Re: "Iomem mapping not permitted" during windows crash dump under GPLPV

[Paul Durrant <paul.durrant@citrix.com>]

James Harper wrote:
>> Keir Fraser wrote:
>>> On 30/01/2010 08:30, "James Harper" <james.harper@bendigoit.com.au>
> wrote:
>>>> So there is definitely nothing I could tell Xen to do with a DomU
> PFN
>>>> that would remove the p2m mapping?
>>> If you balloon out a page, that would do it.
>>>
>> Yes, it certainly would and I've seen it many times. I'm fairly sure
>> that by just ignoring the failed block writes coming back from
>> blkback/tap and carrying on you still end up with a usable MEMORY.DMP
>> after reboot.
>>
> 
> Yes, that works. I still eye the error messages with contempt though :)
> 

If you wanted to be clean, I guess you could check the data buffer addr 
passed to you by Windows against a map of ballooned out pages and 
substitute a dummy buffer in this case... but then you have the 
'interesting' problem of making the dump driver aware of that map.

   Paul

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Paul Durrant, Software Engineer

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