On 07/09/2012 05:24 PM, Peter Zijlstra wrote: > On Mon, 2012-07-09 at 17:19 +0300, Gleb Natapov wrote: >> Yes, this is knows problem that I can't find time to fix. The crash is >> cause by CPU using host PEBS virtual address while guest is running >> which causes guest memory corruption. We should disable evens that use >> PEBS at the guest entry. > > Whoops.. so the hardware is reading the DS address as programmed by the > host (host linear address) and using it as a guest linear address? > > Quality stuff.. > > Disabling PEBS events for guests isn't pretty though..
We already have atomic MSR switching at guest entry/exit time. So it's not pretty in terms of not getting full profiling, but the code won't be too hard. Basically we just have to exclude_guest any pebs event. > but I guess the > only alternative is mapping the DS into the guest and reprogramming > MSR_IA32_DS_AREA which is all a little involved I suppose? Way too involved, especially as it's virtual addresses and we don't control the guest cr3. Note that the hardware won't fail gracefully. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
