Re: [Qemu-devel] [Qemu-ppc] [PATCH 1/3] ppc: Correctly handle errors reading ibm, vmx and ibm, dfp properties

[David Gibson <david@gibson.dropbear.id.au>]

On Sun, Oct 30, 2011 at 05:53:13PM +0100, Alexander Graf wrote:
> 
> On 28.10.2011, at 03:56, David Gibson wrote:
> 
> > kvmppc_read_int_cpu_dt() returns -1 on errors. However
> > kvmppc_host_cpu_def() assumes that it can use the return value
> > directly for setting the corresponding instruction support bits.  This
> > will give invalid results when kvmppc_read_int_cpu_dt() returns -1
> > (i.e. 0xffffffff).
> > 
> > In fact, it gets worse: the common case for -1 return values is when
> > the properties are simply not present.  On some machines this means
> > the features are not available but in other cases it just means that
> > the firmware on this platform does not provide this information.  So,
> > when there's an error reading the properties we really can't tell if
> > vmx or dfp is supported.
> > 
> > Therefore, this patch checks for -1 return values and falls back to
> > qemu's built in table of CPU capabilities in that case.
> > 
> > Reported-by: Nishanth Aravamudan <nacc@us.ibm.com>
> > Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> 
> I already have this patch in my tree, though with different
> author.

Yeah, I realised that not long after I sent it.

> I've added Nishanth as Reported-by on it now and you as
> Acked-by, if you're ok with that.

Ok, thanks.

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
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