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0

When you run it as root, losetup -f will automatically create loop devices as needed if there aren't any free ones available. So rather than doing it yourself with mknod, the easiest way to create a new loop device is with sudo losetup -f. That approach will give you a free existing loop device if one exists, or automatically create a new one if needed.


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It seems that you haven't loaded the kernel module "vboxdrv". Use 'modprobe' to load the module and then try. In case if something goes wrong try installing again the required packages. There is a pretty good documentation on arch linux.


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As far as I know, the initramfs cpio archive is just linked into the kernel. Hence, this should work: use dd to extract the range between c17fd8cc and c19d7b90 unpack the resulting data ny using an CPIO unpacker.


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/var/log/dmesg stores the content of the 'kernel ring buffer', a memory buffer created by the kernel at boot in which to store log data it generates as soon as you get past the bootloader phase. A ring buffer is a special kind of buffer that is always a constant size, removing the oldest messages when new messages come in. The text stored in the kernel ...


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Yes, all of this has to do with logging. No, none of it has to do with runlevel or "protection ring". The kernel keeps its logs in a ring buffer. The main reason for this is so that the logs from the system startup get saved until the syslog daemon gets a chance to start up and collect them. Otherwise there would be no record of any logs prior to the ...


1

jkt123's will work for most distributions I guess. However for Arch Linux it didn't work, at least not with the packages I have available. The indices you can set with grub-set-default only correspond to the main menu entries. The kernel options are however in a submenu. So either you move the kernel entry out of the submenu into the main menu or you put ...


2

Kernel mode and user mode are a hardware feature, specifically a feature of the processor. Processors designed for mid-to-high-end systems (PC, feature phone, smartphone, all but the simplest network appliances, …) include this feature. Kernel mode can go by different names: supervisor mode, privileged mode, etc. On x86 (the processor type in PCs), it is ...


1

As mentioned in the comments, you can set the default kernel to boot into using the grub-set-default X command, where X is the number of the kernel you want to boot into. In some distributions you can also set this number by editing the /etc/default/grub file and setting GRUB_DEFAULT=X, and then running update-grub. The number is the index to an array of ...


0

There is a very nice discussion here http://rudd-o.com/en/linux-and-free-software/tales-from-responsivenessland-why-linux-feels-slow-and-how-to-fix-that which boils down to decreasing swappiness, with the idea that to increase perceived responsiveness of the system one should prevent swapping out the code (and this is what happens). This is not really an ...


3

"Linux" proper is only the kernel. When we talk about "Linux" as an operating system, it is a conflation of the kernel and all of the other software that is distributed with it in a Linux distribution. The switch between user and kernel mode happens when you make a system call, which is any of the functions documented in manual section 2. That is, if you ...


0

Check if your CentOS has Automatic Bug Reporting Tool (ABRT) installed and running. See https://fedorahosted.org/abrt/wiki/AbrtDeployment2 for more info. In short if abrtd deamon is running then it is what handles creation of core dump files. In this case, you need to configure abrtd deamon via /etc/abrt/abrt.conf. You may use "BlackList" directive to ...


3

Debian (and Ubuntu and other derivatives) divides Linux kernel packages into several parts: linux-image-VERSION-PATCHLEVEL-FLAVOR contains the kernel image that is loaded by the bootloader, a file containing the symbol table (used by some system tools), a file containing the kernel configuration (informative for the system administrator), and modules that ...


0

netinet is currently not a kernel module, so i suggest to add your modified file to sys/conf/files instead.


2

For compiling kernel module you should create Makefile and to include kernel module makefile /usr/src/share/mk/bsd.kmod.mk for example: # Note: It is important to make sure you include the <bsd.kmod.mk> makefile after declaring the KMOD and SRCS variables. # Declare Name of kernel module KMOD = module # Enumerate Source files for kernel module ...


1

Linux Mint comes in two flavors. Ubuntu based Debian based (LMDE) The Ubuntu based version (the default one) is guaranteed to work with Ubuntu packages and the LMDE is guaranteed to be compatible with packages from the Debian repository. Even though most debs of Debian works in Ubuntu it still some non-compatible packages due to File system hierarchy ...


2

I expect library symbols will be different, even if you've got what appear to be the same versions in-place. As a half-measure, look for statically-built binaries; then you only have to worry about getting a myriad file locations all correct so the app stops complaining. In many, many cases, if not all, it's simpler to rebuild the app for the environment ...


11

It might help to up /proc/sys/vm/page-cluster (default: 3). From the kernel documentation (sysctl/vm.txt): page-cluster page-cluster controls the number of pages up to which consecutive pages are read in from swap in a single attempt. This is the swap counterpart to page cache readahead. The mentioned consecutivity is not in terms of ...


5

You may try adding the programs you most care about to a cgroup and tuning swappiness so that the next time the application runs the programs you add are less likely to be candidates for swapping. Some of their pages will likely still be swapped out but it may get around your performance problems. A large part of it is probably just the "stop and start" ...


4

It seems to me that you can't magically "make the system responsive again". You either incur the penalty or reading pages back from swap space into memory now or you incur it later, but one way or the other you incur it. Indeed, if you do something like swapoff -a && swapon -a then you may feel more pain rather than less, because you force some pages ...


1

In the modern kernel, devices are described via the device tree. The device tree will contain a description of various hardware elements and names of their respective drivers. When a device matches a device tree entry, the device driver associated with it is alerted. The device driver then probes the device to test capabilities. mac80211 is a framework ...


0

I think the following links can help you: Interrupts and Interrupt Handling Interrupt Handling Difference between an IRQ and interrupt vector in linux kernel Where does an interrupt vector table get stored in Linux?


1

There's a fantastic pair of articles on LWN that describe how syscalls work on Linux: "Anatomy of a system call", part 1 and part 2.


1

All firmware which isn't distributable under the GPL-2 isn't provided within the kernel, but is available separately in the linux-firmware project. You'll find OLAND_pfp.bin there; you can clone the repository and run make install as root, which will install all the firmware in appropriate sub-directories of /lib/firmware.


0

After kernel compilation, one must execute the command depmod -a to refresh the module order in directory /lib/modules/<kernel_version>


1

On FreeBSD there is a difference between reboot and shutdown -r now. From the reboot man page: Normally, the shutdown(8) utility is used when the system needs to be halted or restarted, giving users advance warning of their impending doom and cleanly terminating specific programs.


0

It is technically possible if one of the device supports USB OTG, in which a port may act as master or as slave. You may set up the OTG device as slave, and let it act as an USB hard disk drive (so you don't even need special driver on the master). This is what a lot of phones and some cameras do. If you connect them to a printer they become master; if ...


15

Yes this is possible, but it is not possible by cutting two USB cables with USB-A connectors (what is normally going into the USB on your motherboard) and cross connecting the data cables. If you connect the USB power lines on such a self made cable, you are likely to end up frying your on-board USB handling chip. Don't try this at home! On most computer ...


3

you could use a USB bridge device which is available in a cable form-factor like this ... http://www.usbgear.com/link/ (auto-play video warning)


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Mounting or remounting a filesystem is done using the mount(2) syscall. When remounting, this takes the target location (the mountpoint), the flags to be used in the mount operation, and any extra data used for the specific filesystem involved. When remounting read-only, the flags used are MS_RDONLY and MS_REMOUNT; you're also supposed to provide any other ...


0

I take it that you changed into linux-3.19.3 directory before running the make commands. And it seems that this version of the kernel that was running before you compiled and installed. Try to boot into an older kernel using grub (the same kernel with rescue will probably not work). Using a vanilla source on an Ubuntu system has never worked for me. It ...


0

The manual page gives 3 reasons. Note that ftime(3), profil(3), and ulimit(3) are implemented as library functions. Some system calls, like alloc_hugepages(2), free_hugepages(2), ioperm(2), iopl(2), and vm86(2) exist only on certain architectures. Some system calls, like ipc(2), create_module(2), init_module(2), and delete_module(2) ...


2

Most of them used to be implemented at some point in Linux kernel history time, but some like at least vserver are still implemented in specific kernels. The majority of these calls is now essentially obsolete but their slot remains and contains a stub which role is not to break old code and allow a re-implementation in a specialized or new kernel should it ...


0

If you can go with full kernel source tree, here are the steps I have followed in order to compile and install a driver on the source tree: Lets say you have the kernel sources extracted at /sources/linux-3.19 cd /sources/linux-3.19 make mrproper make menuconfig Here make sure to select your driver with "m" label. For instance, if you select to build ...


1

To be sure that your machine generates a "core" file when a core is generated then you should confirm "systcl" settings of your machine. IMO, following should be the settings (minimal) in /etc/sysctl.conf kernel.core_pattern = /var/crash/core.%t.%p kernel.panic=10 kernel.unknown_nmi_panic=1 Do not forget to execute "sysclt -p" after making changes in ...


0

When you are installing your kernel the responsible script is copying kernel image and initramfs into your /boot directory. If a previous kernel image with the same name already exist, it is renamed by appending .old to its name. CONFIG_LOCALVERSION: Append an extra string to the end of your kernel version. This will show up when you type uname, ...


1

Virtualbox allows to configure two types of SCSI controllers, one being LSILOGIC the other Buslogic compatible. Those should be supported by the bt(4) and mpt(4) drivers. You can remove all other SCSI controllers If you use IDE/SATA controllers you can remove all SCSI drivers.


0

You need kernel-devel package for this kernel: 2.6.32-042stab102.9 Try install vzkernel-devel. Also you can ask your VZ provider support about source of kernel they use.


0

somewhere on the internet i found suggestion the issue is related to fused FS . so i reformatted the partition from NTFS to EXT4 then all the issues were gone and no more kernel panic


0

If you can access the U-Boot command line console, you can enter printenv to see U-Boot's environment variables. Some of these variables define the commands that are run at boot time - beginning with bootcmd. Based on the output you've provided, it appears U-Boot is trying different load commands for different filesystems - for example, ext2load vs ...


1

It's in kernel space. This article from Linux Device Drivers is a bit dated but still should generally apply: https://lwn.net/images/pdf/LDD3/ch18.pdf However, there is some effort recently towards replacing the kernel driver with a userspace console called "KMSCON" -- see that project's site for more: http://cgit.freedesktop.org/~dvdhrm/kmscon/tree/README



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