[PATCH 4/4] KVM: hyper-v: Advertise support for fast XMM hypercalls

From: Siddharth Chandrasekaran <sidcha@amazon.de>
To: "K. Y. Srinivasan" <kys@microsoft.com>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	Stephen Hemminger <sthemmin@microsoft.com>,
	Wei Liu <wei.liu@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	<x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	"Sean Christopherson" <seanjc@google.com>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>,
	"Joerg Roedel" <joro@8bytes.org>
Cc: Siddharth Chandrasekaran <sidcha@amazon.de>,
	Alexander Graf <graf@amazon.com>,
	Evgeny Iakovlev <eyakovl@amazon.de>,
	<linux-hyperv@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<kvm@vger.kernel.org>
Subject: [PATCH 4/4] KVM: hyper-v: Advertise support for fast XMM hypercalls
Date: Wed, 7 Apr 2021 23:19:54 +0200	[thread overview]
Message-ID: <20210407211954.32755-5-sidcha@amazon.de> (raw)
In-Reply-To: <20210407211954.32755-1-sidcha@amazon.de>

Now that all extant hypercalls that can use XMM registers (based on
spec) for input/outputs are patched to support them, we can start
advertising this feature to guests.

Cc: Alexander Graf <graf@amazon.com>
Cc: Evgeny Iakovlev <eyakovl@amazon.de>
Signed-off-by: Siddharth Chandrasekaran <sidcha@amazon.de>
---
 arch/x86/include/asm/hyperv-tlfs.h | 4 ++--
 arch/x86/kvm/hyperv.c              | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/hyperv-tlfs.h b/arch/x86/include/asm/hyperv-tlfs.h
index e6cd3fee562b..1f160ef60509 100644
--- a/arch/x86/include/asm/hyperv-tlfs.h
+++ b/arch/x86/include/asm/hyperv-tlfs.h
@@ -49,10 +49,10 @@
 /* Support for physical CPU dynamic partitioning events is available*/
 #define HV_X64_CPU_DYNAMIC_PARTITIONING_AVAILABLE	BIT(3)
 /*
- * Support for passing hypercall input parameter block via XMM
+ * Support for passing hypercall input and output parameter block via XMM
  * registers is available
  */
-#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE		BIT(4)
+#define HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE		BIT(4) | BIT(15)
 /* Support for a virtual guest idle state is available */
 #define HV_X64_GUEST_IDLE_STATE_AVAILABLE		BIT(5)
 /* Frequency MSRs available */
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index bf2f86f263f1..dd462c1d641d 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -2254,6 +2254,7 @@ int kvm_get_hv_cpuid(struct kvm_vcpu *vcpu, struct kvm_cpuid2 *cpuid,
 			ent->ebx |= HV_POST_MESSAGES;
 			ent->ebx |= HV_SIGNAL_EVENTS;
 
+			ent->edx |= HV_X64_HYPERCALL_PARAMS_XMM_AVAILABLE;
 			ent->edx |= HV_FEATURE_FREQUENCY_MSRS_AVAILABLE;
 			ent->edx |= HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE;
 
-- 
2.17.1




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