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Date:   Mon, 24 Apr 2023 15:17:09 +0200
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Subject: Re: [PATCH] spi: remove return value check of debugfs_create_dir()
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To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Mark Brown <broonie@kernel.org>
Cc:     Yingsha Xu <ysxu@hust.edu.cn>,
        Serge Semin <fancer.lancer@gmail.com>,
        linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230423061155.2540-1-ysxu@hust.edu.cn>
 <eb3c6aa6-6820-4e94-8eb0-5abd3b627fcc@sirena.org.uk>
 <368e31ae-31b5-839f-72e3-20a27239cb0b@sony.com>
 <a4706089-399b-4663-9ac8-216f12ebe7ca@sirena.org.uk>
 <2023042421-landowner-magnitude-a38c@gregkh>
From:   Peter Enderborg <Peter.Enderborg@sony.com>
In-Reply-To: <2023042421-landowner-magnitude-a38c@gregkh>
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On 4/24/23 14:53, Greg Kroah-Hartman wrote:
>
>>> We can do things with the debug information without filesystem enabled.
> What exactly do you mean by this?
>
>
We can read out data from kernel with a ramdumper and analyse with crash.

See https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/kernel_administration_guide/kernel_crash_dump_guide

If it is useful or not I can not say, but the dws->regset. is lost and can not be read with a post mortem debugger.


> thanks,
>
> greg k-h