solutions. The format for
the hwdb file that is currently generated by the github action looks like
this:
# This file was auto-generated on Tue, 23 Aug 2022 13:03:57 +0000.
# From the following commit:
# ca82acfe93
#
# Match key format:
# block:<devpath>:name:<model name>:
# 12 points, MOF=[1.346,1.346], aMOF=[1.249,1.249]
block:*:name:HFS256GD9TNG-62A0A:fwver:*:
IOCOST_SOLUTIONS=isolation isolated-bandwidth bandwidth naive
IOCOST_MODEL_ISOLATION=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119
IOCOST_QOS_ISOLATION=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00
IOCOST_MODEL_ISOLATED_BANDWIDTH=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119
IOCOST_QOS_ISOLATED_BANDWIDTH=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00
IOCOST_MODEL_BANDWIDTH=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119
IOCOST_QOS_BANDWIDTH=rpct=0.00 rlat=8807 wpct=0.00 wlat=59023 min=100.00 max=100.00
IOCOST_MODEL_NAIVE=rbps=1091439492 rseqiops=52286 rrandiops=63784 wbps=192329466 wseqiops=12309 wrandiops=16119
IOCOST_QOS_NAIVE=rpct=99.00 rlat=8807 wpct=99.00 wlat=59023 min=75.00 max=100.00
The IOCOST_SOLUTIONS key lists the solutions available for that device
in the preferred order for higher isolation, which is a reasonable
default for most client systems. This can be overriden to choose better
defaults for custom use cases, like the various data center workloads.
The tool can also be used to query the known solutions for a specific
device or to apply a non-default solution (say, isolation or bandwidth).
Co-authored-by: Santosh Mahto <santosh.mahto@collabora.com>
getty-generator enables serial-getty@.service for virtualizer consoles
that it can find in /sys/class/tty. To make sure this works for
virtio consoles, let's make sure we load the module is loaded early
so that the /sys/class/tty/hvc0 exists before we run getty-generator.
This is the function version of STARTSWITH_SET(). We also move
STARTSWITH_SET() to string-util.h as it fits more there than in
strv.h and reimplement it using startswith_strv().
Let's avoid confusing developers and users when log messages suddenly
stop getting logged to kmsg because of ratelimiting by logging an
additional message if we start ratelimiting log messages to kmsg.
When trying to mount a partition that is encrypted without the
encryption first having been set up we want to return a
recognizable error (EUNATCH). This was broken by
80ce8580f5 which added an allowlist check
for permissible file systems first. Let's reverse the check order, so
that we get EUNATCH again, as before. (And leave EIDRM as error for the
failed allowlist check).
An overflow here (i.e. the counter reaching 2^32 within a ratelimit time
window) is not so unlikely. Let's handle this somewhat sanely
and simply stop counting, while remaining in the "limit is hit" state until
the time window has passed.
I made the mistake to look into what is installed into
/usr/lib/systemd/system-shutdown/ on Fedora. fwdupd among other things
assumes /var/ is available from these callouts, though it is not in the
general case.
Hence, let's emphasize this in the documentation a bit more.
See added code comment for a longer explanation. TLDR: Linux maintains
distinct block device caches for partition and "whole" block devices,
and a simply BLKFLSBUF should make the worst confusions this causes go
away.
DHCP static leases are looked up by the client identifier as send by
the client, while configured based on MAC. As RFC 2131 states the client
identifier is an opaque key and must not be interpreted by the server
this means that DHCP clients can (/will) also use a client identifier
which is not a MAC address. One of these clients actually is
systemd-networkd which uses an RFC 4361 by default to generate the
client identifier. For these kind of DHCP clients static leases thus
don't work because of this mismatch between configuring a MAC address
but the server matching based on client identifier. This adds a fallback
to try to look up a configured static lease based on the "chaddr" of the
DHCP message as this will always contain the MAC address of the client.
Fixes#21368
If the device unit is not the head of the list saved in
Manager.devices_by_sysfs, then it is not necessary to replace the
existing hashmap entry. This should not change any behavior, just
refactoring.
