Hi Eric,
On Sat, Jul 02, 2005 at 09:22:20AM +0200, Eric Valette wrote:
> Greg KH wrote:
>
> > Why? Why not put it in ROM with your kernel image, look at how the
> > kernel build process does it with the "built-in" initramfs.
>
> Well, nowadays, most system have only flash because ROM does not enable
> to do firmware upgrade. Second, putting it in the kernel or as a
> separate flash section or in an initrd does not change the problem :
> something has to be stored on non volatile memory whereas you do not
> need that for devfs (except devfs code itself of course) but then you
> have udev instead of devfs...
Well, although I've never used udev because I've been using sort of an
equivalent called "preinit" for 4 years now, I don't totally agree with
you about the firmware upgrade : when you package your systems to allow
the customer to perform "firmware" upgrades, your image is already very
specific to a hardware model, and I don't see why you would need to
create /dev entries independantly from the kernel or rootfs. Speaking
for myself, my .preinit script which describes how to fill /dev entries
is on the rootfs and does not need to change once packaged.
However, I agree that I encountered difficulties using this system on
more generic hardware, because sometimes the raid devices did not exist,
or things like this caused trouble.
IMHO, a generic system should use a full /dev directory and an embedded
system should use just the strict minimum necessary for the specific
hardware to run.
> > I boot my boxes with nothing in /dev and have been for almost a year
> > now. udev works just fine for this, and so do some other programs that
> > work like udev does.
>
> Nothing in /dev but with initramfs. Same cost...
>
> BTW : valette@tri-yann->df /dev
> Filesystem 1K-blocks Used Available Use% Mounted on
> tmpfs 10240 2876 7364 29% /dev
>
>
> 2 MB RAM on my PC??? I must be missing something.
I think something went wrong, perhaps something like
# some_prog >/dev/null
while null did not exist. My /dev is a tmpfs too, but mounted with size=0,
so that I can only create inodes into it, but cannot write any data. One
other advantage of using size=0 is that "df" does not show it by default.
Cheers,
Willy
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
| |
 |