On 3/27/2021 8:18 AM, Kuppuswamy Sathyanarayanan wrote:
In non-root TDX guest mode, MWAIT, MONITOR and WBINVD instructions
are not supported. So handle #VE due to these instructions as no ops.
Signed-off-by: Kuppuswamy Sathyanarayanan
<sathyanarayanan.kuppusw...@linux.intel.com>
Reviewed-by: Andi Kleen <a...@linux.intel.com>
---
Changes since previous series:
* Suppressed MWAIT feature as per Andi's comment.
* Added warning debug log for MWAIT #VE exception.
arch/x86/kernel/tdx.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/arch/x86/kernel/tdx.c b/arch/x86/kernel/tdx.c
index e936b2f88bf6..fb7d22b846fc 100644
--- a/arch/x86/kernel/tdx.c
+++ b/arch/x86/kernel/tdx.c
@@ -308,6 +308,9 @@ void __init tdx_early_init(void)
setup_force_cpu_cap(X86_FEATURE_TDX_GUEST);
+ /* MWAIT is not supported in TDX platform, so suppress it */
+ setup_clear_cpu_cap(X86_FEATURE_MWAIT);
In fact, MWAIT bit returned by CPUID instruction is zero for TD guest.
This is enforced by SEAM module.
Do we still need to safeguard it by setup_clear_cpu_cap() here?
+
tdg_get_info();
pv_ops.irq.safe_halt = tdg_safe_halt;
