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Message-ID: <a74c86e2d6a7272d206ba44e40d69f48a25be4c1.camel@sipsolutions.net>
Subject: Re: [PATCH v6 1/2] devcoredump: remove the useless gfp_t parameter
 in dev_coredumpv and dev_coredumpm
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Duoming Zhou <duoming@zju.edu.cn>, linux-kernel@vger.kernel.org,
        linux-wireless@vger.kernel.org, briannorris@chromium.org
Cc:     amitkarwar@gmail.com, ganapathi017@gmail.com,
        sharvari.harisangam@nxp.com, huxinming820@gmail.com,
        kvalo@kernel.org, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org,
        gregkh@linuxfoundation.org, rafael@kernel.org
Date:   Fri, 10 Jun 2022 15:25:42 +0200
In-Reply-To: <df72af3b1862bac7d8e793d1f3931857d3779dfd.1654569290.git.duoming@zju.edu.cn>
References: <cover.1654569290.git.duoming@zju.edu.cn>
         <df72af3b1862bac7d8e793d1f3931857d3779dfd.1654569290.git.duoming@zju.edu.cn>
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On Tue, 2022-06-07 at 11:26 +0800, Duoming Zhou wrote:
> The dev_coredumpv() and dev_coredumpm() could not be used in atomic
> context, because they call kvasprintf_const() and kstrdup() with
> GFP_KERNEL parameter. The process is shown below:
>=20
> dev_coredumpv(.., gfp_t gfp)
>   dev_coredumpm(.., gfp_t gfp)
>     dev_set_name
>       kobject_set_name_vargs
>         kvasprintf_const(GFP_KERNEL, ...); //may sleep
>           kstrdup(s, GFP_KERNEL); //may sleep
>=20
> This patch removes gfp_t parameter of dev_coredumpv() and dev_coredumpm()
> and changes the gfp_t parameter of kzalloc() in dev_coredumpm() to
> GFP_KERNEL in order to show they could not be used in atomic context.
>=20
> Fixes: 833c95456a70 ("device coredump: add new device coredump class")
> Signed-off-by: Duoming Zhou <duoming@zju.edu.cn>
> Reviewed-by: Brian Norris <briannorris@chromium.org>

Sorry I've been buried in WiFi 7 (and kind of still am...)

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>

johannes