[lkml]   [2003]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] don't create regular files in devfs (fwd)
On Tue, 14 Jan 2003, Christoph Hellwig wrote:

> On Tue, Jan 14, 2003 at 09:34:52AM +0000, Tigran Aivazian wrote:
> > Hi Christoph,
> >
> > I don't know about mtrr (probably does it for the same reason) but the
> > reason why microcode driver uses a regular file is because it needs
> > something that only regular files can provide --- the file size.
> >
> > This is an easy external "signifier" as to whether a successfull microcode
> > update has occurred or not.
> It seems to work without that feature on systems that don't have devfs..

Of course it works without it. I never said it is a required feature, only
a very nice to have. Namely:

a) if devfs is available it provides a regular file whose size can be
examined by applications and content read/written without much "fuss". In
particular it is very convenient to say "vi microcode" and examine the
content directly. If it was a device node then this would have been

b) if devfs is not available then a limited basic functionality is
provided --- i.e. just update the microcode on CPU(s) and write the log
messages in the kernel log.

Btw, having a size of mtrr is also useful for a similar reason.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:32    [W:0.037 / U:3.844 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site