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Can user access hardware directly?
It is definitely possible to access hardware from user space. Especially if the hardware registers are memory mapped.
Why is the OS the only software that can access hardware?
Because an operating system must hide the computer’s hardware, and manage the hardware resources, it needs to prevent the application software from accessing the hardware directly. Without this sort of protection, the operating system would not be able to do its job.
What is user space authentication?
This method of authentication allows a user to authenticate to an authentication process configured specifically for the user. The process is configured as a value of the User Authentication Configuration attribute in the user’s profile.
What is the relationship between hardware and operating system?
Functions of computer hardware includes input, processing, storage and output. Functions of OS includes manage computer resources, establish user interface, execute and provide services for application software. Its main purpose is to make any electronic or computer device work and execute tasks.
How are device drivers used in user space?
In the context of device drivers, this can provide user-space applications direct access to the device memory, which includes register configuration and I/O descriptors. All accesses by the application to the assigned address range ends up directly accessing the device memory.
Can a user space program access the kernel?
Whilst a user-space program is not allowed to access kernel memory, it is possible for the kernel to access user memory. However, the kernel must never execute user-space memory and it must also never access user-space memory without explicit expectation to do so.
Do you need a user space driver for Linux?
It’s possible to use it as root to disable interrupts, and one particular program used to used to use it–the clock program. However, this kills SMP machines. If you need to use cli (), you need a kernel-space driver, and a user-space driver will only cause grief as more and more Linux users use SMP machines.
How to block Ethernet interrupts in user space?
This can be addressed by the use of a blocking read () call on the UIO device entry, which would allow the user-space application to block on receive interrupts from the Ethernet device.