Re: [patch] printk from userspace

Linus Torvalds
2002-08-14T04:20:45Z

On Wed, 14 Aug 2002, Alexander Viro wrote:
>
>
> On Wed, 14 Aug 2002, Benjamin LaHaise wrote:
>
> > On Tue, Aug 13, 2002 at 09:11:55PM -0700, Andrew Morton wrote:
> > > It requires root.
> >
> > Still, unlike kernel code that can be rate limited, this call cannot.
> > Besides, isn't adding yet another syscall that's equivalent to write(2)
> > a reason to take this patch and burn it along with the vomit its caused?
>
> I have a better suggestion. How about we make write(2) on /dev/console to
> act as printk()? IOW, how about making _all_ writes to console show up in
> dmesg?
>
> Then we don't need anything special to do logging _and_ we get output
> of init scripts captured. For free. dmesg(8) would pick that up, klogd(8)
> will work as is, etc.
>
> Linus?

Well, apart from the fact that you get into an endless loop with klogd,
who wants to spew the kernel messages back to the console under some
circumstances..

That said, I like the notion. I've always hated the fact that all the
boot-time messages get lost, simply because syslogd hadn't started, and
as a result things like fsck ran without any sign afterwards. The kernel
log approach saves it all in one place.

But /dev/console just sounds potentially _too_ noisy.

Linus