On 13.05.2016 05:35, Paul Mackerras wrote: > On Thu, May 12, 2016 at 01:26:44PM +0200, Thomas Huth wrote: >> The SIAR and SDAR registers are available twice, one time as SPRs >> 780 / 781 (unprivileged, but read-only), and one time as the SPRs >> 796 / 797 (privileged, but read and write). The Linux kernel code >> currently uses the unprivileged SPRs - while this is OK for reading, >> writing to that register of course does not work. >> Since the KVM code tries to write to this register, too (see the mtspr >> in book3s_hv_rmhandlers.S), the contents of this register sometimes get >> lost for the guests, e.g. during migration of a VM. >> To fix this issue, simply switch to the privileged SPR numbers instead. >> >> Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx> > > Acked-by: Paul Mackerras <paulus@xxxxxxxxxx> *ping* Michael, could you please pick this patch up? I think it should rather go through the generic powerpc tree instead of kvm-ppc, since it also affects other parts than just KVM... Thanks, Thomas -- To unsubscribe from this list: send the line "unsubscribe kvm-ppc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html