The IIO subsystem exposes a 'label' sysfs file to help userspace better
identify its devices [1]. Standardized labels include the sensor type
along with its location, including 'accel-base' and 'accel-display'.
Most Chrome OS boards have two accelerometers that are indistinguishable
except for this label (or a 'location' sysfs file before Linux v6.0),
and need different mounting matrix corrections based on their location.
Add a udev rule that matches hwdb entries using this label, so we can
correct both accelerometers on these devices with hwdb entries. The
existing rules and hwdb entries are not modified to keep potential
out-of-tree entries working, but new entries in this form will override
existing ones. Also add currently standardized labels to parse-hwdb.py.
[1] https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-bus-iio
This can be useful for users of slow block devices.
For example, the persistent-storage rules are needed for USB floppy
drives be recognized by udisks2, but the extra blkid calls cause
thrashing for 25+ seconds after every disk change.
With this change, a user wishing to avoid the extra blkid invocation(s)
could create /etc/udev/rules.d/55-floppy-noprobe.rules as follows:
# Don't probe PC floppy drives
SUBSYSTEM=="block", KERNEL=="fd*", \
ENV{UDEV_DISABLE_PERSISTENT_STORAGE_BLKID_FLAG}="1"
# Don't probe USB floppy drives
SUBSYSTEM=="block", SUBSYSTEMS=="usb", \
ATTRS{bInterfaceClass}=="08", ATTRS{bInterfaceSubClass}=="04", \
ENV{UDEV_DISABLE_PERSISTENT_STORAGE_BLKID_FLAG}="1"
I didn't exclude floppies by default in this change, because floppy
devices are also emulated by some BIOSes/hypervisors in some cases, and
I don't know how many systems would fail to boot if /dev/disk/by-uuid/*
became unavailable for 'floppy disks' on those systems.
GIT_VERSION is not available as a config.h variable, because it's rendered
into version.h during builds. Let's rework jinja2 rendering to also
parse version.h. No functional change, the new variable is so far unused.
I guess this will make partial rebuilds a bit slower, but it's useful
to be able to use the full version string.
This adds another symlink for block devices:
/dev/disk/by-diskseq/<number>
where the number is the diskseq number as exposed by the kernel. It's
useful for apps because they can use it to open a device by diskseq, in
a way that is safe against device node reuse. I.e. if a device node path
like this is passed to an app it could open the device node via the
symlink and also parse the diskseq from the path. Once the device is
opened it could compare the parsed diskseq with the one returned by
BLKGETDISKSEQ on the open node, and if it matches they know they are
talking to the right device.
Fixes: #22906
Some SCSI tape devices use the same device ID (NAA registered device
designator) for the SCSI tape changer device and the first actual tape
device. For example, this one:
https://docs.oracle.com/en/storage/tape-storage/storagetek-sl150-modular-tape-library/slofs/bridged-tape-drives.html
You must connect the bridged drive to an HBA supporting multiple
LUNs (also referred to as LUN scanning). The SL150 Library uses a
single SCSI ID and two logical unit numbers (LUN). LUN 0 controls
the tape drive and LUN 1 which is configured as a SCSI medium
changer device controls the robotics. Data is sent to the remaining
LUN on the bridged drive or to LUNs on the other, unbridged drives
in the partition, all of which are configured as SCSI
sequential-access (tape) devices.
This may lead to errors because /dev/tape/by-id symlinks may sometimes
point to the st device representing the tape, and sometimes to the sg
device representing the changer.
Fix this by assigning an increased priority to the tape device, and creating
a separate -changer link for the SCSI tape changer.
Co-developed-by: Martin Wilck <mwilck@suse.com>
The approach to use '''…'''.split() instead of a list of strings was initially
used when converting from automake because it allowed identical blocks of lines
to be used for both, making the conversion easier.
But over the years we have been using normal lists more and more, especially
when there were just a few filenames listed. This converts the rest.
No functional change.
This reverts commit 94cb45d57f.
This rule set up a duplicate import:
$ udevadm test /devices/pci0000:00/0000:00:14.0/usb2/2-4/2-4.1/2-4.1.3
...
2-4.1.3: /usr/lib/udev/rules.d/40-libgphoto2.rules:9 Importing properties from results of builtin command 'usb_id'
2-4.1.3: /usr/lib/udev/rules.d/50-udev-default.rules:13 Skipping builtin 'usb_id' in IMPORT key
2-4.1.3: /usr/lib/udev/rules.d/50-udev-default.rules:13 Importing properties from results of builtin command 'hwdb --subsystem=usb'
2-4.1.3: hwdb modalias key: "usb:v17EFp3054:OneLink+ Giga"
2-4.1.3: /usr/lib/udev/rules.d/50-udev-default.rules:15 Importing properties from results of builtin command 'hwdb 'usb:v17efp3054''
2-4.1.3: No entry found from hwdb.
2-4.1.3: /usr/lib/udev/rules.d/50-udev-default.rules:15 Failed to run builtin 'hwdb 'usb:v17efp3054'': No data available
2-4.1.3: /usr/lib/udev/rules.d/50-udev-default.rules:52 MODE 0664
except that the existing one was done with uppercase digits and the full match pattern,
and the second one was done with lowercase digits.
With the previous commit we only have uppercase digits in our match patterns, so we can
drop the duplicate import. (Some other projects might have rules that used the lowercase
match patterns, and people might have some local rules that did that too. But the second
import was only added recently so I think it's better to rip off the bandaid quickly.)
Enable /dev/sgx_vepc access for the group 'sgx', which allows KVM-backed VMs
to host Intel Software Guard eXtension (SGX) enclaves. The upcoming QEMU
6.2 uses /dev/sgx_vepc to reserve portions of Enclave Page Cache (EPC) for
VMs. EPC is the reserved physical memory used for hosting enclaves.
When using "capture : true" in custom_target()s the mode of the source
file is not preserved when the generated file is not installed and so
needs to be tweaked manually. Switch from output capture to creating the
target file and copy the permissions from the input file.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
systemd-udevd.service listens to kernel uevents and is needed for device
units to be available.
systemd-udevd.service is misspelled as systemd-udev.service in a couple places.
Fixing typo.
The USB persist feature allows devices that can retain their state when
powered down to work across suspend/resume. This is in particular useful
for USB drives.
However, the persist feature can get in the way for devices that are
unable to retain their state when power is lost. An example of such
stateful devices are fingerprint readers where USB persist should be
disabled to ensure userspace can detect whether the USB device had a
power loss during system suspend.
This will initially be used by the libfprint autosuspend hwdb.
Closes: #20754
Import hwdb matches for USB devices (not interfaces) which don't usually
have a modalias so that it's possible to, for example, make them
available for unprivileged users.
ubifs volumes have a UUID and the built-in blkid is able to determine
it. The disk/by-uuid symlink isn't created because ubifs volumes are
not on block devices but on SUBSYSTEM="ubi" devices. See #20071.
Allow ubi subsystem devices to be processed by the persistent storage
rules too. The kernel device name matching already allows ubi* to pass.
The existing rules are sufficient to create the link.
The links look like other by-uuid symlinks, for example:
/dev/disk/by-uuid/9a136158-585b-4ba4-9b70-cbaf2cf78a1c -> ../../ubi0_1
