Re: VIA 686 timer bugfix incomplete

[Jonas Diemer <diemer@gmx.de>]

On Wed, 7 Nov 2001 20:25:46 +0100
Vojtech Pavlik <vojtech@suse.cz> wrote:

...
> The bug #2 can trigger the test for #1, because the timer is read just
> after the timer interrupt happens and thus the value is usually around
> 11920, which, plus 256 is larger than 11920.
> 

so why don't you simply add a new option to the config file, that says "work
around Via 686a bug"? that way, only ppl who have the bug need the fix.

...
> Only timer.c and apic.c do proper locking.
> 

well, but as I said, the workaround in arch/i386/kernel/time.c is incomplete, at
least in linus' kernel tree!

> The problem is how to work around the bugs 1) and 2) reliably and
> without too much performance impact. I haven't found a feasible way to
> do that yet.

well, just use the option described above. that way, ppl that need the fix can
choose to use it (at a cost of performance), others simply don't need checking.

-jonas

PS: CC me in your answers plz, I am not subscribed to the list.