Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 26 May 2021 10:08:05 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     Haiyang Zhang <haiyangz@microsoft.com>
Cc:     bhelgaas@google.com, lorenzo.pieralisi@arm.com, wei.liu@kernel.org,
        linux-hyperv@vger.kernel.org, linux-pci@vger.kernel.org,
        kys@microsoft.com, olaf@aepfle.de, vkuznets@redhat.com,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] pci-hyperv: Add check for hyperv_initialized in
 init_hv_pci_drv()
Message-ID: <20210526100805.xpeen7td45cswqsw@liuwe-devbox-debian-v2>
References: <1621984653-1210-1-git-send-email-haiyangz@microsoft.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1621984653-1210-1-git-send-email-haiyangz@microsoft.com>
Precedence: bulk

On Tue, May 25, 2021 at 04:17:33PM -0700, Haiyang Zhang wrote:
> Add check for hv_is_hyperv_initialized() at the top of init_hv_pci_drv(),
> so if the pci-hyperv driver is force-loaded on non Hyper-V platforms, the
> init_hv_pci_drv() will exit immediately, without any side effects, like
> assignments to hvpci_block_ops, etc.
> 
> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> Reported-and-tested-by: Mohammad Alqayeem <mohammad.alqyeem@nutanix.com>

Reviewed-by: Wei Liu <wei.liu@kernel.org>

> ---
>  drivers/pci/controller/pci-hyperv.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
> index 6511648271b2..bebe3eeebc4e 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -3476,6 +3476,9 @@ static void __exit exit_hv_pci_drv(void)
>  
>  static int __init init_hv_pci_drv(void)
>  {
> +	if (!hv_is_hyperv_initialized())
> +		return -ENODEV;
> +
>  	/* Set the invalid domain number's bit, so it will not be used */
>  	set_bit(HVPCI_DOM_INVALID, hvpci_dom_map);
>  
> -- 
> 2.25.1
>