So what stops the scehduler from putting interrupt context to sleep and taking next schedulable process and passing it the control? The problem is that the interrupt context is not a process, and therefore cannot be put to sleep. When an interrupt occurs, the processor saves the registers onto the stack and jumps to the … Read more
The really simplified answer is that the kernel runs in kernel space, and normal programs run in user space. User space is basically a form of sand-boxing — it restricts user programs so they can’t mess with memory (and other resources) owned by other programs or by the OS kernel. This limits (but usually doesn’t … Read more
Docker never uses a different kernel: the kernel is always your host kernel. If your host kernel is “compatible enough” with the software in the container you want to run it will work; otherwise, it won’t. “Containers” Are Just Process Configuration The key thing to understand is that a Docker container is not a virtual … Read more
We seem to have ported Das U-Boot successfully. There’s evidence that that is a faulty assumption. Just before calling the kernel, the pointer theKernel is 10008000 and not 10800000. Which version of U-Boot are you using? In both 2012.10 and 2013.04 versions of U-Boot, the variable theKernel is only declared and used by code for … Read more
First and foremost, assuming that you are talking about x86-64, we can see that the virtual memory map for x86-64 is: ======================================================================================================================== Start addr | Offset | End addr | Size | VM area description ======================================================================================================================== | | | | 0000000000000000 | 0 | 00007fffffffffff | 128 TB | user-space virtual memory, different per mm … Read more
Docker uses the host operating system kernel, there is no custom or additional kernel inside the container. All containers running on the machine are sharing this “host” kernel. See for more information this question on SuperUser.
Since you have an ACPI-enabled platform the best approach is to provide the ASL excerpts for given devices. Because of Intel Galileo platform for IoT the Atmel 24 series EEPROM has got its own ACPI ID and an excerpt will be simple: DefinitionBlock (“at24.aml”, “SSDT”, 5, “”, “AT24”, 1) { External (_SB_.PCI0.I2C2, DeviceObj) Scope (\_SB.PCI0.I2C2) … Read more
tl;dr – We switch modes to supervisor and use that stack. You are missing the key point of where control is handed to the CPU via the vector table and the mode is switched. See: entry-armv.S and __vectors_start. The vector stubs is the code where control is initially sent after the branch in the main … Read more
What is the difference between them? Image: the generic Linux kernel binary image file. zImage: a compressed version of the Linux kernel image that is self-extracting. uImage: an image file that has a U-Boot wrapper (installed by the mkimage utility) that includes the OS type and loader information. A very common practice (e.g. the typical … Read more