Received-SPF: pass (google.com: domain of linux-kernel+bounces-44104-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:40f1:3f00::1 as permitted sender) client-ip=2604:1380:40f1:3f00::1;
Message-ID: <3ef50211-7746-4054-84b6-6861d6a91341@linux.intel.com>
Date: Tue, 30 Jan 2024 16:14:15 +0800
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v18 050/121] KVM: x86/tdp_mmu: Sprinkle __must_check
To: isaku.yamahata@intel.com
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
 isaku.yamahata@gmail.com, Paolo Bonzini <pbonzini@redhat.com>,
 erdemaktas@google.com, Sean Christopherson <seanjc@google.com>,
 Sagi Shahar <sagis@google.com>, Kai Huang <kai.huang@intel.com>,
 chen.bo@intel.com, hang.yuan@intel.com, tina.zhang@intel.com
References: <cover.1705965634.git.isaku.yamahata@intel.com>
 <8f7d5a1b241bf5351eaab828d1a1efe5c17699ca.1705965635.git.isaku.yamahata@intel.com>
From: Binbin Wu <binbin.wu@linux.intel.com>
In-Reply-To: <8f7d5a1b241bf5351eaab828d1a1efe5c17699ca.1705965635.git.isaku.yamahata@intel.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit


On 1/23/2024 7:53 AM, isaku.yamahata@intel.com wrote:
> From: Isaku Yamahata <isaku.yamahata@intel.com>
>
> TDP MMU allows tdp_mmu_set_spte_atomic() and tdp_mmu_zap_spte_atomic() to
> return -EBUSY or -EAGAIN error.  The caller must check the return value and
> retry.  Sprinkle __must_check to guarantee it.

Reviewed-by: Binbin Wu <binbin.wu@linux.intel.com>

>
> Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
> ---
>   arch/x86/kvm/mmu/tdp_mmu.c | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
> index fdc6e2221c33..2aacfab25e93 100644
> --- a/arch/x86/kvm/mmu/tdp_mmu.c
> +++ b/arch/x86/kvm/mmu/tdp_mmu.c
> @@ -507,9 +507,9 @@ static void handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
>    *            no side-effects other than setting iter->old_spte to the last
>    *            known value of the spte.
>    */
> -static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
> -					  struct tdp_iter *iter,
> -					  u64 new_spte)
> +static inline int __must_check tdp_mmu_set_spte_atomic(struct kvm *kvm,
> +						       struct tdp_iter *iter,
> +						       u64 new_spte)
>   {
>   	u64 *sptep = rcu_dereference(iter->sptep);
>   
> @@ -539,8 +539,8 @@ static inline int tdp_mmu_set_spte_atomic(struct kvm *kvm,
>   	return 0;
>   }
>   
> -static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
> -					  struct tdp_iter *iter)
> +static inline int __must_check tdp_mmu_zap_spte_atomic(struct kvm *kvm,
> +						       struct tdp_iter *iter)
>   {
>   	int ret;
>