Re: [PATCH] Blacklist Dell Optiplex 320 from using the HPET

Guilherme M. Schroeder
2007-05-05T22:41:48Z

The lspci output:

00:00.0 Host bridge: ATI Technologies Inc Radeon Xpress 200 Host Bridge
(rev 01)
00:01.0 PCI bridge: ATI Technologies Inc RS480 PCI Bridge
00:12.0 SATA controller: ATI Technologies Inc SB600 Non-Raid-5 SATA
00:13.0 USB Controller: ATI Technologies Inc SB600 USB (OHCI0)
00:13.1 USB Controller: ATI Technologies Inc SB600 USB (OHCI1)
00:13.2 USB Controller: ATI Technologies Inc SB600 USB (OHCI2)
00:13.3 USB Controller: ATI Technologies Inc SB600 USB (OHCI3)
00:13.4 USB Controller: ATI Technologies Inc SB600 USB (OHCI4)
00:13.5 USB Controller: ATI Technologies Inc SB600 USB Controller (EHCI)
00:14.0 SMBus: ATI Technologies Inc SB600 SMBus (rev 13)
00:14.1 IDE interface: ATI Technologies Inc SB600 IDE
00:14.2 Audio device: ATI Technologies Inc SB600 Azalia
00:14.3 ISA bridge: ATI Technologies Inc SB600 PCI to LPC Bridge
00:14.4 PCI bridge: ATI Technologies Inc SB600 PCI to PCI Bridge
01:05.0 VGA compatible controller: ATI Technologies Inc RC410 [Radeon
Xpress 200]
02:09.0 Ethernet controller: Broadcom Corporation BCM4401-B0 100Base-TX
(rev 02)

And what about the patch? there's a final version to try?

Thanks.

john stultz wrote:
> On Sat, 2007-05-05 at 01:18 +0200, Andi Kleen wrote:
>> On Friday 04 May 2007 23:29:04 john stultz wrote:
>>> One of the 2.6.21 regressions was Guilherme's problem seeing his box
>>> lock up when the system detected an unstable TSC and dropped back to
>>> using the HPET.
>>>
>>> In digging deeper, we found the HPET is not actually incrementing on
>>> this system. And in fact, the reason why this issue just cropped up was
>>> because of Thomas's clocksource watchdog code was comparing the TSC to
>>> the HPET (which wasn't moving) and thought the TSC was broken.
>>>
>>> Anyway, Guliherme checked for a BIOS update and did not find one, so
>>> I've added a DMI blacklist against his system so the HPET is not used.
>>>
>>> Many thanks to Guilherme for the slow and laborious testing that finally
>>> narrowed down this issue.
>> Before going to hard to maintain DMI black lists we should first check
>> if it's a more general problem and can't it be solved better? Most likely
>> that system isn't the one with this issue and I don't want to apply
>> DMI patches forever.
>
> We can give it a whirl, I just didn't want to add yet another "compare
> with some other counter that may or may not work" check. In this case,
> probably reading three times in a row and getting the same result would
> be a clearly broken box.
>
>
>> In particular: what lspci chipset does it have? If it's Intel it might be
>> worth checking the datasheet if there is some "HPET stop" bit -- perhaps it
>> could be fixed up.
>
> Guilherme: Could you provide lspci output?
>
>
>> We seem to have a couple of Intel systems recently with HPET trouble.
>
> Ok, I wasn't aware it was a common issue.
>
> thanks
> -john
>
>
>