[PATCH v2 1/8] KVM: SVM: Remove wbinvd in sev_vm_destroy()

[Sean Christopherson]

From: Zheyun Shen <szy0127 at sjtu.edu.cn>

Before sev_vm_destroy() is called, kvm_arch_guest_memory_reclaimed()
has been called for SEV and SEV-ES and kvm_arch_gmem_invalidate()
has been called for SEV-SNP. These functions have already handled
flushing the memory. Therefore, this wbinvd_on_all_cpus() can
simply be dropped.

Suggested-by: Sean Christopherson <seanjc at google.com>
Signed-off-by: Zheyun Shen <szy0127 at sjtu.edu.cn>
Reviewed-by: Tom Lendacky <thomas.lendacky at amd.com>
Signed-off-by: Sean Christopherson <seanjc at google.com>
---
 arch/x86/kvm/svm/sev.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 978a0088a3f1..e9fd3bcec37a 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -2883,12 +2883,6 @@ void sev_vm_destroy(struct kvm *kvm)
 		return;
 	}
 
-	/*
-	 * Ensure that all guest tagged cache entries are flushed before
-	 * releasing the pages back to the system for use. CLFLUSH will
-	 * not do this, so issue a WBINVD.
-	 */
-	wbinvd_on_all_cpus();
 
 	/*
 	 * if userspace was terminated before unregistering the memory regions
-- 
2.49.0.1112.g889b7c5bd8-goog