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* [9fans] Question on #r/nvram
@ 2003-05-14 20:48 ron minnich
  2003-05-14 20:52 ` Russ Cox
  0 siblings, 1 reply; 5+ messages in thread
From: ron minnich @ 2003-05-14 20:48 UTC (permalink / raw)
  To: 9fans


Is there any reason to have #r/nvram readable and writeable only be eve?
Is this historical? I have commented out the permission check for eve but
I'm wondering if that is the wrong thing to do.

You can't really do this with the eve permission check:
bind '#r' rtc
echo blah > rtc/nvram

which makes it tough to reset nvram.

thanks

ron



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [9fans] Question on #r/nvram
  2003-05-14 20:48 [9fans] Question on #r/nvram ron minnich
@ 2003-05-14 20:52 ` Russ Cox
  2003-05-14 21:04   ` ron minnich
  0 siblings, 1 reply; 5+ messages in thread
From: Russ Cox @ 2003-05-14 20:52 UTC (permalink / raw)
  To: 9fans

> which makes it tough to reset nvram.

Only if you're not eve.  If you're not eve,
what right do you have to reset the nvram?



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [9fans] Question on #r/nvram
  2003-05-14 20:52 ` Russ Cox
@ 2003-05-14 21:04   ` ron minnich
  2003-05-14 21:11     ` Russ Cox
  0 siblings, 1 reply; 5+ messages in thread
From: ron minnich @ 2003-05-14 21:04 UTC (permalink / raw)
  To: 9fans

On Wed, 14 May 2003, Russ Cox wrote:

> Only if you're not eve.  If you're not eve,
> what right do you have to reset the nvram?

Yes, that is true. It makes all kinds of sense until you have a bad key in
CMOS. What's the approved way to nuke the bad key in CMOS besides yanking
the battery?

In other words, I can do this as bootes
echo blah > /dev/sdC0/nvram
but can not do this:
echo blah > /dev/rtc/nvram

and that would be useful.

ron



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [9fans] Question on #r/nvram
  2003-05-14 21:04   ` ron minnich
@ 2003-05-14 21:11     ` Russ Cox
  2003-05-14 22:02       ` ron minnich
  0 siblings, 1 reply; 5+ messages in thread
From: Russ Cox @ 2003-05-14 21:11 UTC (permalink / raw)
  To: 9fans

Eve is the host owner.  If you are not the host owner,
then you should not be able to write to nvram.
If you are the host owner, then you can.

I just tried on my terminal:
	g% echo hi >'#r/nvram'
	g%

No problems.  (Of course, I'll probably regret
that when I reboot.)

If the machine is running with bootes as the
host owner, then bootes should be able to

	echo blah >'#r/nvram'

or even

	echo blah >/dev/nvram

assuming '#r' is bound onto /dev.



^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [9fans] Question on #r/nvram
  2003-05-14 21:11     ` Russ Cox
@ 2003-05-14 22:02       ` ron minnich
  0 siblings, 0 replies; 5+ messages in thread
From: ron minnich @ 2003-05-14 22:02 UTC (permalink / raw)
  To: 9fans

On Wed, 14 May 2003, Russ Cox wrote:

> Eve is the host owner.  If you are not the host owner,
> then you should not be able to write to nvram.
> If you are the host owner, then you can.

hokay, I'll try it again.

thanks

ron



^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2003-05-14 22:02 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2003-05-14 20:48 [9fans] Question on #r/nvram ron minnich
2003-05-14 20:52 ` Russ Cox
2003-05-14 21:04   ` ron minnich
2003-05-14 21:11     ` Russ Cox
2003-05-14 22:02       ` ron minnich

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