something about the process stack!

[jincuteguy]

You know when a process executes a TRAP or is interrupted, the operating system uses a separate stack to execute any operating system code rather than the stack of the current process. Anyone know why the operating systems designers select this type of implementation?

 

[goloap]

Based on what I know, there are two main reasons to do this:

1) It is safer, the OS stack is protected such that other process can't corrupt it. Which is easily done with bad programming.

2) The OS has access directly to kernel functions, which are not available to other process. It can't thus put them on the stack or else there would be some access violation.

In ancient times they had no statistics so they had to fall back on lies

 

[mito]

Can an ordinary process halt the system? If it accesses the hardware so much and directly, there's a risk.

/\/\ito