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Message-ID: <fdd2d7e2-cf7c-4bfd-39d2-af5a3cf60b26@maciej.szmigiero.name>
Date:   Thu, 5 May 2022 15:37:26 +0200
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Subject: Re: [PATCH] x86: Function missing integer return value
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To:     Juergen Gross <jgross@suse.com>, Li kunyu <kunyu@nfschina.com>
Cc:     x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
        pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com,
        jmattson@google.com, joro@8bytes.org, tglx@linutronix.de,
        mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        hpa@zytor.com, seanjc@google.com
References: <20220505113218.93520-1-kunyu@nfschina.com>
 <ba469ccc-f5c4-248a-4c26-1cbf487fd62e@suse.com>
From:   "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
In-Reply-To: <ba469ccc-f5c4-248a-4c26-1cbf487fd62e@suse.com>
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On 5.05.2022 13:36, Juergen Gross wrote:
> On 05.05.22 13:32, Li kunyu wrote:
>> This function may need to return a value
>>
>> Signed-off-by: Li kunyu <kunyu@nfschina.com>
>> ---
>>   arch/x86/kvm/mmu/mmu.c | 2 ++
>>   1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
>> index 64a2a7e2be90..68f33b932f94 100644
>> --- a/arch/x86/kvm/mmu/mmu.c
>> +++ b/arch/x86/kvm/mmu/mmu.c
>> @@ -6500,6 +6500,8 @@ static int kvm_nx_lpage_recovery_worker(struct kvm *kvm, uintptr_t data)
>>           kvm_recover_nx_lpages(kvm);
>>       }
>> +
>> +    return 0;
> 
> This statement is not reachable, so the patch is adding unneeded dead
> code only.

Maybe some static checker isn't smart enough to figure this out.

In this case it would probably be better to also change:
> if (kthread_should_stop())
>     return 0;

into:
> if (kthread_should_stop())
>     break;

so the newly introduced code isn't dead.

> Juergen

Thanks,
Maciej