From 597cb7968cb6243e915ba9599195656be14773e5 Mon Sep 17 00:00:00 2001
From: Wanpeng Li <wanpengli@tencent.com>
Date: Tue, 4 Jan 2022 22:41:03 -0800
Subject: [PATCH] KVM: SEV: Mark nested locking of kvm->lock

Both source and dest vms' kvm->locks are held in sev_lock_two_vms.
Mark one with a different subtype to avoid false positives from lockdep.

Fixes: c9d61dcb0bc26 (KVM: SEV: accept signals in sev_lock_two_vms)
Reported-by: Yiru Xu <xyru1999@gmail.com>
Tested-by: Jinrong Liang <cloudliang@tencent.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1641364863-26331-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/svm/sev.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 7656a2c5662a6..be28831412209 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -1565,7 +1565,7 @@ static int sev_lock_two_vms(struct kvm *dst_kvm, struct kvm *src_kvm)
 	r = -EINTR;
 	if (mutex_lock_killable(&dst_kvm->lock))
 		goto release_src;
-	if (mutex_lock_killable(&src_kvm->lock))
+	if (mutex_lock_killable_nested(&src_kvm->lock, SINGLE_DEPTH_NESTING))
 		goto unlock_dst;
 	return 0;
 
-- 
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