on 11/02/2010 06:37 Alan Cox said the following: > Here is what I know. Several of us, myself included, have been able to > reproduce either lockups or machine check exceptions when BOTH the machine > check driver and superpages are enabled on AMD family 10h processors. There > have been no reports of this problem on either Intel or earlier AMD > processors. Moreover, there is no evidence of instability in AMD family 10h > processors until the machine check driver is enabled. By default, FreeBSD > 8.0 enables superpages but disables the machine check driver. So, running > natively, i.e., without virtualization, you shouldn't experience a problem, > unless you explicitly enable the machine check driver. However, running on > top of a hypervisor, like vSphere 4, you might face a problem because the > hypervisor might enable machine check exceptions, regardless of what the > FreeBSD guest does. I really don't know whether vSphere 4 enables machine > check exception or not. If it does, then either you disable the use of > superpages in the FreeBSD guest, or you find a way to disable the machine > check driver in the hypervisor.
I'd like to mention another possibility, just in case: machine check might be enabled/done by firmware (e.g. BIOS). This typically could be the case for high-end-ish/server systems. -- Andriy Gapon _______________________________________________ [email protected] mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "[email protected]"
