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Date:   Thu, 19 May 2022 08:48:44 -0700
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Subject: Re: [PATCH net v2] net: wireless: marvell: mwifiex: fix sleep in
 atomic context bugs
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To:     <duoming@zju.edu.cn>, Kalle Valo <kvalo@kernel.org>
CC:     <linux-kernel@vger.kernel.org>, <amitkarwar@gmail.com>,
        <ganapathi017@gmail.com>, <sharvari.harisangam@nxp.com>,
        <huxinming820@gmail.com>, <davem@davemloft.net>,
        <edumazet@google.com>, <kuba@kernel.org>, <pabeni@redhat.com>,
        <linux-wireless@vger.kernel.org>, <netdev@vger.kernel.org>
References: <20220519135345.109936-1-duoming@zju.edu.cn>
 <87zgjd1sd4.fsf@kernel.org>
 <699e56d5.22006.180dce26e02.Coremail.duoming@zju.edu.cn>
From:   Jeff Johnson <quic_jjohnson@quicinc.com>
In-Reply-To: <699e56d5.22006.180dce26e02.Coremail.duoming@zju.edu.cn>
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On 5/19/2022 8:14 AM, duoming@zju.edu.cn wrote:
> Hello,
> 
> On Thu, 19 May 2022 17:58:47 +0300 Kalle Valo wrote:
> 
>>> There are sleep in atomic context bugs when uploading device dump
>>> data on usb interface. The root cause is that the operations that
>>> may sleep are called in fw_dump_timer_fn which is a timer handler.
>>> The call tree shows the execution paths that could lead to bugs:
>>>
>>>     (Interrupt context)
>>> fw_dump_timer_fn
>>>    mwifiex_upload_device_dump
>>>      dev_coredumpv(..., GFP_KERNEL)

just looking at this description, why isn't the simple fix just to 
change this call to use GFP_ATOMIC?