distinguish between user mode and kernel mode?
Answer Posted / rhino
Kernel Mode (System Mode) :
in this mode executing code has complete and unrestricted
access to the underlying hardware. It can execute any CPU
instruction and reference any memory address.
Kernel mode is generally reserved for the lowest-level,
most trusted functions of the operating system. Crashes in
kernel
mode are catastrophic; they will halt the entire PC.
When the CPU is in kernel mode, it is assumed to be
executing trusted software, and thus it can execute any
instructions
and reference any memory addresses (i.e., locations in
memory).
The kernel (which is the core of the operating system and
has complete control over everything that occurs in the
system)
is trusted software, but all other programs are considered
untrusted software.
Thus, all user mode software must request use of the kernel
by means of a system call in order to perform privileged
instructions, such as process creation or input/output
operations.
User Mode :
In User mode, the executing code has no ability to directly
access hardware or reference memory. Code running in user
mode must delegate to system APIs to access hardware or
memory.
Due to the protection afforded by this sort of isolation,
crashes in user mode are always recoverable. Most of the
code
running on your computer will execute in user mode.
| Is This Answer Correct ? | 21 Yes | 2 No |
Post New Answer View All Answers
Enlist some filename manipulation commands in unix.
Is there any method to erase all files in the current directory, along with its all sub-directories, by using only one command?
What are awk commands?
What does awk stand for?
What is the use of tee command?
How do I delete files from command prompt?
What is the command to view process running?
How do I run a bash script?
How do I search for a file in unix command?
Explain command to display different lines that are found when compare two files?
What is s and g in sed command?
What are the unix commands?
What is the use of find command in unix?
What is the difference between grep and grep?
What is the use of sed command in unix?