spapr: fix CAS-generated reset

The OV5_MMU_RADIX_300 requires special handling in the CAS negotiation
process. It is cleared from the option vector of the guest before
evaluating the changes and re-added later. But, when testing for a
possible CAS reset :

    spapr->cas_reboot = spapr_ovec_diff(ov5_updates,
                                        ov5_cas_old, spapr->ov5_cas);

the bit OV5_MMU_RADIX_300 will each time be seen as removed from the
previous OV5 set, hence generating a reset loop.

Fix this problem by also clearing the same bit in the ov5_cas_old set.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Cédric Le Goater 2017-09-08 16:33:43 +02:00 committed by David Gibson
parent 21f3f8db0e
commit 30bf9ed168

View File

@ -1581,6 +1581,13 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
* to worry about this for now.
*/
ov5_cas_old = spapr_ovec_clone(spapr->ov5_cas);
/* also clear the radix/hash bit from the current ov5_cas bits to
* be in sync with the newly ov5 bits. Else the radix bit will be
* seen as being removed and this will generate a reset loop
*/
spapr_ovec_clear(ov5_cas_old, OV5_MMU_RADIX_300);
/* full range of negotiated ov5 capabilities */
spapr_ovec_intersect(spapr->ov5_cas, spapr->ov5, ov5_guest);
spapr_ovec_cleanup(ov5_guest);