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SubjectRe: console_lock too early in printk???

Whoops, my mistake... :) I understand that copy_from_user should be called
effectively from outside of printk... but in my case, I was doign some
quick debugging work, adding lots of printk's and adding copy from user's
would have been "inconvenient". I appreciate that it's the right way to
do things. I'll through together a new patch that should be more
passable for everyone...

-Chris


On Sun, 2 Jul 2000, Chris Lattner wrote:

>
> Assuming I'm operating on which platform? What if the platform has
> copy_from_user defined as memcpy?
>
> -Chris
>
>
> On Sun, 2 Jul 2000, Russell King wrote:
>
> > Chris Lattner writes:
> > > Why are we grabbing the console lock so early? Is it really neccesary
> > > there (I don't think so)? With lots of printk's, concurrancy is
> > > needlessly killed (vsprintf can take a relatively long time...)
> >
> > Hint: do we care about the buffer that vsprintf is writing to? Do
> > we care that the messages could get corrupted? What's the point in
> > preventing two threads writing to the same memory space?
> >
> > Generally, calling printk with pointers to user-memory is not a good
> > thing to do - think about why we have copy_from_user/get_user/
> > strncopy_from_user and friends. IMHO, you're calling printk in an
> > illegal way, so it won't behave nicely to you.
> > _____
> > |_____| ------------------------------------------------- ---+---+-
> > | | Russell King rmk@arm.linux.org.uk --- ---
> > | | | | http://www.arm.linux.org.uk/~rmk/aboutme.html / / |
> > | +-+-+ --- -+-
> > / | THE developer of ARM Linux |+| /|\
> > / | | | --- |
> > +-+-+ ------------------------------------------------- /\\\ |
> >
>
>



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