Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH 07/17] KVM: monolithic: x86: adjust the section prefixes
To:     Andrea Arcangeli <aarcange@redhat.com>
Cc:     Vitaly Kuznetsov <vkuznets@redhat.com>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        Marcelo Tosatti <mtosatti@redhat.com>,
        Peter Xu <peterx@redhat.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20190920212509.2578-1-aarcange@redhat.com>
 <20190920212509.2578-8-aarcange@redhat.com>
 <2171e409-487f-6408-e037-3abc0b9aa312@redhat.com>
 <20190925121330.GA13637@redhat.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Openpgp: preference=signencrypt
Message-ID: <d621c8d7-ffc0-5d92-eacc-5af2d296b810@redhat.com>
Date:   Wed, 25 Sep 2019 14:32:05 +0200
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <20190925121330.GA13637@redhat.com>
Content-Type: text/plain; charset=utf-8
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On 25/09/19 14:13, Andrea Arcangeli wrote:
> 
> The __exit removed from unsetup is because kvm_arch_hardware_unsetup
> is called by kvm_init, so unless somehow kvm_init can go in the exit
> section and be dropped too during the final kernel link (which would
> prevent KVM to initialize in the first place at kernel boot), it's not
> feasible to call a function located in the exit section and dropped
> during the kernel link from there.
> 
> As far as I can tell with upstream KVM if you hit the
> kvm_arch_hardware_unsetup function during kvm_init error path it'll
> crash the kernel at boot because of it.
> 
> Removing __exit fixes that potential upstream crash and upstream bug.

You're right.

> The comment header was short, I'll add more commentary to the commit
> header to reduce the confusion about why removing __exit is needed.

Yes, thanks!

Paolo