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From: Amerigo Wang <amwang@redhat.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org,
	Neil Horman <nhorman@redhat.com>,
	Andi Kleen <andi@firstfloor.org>,
	akpm@linux-foundation.org, Ingo Molnar <mingo@elte.hu>
Subject: Re: [RFC Patch 1/2] kexec: show memory info in /proc/iomem
Date: Wed, 12 Aug 2009 09:17:32 +0800	[thread overview]
Message-ID: <4A82182C.1080501@redhat.com> (raw)
In-Reply-To: <m163cub067.fsf@fess.ebiederm.org>

Eric W. Biederman wrote:
> Amerigo Wang <amwang@redhat.com> writes:
>
>   
>> This patch implements showing kexec memory area via /proc/iomem.
>> For example, with this patch we can see:
>>
>> # cat /proc/iomem
>> ...
>> 00100000-7ffeffff : System RAM
>>   01000000-012e1424 : Kernel code
>>   012e1425-015f1aff : Kernel data
>>   0166b000-01b4b88f : Kernel bss
>>   02000000-083fffff : Crash kernel
>>     02000000-028fffff : Used
>>     02900000-083fffff : Unused
>> ...
>>
>> So that user can know how much memory the kernel uses for crash kernel.
>>     
>
> Nacked-by: "Eric W. Biederman" <ebiederm@xmission.com>
>
> We can inspect the image we are going to load to get this information.
> In fact /sbin/kexec already inspects the image we are going to load
> to get this information.  Putting this in the kernel adds kernel
> complexity for no gain.
>   

/sbin/kexec is supported to know this, of course. But this is not for 
/sbin/kexec, this is for user (or other programs) to observe the memory 
information, so that he can know the memory he reserved is too much or not.

Without this, it is a little hard to use patch 2/2.


  reply	other threads:[~2009-08-12  1:15 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-08-11 10:39 [RFC Patch 1/2] kexec: show memory info in /proc/iomem Amerigo Wang
2009-08-11 10:39 ` [RFC Patch 2/2] kexec: allow to shrink reserved memory Amerigo Wang
2009-08-11 10:46   ` Neil Horman
2009-08-11 20:55     ` Yu, Fenghua
2009-08-12  1:32     ` Amerigo Wang
2009-08-11 19:57   ` Eric W. Biederman
2009-08-12  1:25     ` Amerigo Wang
2009-08-12  1:46       ` Eric W. Biederman
2009-08-12  2:08         ` Amerigo Wang
2009-08-12  2:43           ` Eric W. Biederman
2009-08-12  3:14             ` Amerigo Wang
2009-08-11 19:49 ` [RFC Patch 1/2] kexec: show memory info in /proc/iomem Eric W. Biederman
2009-08-12  1:17   ` Amerigo Wang [this message]
2009-08-12  1:51     ` Eric W. Biederman
2009-08-12  2:15       ` Amerigo Wang
2009-08-12  2:39         ` Eric W. Biederman
2009-08-11 20:50 ` Yu, Fenghua
2009-08-12  1:27   ` Amerigo Wang

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