Re: CML2-2.1.3 is available

Peter Samuelson
2002-01-16T06:30:34Z

[esr]
> The version I just released does exactly that. Well, not exactly; it
> actually looks at fstab -- /proc/mounts gives you '/dev/root' rather
> than a physical device name in the root entry.

/etc/fstab is hardly guaranteed to be accurate either. The kernel
mounts the root device based on its command line and any pivot_root()
calls you make, not based on /etc/fstab.

[In practice, I imagine most people don't lie to fstab. The fsck init
script would get annoyed.]

But the horse's mouth, in this case, is /proc/sys/kernel/real-root-dev,
a 16-bit decimal int which represents a device number in
MAJOR*256+MINOR format. There *may* also the 'root=' asciiz string in
/proc/cmdline, which will be a 4-digit hex number, but that is not
reliable - because of pivot_root() among other things.

On my system, real-root-dev gives 8453, which means /dev/hde5, which is
on ide2. According to /proc/ide/ide2/config, it is a PCI device of
type 105a:4d30 [Promise Ultra100], so you can derive
CONFIG_BLK_DEV_PDC202XX as well as CONFIG_BLK_DEV_IDEDISK.

Peter