KVM: PPC: Book3S: Enable XIVE native capability only if OPAL has required functions

There are some POWER9 machines where the OPAL firmware does not support
the OPAL_XIVE_GET_QUEUE_STATE and OPAL_XIVE_SET_QUEUE_STATE calls.
The impact of this is that a guest using XIVE natively will not be able
to be migrated successfully.  On the source side, the get_attr operation
on the KVM native device for the KVM_DEV_XIVE_GRP_EQ_CONFIG attribute
will fail; on the destination side, the set_attr operation for the same
attribute will fail.

This adds tests for the existence of the OPAL get/set queue state
functions, and if they are not supported, the XIVE-native KVM device
is not created and the KVM_CAP_PPC_IRQ_XIVE capability returns false.
Userspace can then either provide a software emulation of XIVE, or
else tell the guest that it does not have a XIVE controller available
to it.

Cc: stable@vger.kernel.org # v5.2+
Fixes: 3fab2d1058 ("KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode")
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Paul Mackerras
2019-08-26 16:21:21 +10:00
parent d22deab696
commit 2ad7a27dea
6 changed files with 21 additions and 4 deletions
+7
View File
@@ -800,6 +800,13 @@ int xive_native_set_queue_state(u32 vp_id, u32 prio, u32 qtoggle, u32 qindex)
}
EXPORT_SYMBOL_GPL(xive_native_set_queue_state);
bool xive_native_has_queue_state_support(void)
{
return opal_check_token(OPAL_XIVE_GET_QUEUE_STATE) &&
opal_check_token(OPAL_XIVE_SET_QUEUE_STATE);
}
EXPORT_SYMBOL_GPL(xive_native_has_queue_state_support);
int xive_native_get_vp_state(u32 vp_id, u64 *out_state)
{
__be64 state;