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SubjectBug in console driver?

I suppose there is a bug in the 2.4-kernel console driver

It seems that (if there is a slow video device) this driver disables the
handling of interrupts while writing or switching the consoles.


If you use the VESA framebuffer, switching to another console prevents
updating the internal kernel clock (jiffies, xtime) for a short time.
This effect can grow up to some seconds:

Load the GNU Midnight Commander (mc) and synchronize kernel clock and
hardware clock with the command 'hwclock --hctosys'.

Then you can see the the difference with 'hwclock && date'.

# hwclock && date
Sun Sep 16 10:31:33 2001 -0,154753 ...
Sun Sep 10 10:31:32 CEST 2001

Now hold down the keys <Ctrl+o> for a some seconds. (This switches the
window of the Midnight Commander on/off many times)

If you now compare the clocks you yield a difference of some seconds:

# hwclock && date
Sun Sep 16 10:33:17 2001 -0,456384 ...
Sun Sep 16 10:33:12 CEST 2001

5 seconds - I think this is a bug.

My system:

Intel Pentium II, 512 MB RAM
NVIdia Riva TNT2 M64 with 32 MB
Kernel 2.4.4 and 2.4.7
SuSE Linux 7.2
VESA Framebuffer



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