Installing Debian kernel headers package does not install all kernel headers
I am currently running the most recent update of Debian bookworm (which I think is built on Linux 6.1.0.32-amd64 or Linux-6.1.129-1, that's what uname -r returns). I have been trying to install a set...
View ArticleDifference between C-state and S-state?
I was going through the Linux power management files, and I am confused about the C and S states.The C-states are defined in /sys/devices/system/cpux/cpuidle/. From what I understand they are used to...
View ArticleLimit length of a scatterlist entry produced by dma_map_sg
The documentation for DMA in Linux kernel states:The implementation [of dma_map_sg] is free to merge several consecutive sglist entriesinto one (e.g. with an IOMMU, or if several pages just happen to...
View ArticleHow to configure buildroot to add a sound device?
I've used a given board configuration to reconfigure it for my individual board. My board has a CS4270 sound device of Cirrus Logic. My uImage is booting successfully on my target hardware, but an...
View ArticleKernel APIs to disable/enable CPU cores within a driver module
I have a linux kernel version 6.8.0-57-generic (Ubuntu Jammy). I want try disabling and enabling the cores in the CPU through the linux kernel module (from kernel space) What is the right way to do...
View ArticleRealtek RTL8822CE WiFi not working - Pop_OS 22.04
I'm having trouble getting WiFi working on Pop!_OS 22.04 with a Realtek RTL8822CE card. It worked fine until recently but now:WiFi randomly disconnectsSometimes the WiFi option disappears from...
View ArticleHow do I change the modules directory that the kernel searches
I am new to rebuilding the kernel and kernel modules and such, so I apologize if this is a poor question.I am running Centos 6.8 , 2.6.32.642.el6.x86_64. I am trying learn about device drivers and...
View Articlelsmod returns nothing on my embedded device
I have put a vendor supplied embedded Linux installation (called X-Linux) onto a hardware device. I ran lsmod to see what modules are loaded and nothing at all is shown. Also there is no /proc/modules...
View Articledriver install: module: x86/modules: Skipping invalid relocation target
My situation:I have a prebuilt kernel running fedora already installed and running. Now, I want to install the mcp251x and mcp25xfd driver modules, which depends on the can-dev driver module, so I need...
View ArticleAllocating contiguous physical memory using huge pages in kernel module
0I need a kernel module that allocates 8MB of physically contiguous memory using 2MB huge pages, in response to a user-space mmap() request. While I’ve successfully used alloc_pages() with 4KB pages to...
View Articlepwmconfig can't find fans, which are modifiable in uefi Bios
I would like to change the fan speeds on my PC. In the Asus BIOS settings, this is possible with PWM and DC (three of them are connected with 4 pins), but the running operating system seems to have...
View ArticleHow to debug the Linux kernel or device driver if the motherboard has no...
I am used to debug Linux device driver through the serial port on the motherboard to see the real-time message before the system hang.But now I have a brand-new server board, MSI MPG Z890 CARBON WIFI,...
View ArticleWhy does device registration not create a device file?
I'm currently learning about Linux device drivers and feel as if I have a fundamental misunderstanding on how devices are instantiated in Linux.Within a Linux module, I can call alloc_chrdev_region()...
View ArticleLoad new version of non-removable running kernel module
I have an embedded Linux device (Ubiquiti EdgeRouter-X, see this thread for more detail) for which I cross-compiled the kernel module nf_conntrack.ko (part of netfilter) to support a protocol that was...
View ArticleHow do I change the value of module.sig_enforce the Fedora kernel uses?
I am running a Fedora kernel ver: 4.15.3-300.fc27.i686). I am trying to load a custom device driver. When I try to use the device (via an open() call in a C program) the call errors out with errno...
View Articlehow do I find the current i2c bus speed?
I am building custom game controllers on Linux that use the i2c bus present in video ports such as HDMI, dvi, and VGA, on standard PC hardware (x86_64).I would like to verify my current i2c bus speed...
View Articledisabling I8042 driver completely
"i8042 is still probing even though I disabled CONFIG_SERIO_I8042. Does it have dependent configurations? Even after passing kernel command-line arguments: i8042.nopnp i8042.noaux, I still see an entry...
View ArticleConfigure kernel modules to load at boot
My distribution is Fedora 17 Gnome.Every time I reboot/restart my computer I need to run this command as root:modprobe rt2800usbHow can I make it permanent and enable this module at boot ?
View ArticleExplicit kernel module load at startup
I'm using grsecurity kernel which disallows automatic kernel load thus several systemd services don't work. After manually loading modules with modprobe and restarting module everything works correctly...
View ArticleAMDGPU module fails to load after Arch upgrade: "Cannot allocate memory"
I am running Arch Linux on a Lenovo laptop with an AMD Ryzen 5 CPU/integrated GPU. Previously, I was using the AMDGPU driver and the GPU was running very well with it. However, after running a full...
View ArticleQualcomm WIFI kernel drive ath12k_pci failing to load
My wifi disappeared and it isn't showing up on my PCCard0b:00.0 Network controller [0280]: Qualcomm Technologies, Inc WCN785x Wi-Fi 7(802.11be) 320MHz 2x2 [FastConnect 7800] [17cb:1107] (rev 01)...
View ArticlePCI passthrough: vfio-pci ignores ids of devices
I have 3 GPUs in my dual XEON server.I followed instructions on Arch wiki and set up vfio-pci with ids=10de:100c,10de:0e1a:$ modprobe -c | grep vfiooptions vfio_iommu_type1...
View Articleload driver with insmod get :disagrees about version of symbol module_layout
I compiled simple drive for Linux kernel for ARM system:$ uname -aLinux CR5 4.4.171-cr5 #2 Tue Mar 10 11:49:00 CET 2020 armv7l GNU/LinuxTo compile i used the config file from the up ruining system...
View ArticleFailed to register hook to tracepoint of signal_generate in Linux?
I am testing FTRACE in Linux VM (ubuntu 24.04) the kernel is Linux VirtualBox 6.11.0-26-generic.I wrote a kernel module to register a hook (probe) to kernel tracepoint of signal_generate, here is the...
View ArticleWhich rtl8821ae driver Linux Mint uses and how to apply it to any other distro?
I have a rtl8821ae-based 5GHz WiFi card on my desktop PC (It is pci-e TP-Link Archer T4E)I would like to install and use Linux to this desktop. I try different popular distros (Ubuntu, Fedora, Manjaro...
View ArticleTrace kernel object calls
We have strace to trace programs, ltrace for dynamic libraries, and others.Is there any equivalent for kernel objects, as in tracing just like strace but for a specific .ko?Thanks
View ArticleChange linux kernel release string
I hope to somehow change the release string, i.e. the string which uname -r prints, and more importantly for me, which is used to construct the path for module lookup, without actually compiling /...
View ArticleBuilding extra in-tree module that aren't configured by default?
I want to use the drivers/usb/host/xen-hcd.ko kernel module for USB support under Xen. This is controlled by the CONFIG_USB_XEN_HCD kernel configuration. I am using Debian, and it sets the...
View ArticleHow to make Realtek nic use r8168 driver
I've been trying (unsuccessfully) for the last few days to make my Realtek ethernet card to work. I have no problems with my wireless connection: only the ethernet connection doesn't work.I have Ubuntu...
View ArticleUSB mouse stopped working after plugging into a USB-C dock
So i bought an usb-c dock (jeswo), i plugged my usb mouse into that and it worked fine.I unplugged the dock, plugged into my steamdeck, played (worked fine) and then plugged back, my laptop did not...
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