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Date:   Mon, 03 Aug 2020 15:59:49 -0700 (PDT)
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To:     baijiaju@tsinghua.edu.cn
Cc:     doshir@vmware.com, pv-drivers@vmware.com, kuba@kernel.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: vmxnet3: avoid accessing the data mapped to
 streaming DMA
From:   David Miller <davem@davemloft.net>
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From: Jia-Ju Bai <baijiaju@tsinghua.edu.cn>
Date: Sun,  2 Aug 2020 21:11:07 +0800

> In vmxnet3_probe_device(), "adapter" is mapped to streaming DMA:
>   adapter->adapter_pa = dma_map_single(..., adapter, ...);
> 
> Then "adapter" is accessed at many places in this function.
> 
> Theses accesses may cause data inconsistency between CPU cache and 
> hardware.
> 
> To fix this problem, dma_map_single() is called after these accesses.
> 
> Signed-off-by: Jia-Ju Bai <baijiaju@tsinghua.edu.cn>

'adapter' is accessed everywhere, in the entire driver, not just here
in the probe function.