Re: [Xen-devel] [PATCH v2] VT-d PI: disable VT-d PI when APICv is disabled

2017-06-07 Thread Jan Beulich
>>> On 07.06.17 at 17:06, wrote: > On Wed, Jun 07, 2017 at 06:31:18AM -0600, Jan Beulich wrote: > On 07.06.17 at 11:29, wrote: >>> @@ -2266,8 +2267,10 @@ int __init intel_vtd_setup(void) >>> * We cannot use posted interrupt if X86_FEATURE_CX16 is >>> * not supported, since

Re: [Xen-devel] [PATCH v2] VT-d PI: disable VT-d PI when APICv is disabled

2017-06-07 Thread Chao Gao
On Wed, Jun 07, 2017 at 06:31:18AM -0600, Jan Beulich wrote: On 07.06.17 at 11:29, wrote: >> @@ -2266,8 +2267,10 @@ int __init intel_vtd_setup(void) >> * We cannot use posted interrupt if X86_FEATURE_CX16 is >> * not supported, since we count on this feature to >>

Re: [Xen-devel] [PATCH v2] VT-d PI: disable VT-d PI when APICv is disabled

2017-06-07 Thread Jan Beulich
>>> On 07.06.17 at 11:29, wrote: > @@ -2266,8 +2267,10 @@ int __init intel_vtd_setup(void) > * We cannot use posted interrupt if X86_FEATURE_CX16 is > * not supported, since we count on this feature to > * atomically update 16-byte IRTE in posted format. > + *

[Xen-devel] [PATCH v2] VT-d PI: disable VT-d PI when APICv is disabled

2017-06-07 Thread Chao Gao
From the context calling pi_desc_init(), we can conclude the current implementation of VT-d PI depends on CPU-side PI. If we disable APICv but enable VT-d PI explicitly in xen boot command line, we would get an assertion failure. This patch disables VT-d PI when APICv is disabled and adds some rel