Fix, IO-APIC + timer doesn't work with hardy under VMware.

Alok Kataria akataria at
Sat Aug 22 01:00:51 UTC 2009

Hi Stefan,

While testing Ubuntu 8.04.3 under VMware. We have seen situations when
we hit this panic in the guest, during bootup. 
" Kernel panic - not syncing: IO-APIC + timer doesn't work! Try using
the 'noapic' kernel parameter" 

I had fixed this problem for mainline some time back but I guess I
forgot to ask you guys to pick this patch.
The direct port of the mainline commit
(3da757daf86e498872855f0b5e101f763ba79499) gave a couple of trivial
merge conflicts for hardy. The backport (lpj_tsc.patch) of the patch
which applies to hardy-git is attached. 

Many user's might hit this when they start running 8.04.3 guests, so it
would be great if you could apply the fix at your earliest. Please note
that, with VMware hypervisor specific changes which went in the 8.04.3
kernel (tsc improvements) the likelihood of anybody hitting this on AMD
systems is slightly increased.
Other Newer Ubuntu releases already have the fix from mainline.

While I am at it, I also noticed that for 64bit AMD systems the cpu
frequency can differ from tsc frequency, and their are no print messages
which tell the user about the TSC frequency on such systems. So I wrote
up a simple patch which prints this value for x86-64
(print_hypervisor_tsc_freq.patch). Please consider this too for hardy.

Let me know if you have question about either patch. 


P.S. : I tried to file a BUG for this issue, but I must say that I
haven't found the launchpad-bugzilla to be too helpful. My attempt to
file a bug failed with some timeout error (Error ID: OOPS-1330D61). 

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