Linked by Thom Holwerda on Mon 21st Nov 2011 11:25 UTC, submitted by moondevil
OSNews, Generic OSes You all know MINIX - a microkernel operating system project led by Andrew Tanenbaum. The French Linux magazine LinuxFr.org has an interview with Andrew Tanenbaum about MINIX' current state and future. There's some interesting stuff in there.
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RE[5]: MicroKernel's
by Thom_Holwerda on Mon 21st Nov 2011 21:21 UTC in reply to "RE[4]: MicroKernel's"
Thom_Holwerda
Member since:
2005-06-29

To your 3rd point: I never saw a definition that says, all "modules" attached to a micro-kernel have to run in user mode.


This is a common misconception. People think the definition of a microkernel hinges on "everything must run in userland". This is not true. You can have a microkernel plus ALL of its modules running in kernelspace, and it'd still be a microkernel.

Reply Parent Score: 1

RE[6]: MicroKernel's
by DeepThought on Mon 21st Nov 2011 21:28 in reply to "RE[5]: MicroKernel's"
DeepThought Member since:
2010-07-17

Exactly my point :-)

Reply Parent Score: 1

RE[6]: MicroKernel's
by galvanash on Mon 21st Nov 2011 21:37 in reply to "RE[5]: MicroKernel's"
galvanash Member since:
2006-01-25

This is a common misconception. People think the definition of a microkernel hinges on "everything must run in userland".


Everything must be capable of running in userland... Not the same thing.

If you don't have code isolation and memory protection (when possible) you do not have a microkernel. If code in your file system can step directly on kernel memory then what is the point?

Reply Parent Score: 2

RE[7]: MicroKernel's
by Thom_Holwerda on Mon 21st Nov 2011 21:39 in reply to "RE[6]: MicroKernel's"
Thom_Holwerda Member since:
2005-06-29

"This is a common misconception. People think the definition of a microkernel hinges on "everything must run in userland".


Everything must be capable of running in userland... Not the same thing.
"

Exactly.

Reply Parent Score: 1

RE[7]: MicroKernel's
by DeepThought on Mon 21st Nov 2011 21:45 in reply to "RE[6]: MicroKernel's"
DeepThought Member since:
2010-07-17

You can have memory protection even if you run in supervisor mode. Only supervisor code is "capable" of changing the MMU/MPU to enhance its rights.
But if the supervisor code is proven (big word I know) to be correct (either mathematically or by design/review: Check IEC61508), then there is no problem.

But for sure, the more software is in userland the easier to protect the kernel and other parts of the system.

Reply Parent Score: 1