From: Paolo Bonzini <pbonzini@redhat.com>
To: "Chen, Tiejun" <tiejun.chen@intel.com>,
Wanpeng Li <wanpeng.li@linux.intel.com>
Cc: Gleb Natapov <gleb@kernel.org>,
Alexei Starovoitov <alexei.starovoitov@gmail.com>,
Takashi Iwai <tiwai@suse.de>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] KVM: x86: fix access memslots w/o hold srcu read lock
Date: Fri, 31 Oct 2014 11:36:43 +0100 [thread overview]
Message-ID: <5453663B.90500@redhat.com> (raw)
In-Reply-To: <54531E7B.1040006@intel.com>
On 31/10/2014 06:30, Chen, Tiejun wrote:
>
> @@ -4442,6 +4442,7 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu)
> {
> struct vcpu_vmx *vmx = to_vmx(vcpu);
> struct msr_data apic_base_msr;
> + int idx;
>
> vmx->rmode.vm86_active = 0;
>
> @@ -4509,7 +4510,9 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu)
> vmcs_write32(TPR_THRESHOLD, 0);
> }
>
> + idx = srcu_read_lock(&vcpu->kvm->srcu);
> kvm_vcpu_reload_apic_access_page(vcpu);
> + srcu_read_unlock(&vcpu->kvm->srcu, idx);
>
> if (vmx_vm_has_apicv(vcpu->kvm))
> memset(&vmx->pi_desc, 0, sizeof(struct pi_desc));
Not enough; you can call vcpu_enter_guest -> kvm_apic_accept_events ->
kvm_vcpu_reset -> vmx_vcpu_reset while under the SRCU lock. The right
place to add the lock is kvm_arch_vcpu_setup.
Thanks,
Paolo
next prev parent reply other threads:[~2014-10-31 10:36 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-31 4:33 [PATCH] KVM: x86: fix access memslots w/o hold srcu read lock Wanpeng Li
2014-10-31 5:30 ` Chen, Tiejun
2014-10-31 6:11 ` Wanpeng Li
2014-10-31 10:36 ` Paolo Bonzini [this message]
2014-10-31 11:10 ` Wanpeng Li
2014-11-01 2:49 ` Wanpeng Li
2014-11-02 6:50 ` Paolo Bonzini
2014-11-02 7:10 ` Wanpeng Li
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