Re: changeset 22526:7a5ee3800417

[George Dunlap <george.dunlap@citrix.com>]

Hmm, yeah, that's obviously not right!  Let me take a look...

 -George

On Mon, 2011-03-07 at 09:55 +0000, 张鹏飞 wrote:
> Hi,
>     Recently, I did a research on the p2m and EPT,and did apply your
> patch(22526) to the source code of mine. But there is one place
> confused me:
> 
> 
>     
> ept_entry = table + index;
> 1.91  
>     1.92 -        ept_entry->emt = epte_get_entry_emt(d, gfn, mfn, &ipat, direct_mmio);
>     1.93 -        ept_entry->ipat = ipat;
>     1.94 -        ept_entry->sp = i ? 1 : 0;
>     1.95 -        ept_entry->avail1 = p2mt;
>     1.96 -        ept_entry->avail2 = 0;
>     1.97 +        new_entry.emt = epte_get_entry_emt(d, gfn, mfn, &ipat, direct_mmio);
>     1.98 +        new_entry.ipat = ipat;
>     1.99 +        new_entry.sp = i ? 1 : 0;
>    1.100 +        new_entry.avail1 = p2mt;
>    1.101 +        new_entry.avail2 = 0;
>    1.102  
>    1.103 -        if ( ept_entry->mfn == mfn_x(mfn) )
>    1.104 +        if ( new_entry.mfn == mfn_x(mfn) )
>    1.105               need_modify_vtd_table = 0;
>    1.106          else /* the caller should take care of the previous page */
>    1.107 -            ept_entry->mfn = mfn_x(mfn);
>    1.108 +            new_entry.mfn = mfn_x(mfn);
> 
> I think, The new_entry.mfn is used without assigned any value. Maybe there was something else I did not think of.
> Thank you for your kindness!
> 
> http://xenbits.xen.org/xen-unstable.hg/rev/7a5ee3800417