On Tue, Oct 18, 2011 at 01:37:32PM -0400, Avi Kivity wrote: > On 10/18/2011 06:35 PM, Roedel, Joerg wrote: > > On Tue, Oct 18, 2011 at 12:23:11PM -0400, Jan Kiszka wrote: > > > AMD processors apparently have a bug in the hardware task switching > > > support when NPT is enabled. If the task switch triggers a NPF, we can > > > get wrong EXITINTINFO along with that fault. On resume, spurious > > > exceptions may then be injected into the guest. > > > > > > We were able to reproduce this bug when our guest triggered #SS and the > > > handler were supposed to run over a separate task with not yet touched > > > stack pages. > > > > > > Work around the issue by continuing to emulate task switches even in > > > NPT mode. > > > > > > Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx> > > > > Acked-by: Joerg Roedel <joerg.roedel@xxxxxxx> > > > > Will there be an erratum published for this bug? Are all processors > affected? For now this behavior should be expected on all NPT capable processors. > I'd like to limit this to just the buggy processors, if and when fixed > processors become available. I don't know this yet, but I'll try to find out. Thanks, Joerg -- AMD Operating System Research Center Advanced Micro Devices GmbH Einsteinring 24 85609 Dornach General Managers: Alberto Bozzo, Andrew Bowd Registration: Dornach, Landkr. Muenchen; Registerger. Muenchen, HRB Nr. 43632 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
