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Message-ID: <1868cc20-fd69-f5db-9c49-30d87e74355b@infradead.org>
Date:   Thu, 1 Jun 2023 16:13:54 -0700
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Subject: Re: [PATCH v1 -next] tty: serial: add panic serial helper
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To:     Hongyu Xie <xiehongyu1@kylinos.cn>, linux@armlinux.org.uk,
        gregkh@linuxfoundation.org, jirislaby@kernel.org
Cc:     linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        xy521521@gmail.com
References: <20230531081737.423737-1-xiehongyu1@kylinos.cn>
From:   Randy Dunlap <rdunlap@infradead.org>
In-Reply-To: <20230531081737.423737-1-xiehongyu1@kylinos.cn>
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Hi--

On 5/31/23 01:17, Hongyu Xie wrote:
> diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
> index 3e3fb377d90d..70d0d2e4b827 100644
> --- a/drivers/tty/serial/Kconfig
> +++ b/drivers/tty/serial/Kconfig
> @@ -198,6 +198,31 @@ config SERIAL_KGDB_NMI
>  
>  	  If unsure, say N.
>  
> +config PANIC_SERIAL_HELPER
> +	tristate "debug through uart after panic"

	                        UART

> +	depends on PANIC_TIMEOUT=0
> +	select CONSOLE_POLL
> +	help
> +	  This is a debug module that allows you to get all kernel logs
> +	  after panic.
> +
> +	  Normally you need to attach a USB-to-UART tool or enable kdump
> +	  before panic happens to get log from kernel after panic. If you
> +	  didn't do that and kdump is not working, you can't get any log to
> +	  know what happened before panic. If you have a USB-to-UART tool
> +	  and the uart port on your computer is working, this module helps

	          UART

> +	  you to get all kernel log after panic() is called.
> +
> +	  This module uses serial port in poll mode, so it's more stable
> +	  than other debugging methods.
> +
> +	  Read <file:Documentation/dev-tools/panic_serial_helper.rst> for
> +	  usage.
> +
> +	  Say Y if you have an UART port that is working. If unsure, say N.
> +	  Say M if you want add this as a module driver.
> +	  The module will be called panic_serial_helper.

thanks.
-- 
~Randy