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Date:   Mon, 17 Aug 2020 15:42:24 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Sang Yan <sangyan@huawei.com>
Cc:     kexec@lists.infradead.org, ebiederm@xmission.com,
        linux-kernel@vger.kernel.org, xiexiuqi@huawei.com,
        guohanjun@huawei.com, zhuling8@huawei.com, luanjianhai@huawei.com,
        luchunhua@huawei.com
Subject: Re: [PATCH 1/2] kexec: Add quick kexec support for kernel
Message-ID: <20200817134224.GA8381@bug>
References: <20200814055239.47348-1-sangyan@huawei.com>
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Hi!

> +config QUICK_KEXEC
> +	bool "Support for quick kexec"
> +	depends on KEXEC_CORE
> +	help
> +	  Say y here to enable this feature.

?

> +	  It use reserved memory to accelerate kexec, just like crash

uses

> +	  kexec, load new kernel and initrd to reserved memory, and
> +	  boot new kernel on that memory. It will save the time of
> +	  relocating kernel.

loads a new.... boots new... 

>  	IORES_DESC_DEVICE_PRIVATE_MEMORY	= 6,
>  	IORES_DESC_RESERVED			= 7,
>  	IORES_DESC_SOFT_RESERVED		= 8,
> +#ifdef CONFIG_QUICK_KEXEC
> +	IORES_DESC_QUICK_KEXEC			= 9,
> +#endif
>  };

Remove ifdef.

>  /*
> diff --git a/include/linux/kexec.h b/include/linux/kexec.h
> index 9e93bef52968..976bf9631070 100644
> --- a/include/linux/kexec.h
> +++ b/include/linux/kexec.h
> @@ -269,9 +269,12 @@ struct kimage {
>  	unsigned long control_page;
>  
>  	/* Flags to indicate special processing */
> -	unsigned int type : 1;
> +	unsigned int type : 2;
>  #define KEXEC_TYPE_DEFAULT 0
>  #define KEXEC_TYPE_CRASH   1
> +#ifdef CONFIG_QUICK_KEXEC
> +#define KEXEC_TYPE_QUICK   2
> +#endif
>  	unsigned int preserve_context : 1;

Here, too.

> +++ b/include/uapi/linux/kexec.h
> @@ -12,6 +12,9 @@
>  /* kexec flags for different usage scenarios */
>  #define KEXEC_ON_CRASH		0x00000001
>  #define KEXEC_PRESERVE_CONTEXT	0x00000002
> +#ifdef CONFIG_QUICK_KEXEC
> +#define KEXEC_QUICK		0x00000004
> +#endif
>  #define KEXEC_ARCH_MASK		0xffff0000

And here.

									Pavel