Re: [PATCH] x86: only put e820 ram entries in resource tree

[ebiederm@xmission.com (Eric W. Biederman)]

Yinghai Lu <yhlu.kernel@gmail.com> writes:

> may need user to have new kexec tools that could create e820 table
> from /sys/firmware/memmap instead of /proc/iomem for second kernel

Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com>

/proc/iomem is mostly about io resources which you have just removed.
It is totally the wrong thing to only register RAM resource!

The use by kexec was and is just taking advantage of something that
already existed.

Eric

> Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
> Cc: Bernhard Walle <bwalle@suse.de>
> Cc: Vivek Goyal <vgoyal@redhat.com>
> Cc: "Eric W. Biederman" <ebiederm@xmission.com>
>
> Index: linux-2.6/arch/x86/kernel/e820.c
> ===================================================================
> --- linux-2.6.orig/arch/x86/kernel/e820.c
> +++ linux-2.6/arch/x86/kernel/e820.c
> @@ -1279,6 +1279,10 @@ void __init e820_reserve_resources(void)
>  
>  	res = alloc_bootmem_low(sizeof(struct resource) * e820.nr_map);
>  	for (i = 0; i < e820.nr_map; i++) {
> +		if (e820.map[i].type != E820_RAM) {
> +			res++;
> +			continue;
> +		}
>  		end = e820.map[i].addr + e820.map[i].size - 1;
>  #ifndef CONFIG_RESOURCES_64BIT
>  		if (end > 0x100000000ULL) {