[RFC PATCH V4 3/4] x86/hyperv: Don't use auto-eoi when Secure AVIC is available

[Tianyu Lan <ltykernel@gmail.com>]

From: Tianyu Lan <tiala@microsoft.com>

Hyper-V doesn't support auto-eoi with Secure AVIC.
So set the HV_DEPRECATING_AEOI_RECOMMENDED flag
to force writing the EOI register after handling
an interrupt.

Signed-off-by: Tianyu Lan <tiala@microsoft.com>
---
Change since RFC V3:
       - Update title prefix from "x86/Hyper-V" to "x86/hyperv"
---
 arch/x86/kernel/cpu/mshyperv.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index c78f860419d6..8f029650f16c 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -463,6 +463,8 @@ static void __init ms_hyperv_init_platform(void)
 		 ms_hyperv.max_vp_index, ms_hyperv.max_lp_index);
 
 	hv_identify_partition_type();
+	if (cc_platform_has(CC_ATTR_SNP_SECURE_AVIC))
+		ms_hyperv.hints |= HV_DEPRECATING_AEOI_RECOMMENDED;
 
 	if (ms_hyperv.hints & HV_X64_HYPERV_NESTED) {
 		hv_nested = true;
-- 
2.25.1