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Message-ID: <7287f315-0ac9-eef1-850f-8d8a91effe3d@intel.com>
Date:   Tue, 11 Apr 2023 16:12:55 -0700
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Subject: Re: [PATCH V2,net-next, 3/3] net: mana: Add support for jumbo frame
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To:     Haiyang Zhang <haiyangz@microsoft.com>,
        <linux-hyperv@vger.kernel.org>, <netdev@vger.kernel.org>
CC:     <decui@microsoft.com>, <kys@microsoft.com>,
        <paulros@microsoft.com>, <olaf@aepfle.de>, <vkuznets@redhat.com>,
        <davem@davemloft.net>, <wei.liu@kernel.org>, <edumazet@google.com>,
        <kuba@kernel.org>, <pabeni@redhat.com>, <leon@kernel.org>,
        <longli@microsoft.com>, <ssengar@linux.microsoft.com>,
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        <ast@kernel.org>, <sharmaajay@microsoft.com>, <hawk@kernel.org>,
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References: <1680901196-20643-1-git-send-email-haiyangz@microsoft.com>
 <1680901196-20643-4-git-send-email-haiyangz@microsoft.com>
From:   Jacob Keller <jacob.e.keller@intel.com>
In-Reply-To: <1680901196-20643-4-git-send-email-haiyangz@microsoft.com>
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On 4/7/2023 1:59 PM, Haiyang Zhang wrote:
> During probe, get the hardware-allowed max MTU by querying the device
> configuration. Users can select MTU up to the device limit.
> When XDP is in use, limit MTU settings so the buffer size is within
> one page.
> Also, to prevent changing MTU fails, and leaves the NIC in a bad state,
> pre-allocate all buffers before starting the change. So in low memory
> condition, it will return error, without affecting the NIC.
> 

What happens if XDP gets enabled after MTU larger than PAGE_SIZE is set?
Will XDP fail to enable in that case?

Thanks,
Jake