From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.xen@gmail.com>
Subject: Re: [PATCH v3] xen: handle paged gfn in
 wrmsr_hypervisor_regs
Date: Fri, 03 May 2013 16:58:51 +0100
Message-ID: <CDA99D4B.23FEE%keir.xen@gmail.com>
References: <5183F44602000078000D330F@nat28.tlf.novell.com>
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To: Jan Beulich <JBeulich@suse.com>, Olaf Hering <olaf@aepfle.de>
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On 03/05/2013 16:30, "Jan Beulich" <JBeulich@suse.com> wrote:

>>          if ( idx > 0 )
>>          {
>>              gdprintk(XENLOG_WARNING,
>>                       "Out of range index %u to MSR %08x\n",
>>                       idx, 0x40000000);
>> -            return 0;
>> +            return -EINVAL;
> 
> But I'd stay away from converting to actual errors both here ...
> 
>>          }
>>  
>> -        page = get_page_from_gfn(d, gmfn, NULL, P2M_ALLOC);
>> +        page = get_page_from_gfn(d, gmfn, &t, P2M_ALLOC);
>>  
>>          if ( !page || !get_page_type(page, PGT_writable_page) )
>>          {
>>              if ( page )
>>                  put_page(page);
>> +
>> +            if ( p2m_is_paging(t) )
>> +            {
>> +                p2m_mem_paging_populate(d, gmfn);
>> +                return -EAGAIN;
>> +            }
>> +
>>              gdprintk(XENLOG_WARNING,
>>                       "Bad GMFN %lx (MFN %lx) to MSR %08x\n",
>> -                     gmfn, page_to_mfn(page), base + idx);
>> -            return 0;
>> +                     gmfn, page ? page_to_mfn(page) : -1UL, base);
>> +            return -EINVAL;
> 
> ... and here. If at all these ought to go into a separate patch
> (which we'd likely postpone until after 4.3).

But they are errors?

Could agree with postponing to post-4.3 though.

 -- Keir