From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
Subject: Re: [PATCH] eal/linux: fix multi-process cannot work
Date: Wed, 29 Mar 2017 16:19:15 +0100
Message-ID: <7c01afcd-20a7-f2a0-f230-04e5b04fb3c9@intel.com>
References: <1489681724-22114-1-git-send-email-jianfeng.tan@intel.com>
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Cc: benjamin.walker@intel.com, stable@dpdk.org
To: Jianfeng Tan <jianfeng.tan@intel.com>, dev@dpdk.org
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On 16/03/2017 16:28, Jianfeng Tan wrote:
> When binding with vfio-pci, secondary process cannot be started with
> an error message:
>
>      cannot find TAILQ entry for PCI device.
>
> It's due to: struct rte_pci_addr is padded with 1 byte for alignment
> by compiler. Then below comparison in commit 2f4adfad0a69
> ("vfio: add multiprocess support") will fail if the last byte is not
> initialized.
>
>      memcmp(&vfio_res->pci_addr, &dev->addr, sizeof(dev->addr)
>
> And commit cdc242f260e7 ("eal/linux: support running as unprivileged user")
> just triggers this bug by using a stack un-initialized variable.
>
> The fix is to use rte_eal_compare_pci_addr() for pci addr comparison.
>
> Fixes: 2f4adfad0a69 ("vfio: add multiprocess support")
> Fixes: cdc242f260e7 ("eal/linux: support running as unprivileged user")
> CC: stable@dpdk.org
>
> Reported-by: Rutkowski, Pawel <pawelx.rutkowski@intel.com>
> Signed-off-by: Jianfeng Tan <jianfeng.tan@intel.com>
> ---
>   lib/librte_eal/linuxapp/eal/eal_pci_vfio.c | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
> index 5f478c5..7d8b9fb 100644
> --- a/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
> +++ b/lib/librte_eal/linuxapp/eal/eal_pci_vfio.c
> @@ -355,7 +355,8 @@ pci_vfio_map_resource(struct rte_pci_device *dev)
>   	} else {
>   		/* if we're in a secondary process, just find our tailq entry */
>   		TAILQ_FOREACH(vfio_res, vfio_res_list, next) {
> -			if (memcmp(&vfio_res->pci_addr, &dev->addr, sizeof(dev->addr)))
> +			if (rte_eal_compare_pci_addr(&vfio_res->pci_addr,
> +						     &dev->addr))
>   				continue;
>   			break;
>   		}


Acked-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>