Re: [PATCH RESEND 1/3] printk: convert byte-buffer to variable-lengthrecord buffer

From: Linus Torvalds
Date: Thu May 10 2012 - 16:53:01 EST


On Thu, May 10, 2012 at 1:46 PM, Joe Perches <joe@xxxxxxxxxxx> wrote:
>
> That's where I think you're still a bit
> uncertain how the _current_ printk system
> works.

No, you are. Read my answer from two days ago in this thread.

KERN_CONT is *not* the same as "". Not now, not ever. If you make it
the same, you're broken.

The reason is simple: KERN_CONT "<3>" should print out the string
"<3>". If you make KERN_CONT be "", it will do the wrong thing, and
think that the <3> is a priority marker.

Please people, this is subtle, and current code does things RIGHT. Any
code that changes it to do something else is almost certainly buggy.
The new semantics had better be the same as the old one.

The change to verify that 'current' matches the previous printout is
so far the *only* sane semantic change I've seen in this thread.
Everything else has been pure garbage.

Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/