Questions tagged [sysfs]
Sysfs is a Linux filesystem, normally mounted on /sys, which provides information about hardware and kernel components.
167 questions
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Disconnected block device remains in /sys, is not seen as detected when re-connect
System is Linux Mint 21 based. My USBstick was receiving some files and after message "Do not disconnect" had disappeared I unplugged it. This time though waiting whirl remained in Disks GUI ...
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Distinguish between configs and logs/debugs/statistics within sysfs (/sys)
sysfs is a feature of the Linux kernel that allows kernel code to export information to user processes via an in-memory filesystem. The organization of the filesystem directory hierarchy is strict, ...
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How to re-enable a USB port after disabling it in sysfs?
I have disabled a USB (2.0) port on a production Linux system with this command: echo 1 > /sys/bus/usb/devices/usb2/2-1/2-1.8/port/disable It successfully disabled the 8th USB port on hub #1. ...
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sysfs missing CPU thermal_throttle information
Background Information: I'm running Ubuntu 24.04.1 LTS (Noble Numbat, kernel 6.8.0-51-generic) on an AMD Ryzen 9 7950X3D, and I'm investigating some odd behavior where the CPU governor/driver will ...
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Udev rule for syfs class/device attribute ownership
This was originally asked on Stack Overflow, but it was closed for being off-topic. Hopefully this is the right forum for the question. I'm writing a character device driver that exposes class and ...
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ERROR in file_io_posix.cc, trying to locate scaling_cur_freq and scaling_max_freq and couldn't find it
I'm trying to execute a container based on Ubuntu 20.04 and some additional dependencies. It ended up in an error where the project (something external) is looking for files/programs, as shown below. ...
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How to run samples/rpmsg_client_sample in Linux?
I am learning RPMSG in Linux, and I found there is a samples/rpmsg_client_sample.c. I built it into a kernel module, but I don't know how to make its probe function to be called? And is there any ...
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Where to create symlinks to sysfs iio files
I wrote a driver that exposes I2C registers via an IIO device, this device operates in direct mode (read/write directly to files in sysfs), the files are correctly created in sysfs and work fine. I ...
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Replicating 'udisks power-off' behavior (without udisks)
udisks exists for regular users, root must (and is) able to live without it, I need help figuring out how. The goal is to do exactly what udisks power-off /dev/sdX does without udisks. hdparm is out ...
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where to enable /sys/fs/cgroup/memory/0/memory.usage_in_bytes?
I try to count total memory usage in linux via /sys/fs For this I've found /sys/fs/cgroup/memory/0/memory.usage_in_bytes in https://docs.kernel.org/admin-guide/cgroup-v1/memory.html#user-interface i'...
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structure /sys/fs/cgroup/memory.stat
What is the structure of linux memory via /sys/fs/cgroup/memory.stat? what is the anon memory? What is the file memory? how to get the full used memory via /sys/fs?
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Does udev have an issue with the 'hwmon' subsystem?
I have a temp/humidity sensor connected to the i2c-0 interface on a Raspberry Pi: Rpi OS ver 'bookworm'. It works fine, and I can read sensor values from the files in /sys/class/hwmon/hwmon2 (or ...
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Why is this folder duplicated in `sysfs`?
I have a Raspberry Pi that is running the 'bookworm' version of the OS; the 64-bit version of the OS if that makes any difference. I've installed one of the SHT3X temperature & humidity sensors, ...
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Watching for /sys/class/net file changes using systemd
I'm trying to get a systemd service to restart when some ethernet cable gets plugged in, by monitoring changes to the /sys/class/net/eth0/carrier_up_count system file. I tried creating a systemd path ...
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Are numbers in sysfs presented in decimal or hex?
I am looking at files in sysfs, specifically in /sys/bus/usb/devices The files contains small numbers, expressed as two characters, for example "00" All of the examples that I have contain ...
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