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17

The distro kernels are all compiled from the official source, with distro specific patches applied. These patches are relatively minor compared to the scope of the kernel itself. As long as you know what you are doing, you can substitute a custom kernel into any of the mainstream distros, although this is discouraged since it may cause a mismatch with ...


15

SCSI and ATA are entirely different standards. They are currently both developed under the aegis of the INCITS standards organization but by different groups. SCSI is under technical committee T10, while ATA is under T13.1 ATA was designed with hard disk drives in mind, only. SCSI is a broader standard, capable of controlling mass storage devices, tape ...


14

First of all, nobody "gets the kernel from Linus". Yes, Linus is still actively involved in the kernel's development and has final say in any disputes but he most certainly does not write it alone! The wikipedia page on the Linux kernel is quite good on the subject: The kernel changes made in year 2007 have been submitted by no less than 1900 developers ...


3

Linux uses RAM in a different way from what other operating systems do. Rather than sitting there with unused RAM, Linux stores data that it thinks might be used in RAM-any applications may be cached here, files, etc. As a result, Linux RAM usage is higher than what is used by running applications. This extra usage is buffered to be sued by other things. ...


3

No. The kernel is specifically designed to disallow user mode code from running in ring 0. In order to do this, you will have to write a kernel module, and then talk to your module through some method (perhaps ioctl) from your user mode program. Writing a kernel module does not require patching the kernel, but the kernel module must be written very ...


3

As the kernel documentation states, /dev/nfs is not a real device but only a hint to the kernel to use NFS as rootfs. You'll also have to tell the kernel where to find this root through the nfsroot parameter or a properly set up DHCP daemon. For the latter one to work you'll also have to either configure your kernel to auto-configure its network ...


3

Varnish appears to use a plain memory-mapped file for its shared memory (instead of, e.g., POSIX shm_open). From the source: loghead = mmap(NULL, heritage.vsl_size, PROT_READ|PROT_WRITE, MAP_HASSEMAPHORE | MAP_NOSYNC | MAP_SHARED, heritage.vsl_fd, 0); On BSD, MAP_NOSYNC requests that the kernel not write the shared data to disk unless forced ...


3

A FILE structure in C is typically called the file handle and is a bit of abstraction around a file descriptor: The data type FILE is a structure that contains information about a file or specified data stream. It includes such information as a file descriptor, current position, status flags, and more. It is most often used as a pointer to a ...


2

You might see some information from here. Generally, a file descriptor is an index for an entry in a kernel-resident data structure containing the details of all open files. In POSIX, this data structure is called a file descriptor table, and each process has its own file descriptor table. The user application passes the abstract key to the kernel through a ...


2

go into the BIOS of the host and rearrange the order of the hard drives and removable drives. This will adjust the order as it appears to the Linux kernel.


2

Try this from the Ask Ubuntu section: http://askubuntu.com/questions/318583/how-can-i-solve-fixed-channel-1-mon0-is-on-channel-1-issue-when-using-airo The lastest dev version has the --ignore-negative-one option. Obtain the lastest dev version from subversion: Install Subversion: On Debian/Ubuntu: sudo apt-get install subversion Then, obtain it via svn. ...


2

I want to add these file into my kernel such way that when kernel start this hello.o file execute and run What you are trying to achieve shouldn't be made through kernel edition. Executing a program at boot time can be handled in much simpler ways, without need for kernel programming experience. You can: Execute it when your shell starts: Write ...


2

1) Isn't the next kernel's release maintaining everything than was included in previous release ? If you mean everything then the answer will always be: "not everything" because there were changes. 2) If not what's the purpose of naming a kernel with higher number if it's not having a content of previous one (like in apps) There is often a ...


1

Despite what file says, it turns out to be debugging symbols after all. A thread about this on the LKML led me to try: make INSTALL_MOD_STRIP=1 modules_install And low and behold, a comparison from within the /lib/modules/x.x.x directory; before: > ls -hs kernel/crypto/anubis.ko 112K kernel/crypto/anubis.ko And after: > ls -hs ...


1

kernel.org has some excellent documentation on Applying Patches to the Linux Kernel. Essentially, you use the patch command. Once you have acquired the patch (here called patchfile), place it in your build directory and then issue the command: patch -p <num> < patchfile where <num> is the number of leading slashes to remove from the ...


1

the new ATA driver in the kernel use /dev/sda, the old drivers are still supported but you will have to edit your kernel by chrooting into you system using a livecd. Device drivers ---> <*> ATA/ATAPI/MFM/TLL support (deprecated) <*> Serial ATA and Parallel ATA drivers ---> For chrooting I always use the gentoo minimal installation cd ...


1

The documentation for the pam_loginuid PAM module gives a pretty good hint: The pam_loginuid module sets the loginuid process attribute for the process that was authenticated. This is necessary for applications to be correctly audited. This PAM module should only be used for entry point applications like: login, sshd, gdm, vsftpd, crond and atd. ...


1

Compression algorithms are declared in lib/decompress.c. Gzip is defined in lib/decompress_inflate.c and doesn't get any special status; it'll only be there if CONFIG_DECOMPRESS_GZIP is y when the kernel is compiled. The list of available compression algorithms is the compressed_formats structure. Since it's defined as static, it isn't available in other ...


1

Ok, so here's the way the boot process works: firmware > bootloader maybe > kernel ${parameters} > initramfs > userspace maybe On a redhat installation disk their dracut system of scripts is what builds and constitutes initramfs and their anaconda installation system constitutes the final userspace. It is udev that handles the device setup - as in, it ...


1

Or should I simply ignore it? Unused variables could be an indication of a coding mistake. If you are satisfied this is not the case and want to suppress the warning for a particular variable, you can use a (GCC specific) __attribute__ tag, e.g.: /* Unused parameter (in definition, not declaration): */ void somefunc (int x __attribute__ ((unused))) { ...


1

"Variable set but not used" warnings are informational. According to the official documentation, -Wunused-but-set-variable controls the behavior of: Warn[ing] whenever a local variable is assigned to, but otherwise unused (aside from its declaration). This warning is enabled by -Wall. The purpose is to catch situations where the programmer assigns a ...



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