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From:   Hao Peng <flyingpenghao@gmail.com>
Date:   Sat, 8 Oct 2022 00:00:41 +0800
Message-ID: <CAPm50a+aygp3T1mNjzGXtL2nyNm-mHFZ3YO8F7eO0gCxZDuQsA@mail.gmail.com>
Subject: [PATCH] kvm: x86: keep srcu writer side operation mutually exclusive
To:     pbonzini@redhat.com
Cc:     kvm@vger.kernel.org, linux-kernel@vger.kernel.org
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From: Peng Hao <flyingpeng@tencent.com>

Synchronization operations on the writer side of SRCU should be
invoked within the mutex.

Signed-off-by: Peng Hao <flyingpeng@tencent.com>
---
 arch/x86/kvm/pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 8a7dbe2c469a..619151849980 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -602,9 +602,9 @@ int kvm_vm_ioctl_set_pmu_event_filter(struct kvm
*kvm, void __user *argp)

        mutex_lock(&kvm->lock);
        filter = rcu_replace_pointer(kvm->arch.pmu_event_filter, filter, 1);
+       synchronize_srcu_expedited(&kvm->srcu);
        mutex_unlock(&kvm->lock);

-       synchronize_srcu_expedited(&kvm->srcu);
        r = 0;
 cleanup:
        kfree(filter);
--
2.27.0