On Nov 4, 2008, at 8:00 PM, erik quanstrom wrote:
i don't think the kernel has this level of control.
let's suppose that we have a process that gets a stop message
that's doing i/o. let's suppose that it's doing io to a particularly
cranky device with lots of neat locks that really hates getting
interrupted. i don't know, something esoteric — say, ata. are you
really so sure that you can do what you want to this process
when ata io is going on?
Well, may be not. But I would like my right to shoot myself in the
foot not to be revoked ;-)
i sure would like to hear from someone who knows more about
what went into the design of notes. i don't think i've thought of
all the scary dark corners.
Same here.
Now, There are two issues on the table right now: the first
one has everything to do with notes, and I really would like to
better understand that area myself. Hence I'm all ears.
The other issue (how to manipulate the running process) has
less to do with notes per se. As I said, I do appreciate the reasoning
that a process has to be in a frozen state in order for writes
on /proc/n/mem to succeed. By a frozen state I still mean the
kind of a state that would prevent a scheduler to place it
on a runqueue. Stopped is one such state, but may be it
shouldn't be the only one.
Would it be completely unreasonable for devproc.c to also
allow writes for the processes which are in process of being
stopped?
Thanks,
Roman.
