[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] [PATCH v4 1/4] xen/arm: observe itargets setting in vgic_enable_irqs and vgic_disable_irqs



On 06/09/2014 01:04 PM, Stefano Stabellini wrote:
> On Mon, 9 Jun 2014, Julien Grall wrote:
>> On 06/09/2014 11:47 AM, Stefano Stabellini wrote:
>>>> Write in GICD_ITARGETSR can be either half-word or word. If I'm not 
>>>> mistaken
>>>> you sanity check only handle word access.
>>>
>>> I realize that it is a bit tricky to read, but this works for both word
>>> and half-word accesses.

Hmmm... I meant byte access not half-word. Sorry.

>> I think you have to mask the unused bits in the register. We can't
>> assume that they will be all-zeroed.
> 
> That's a good hint but I already pass 32 to find_next_bit as max bit to
> search for. The rest is ignored.
> 

So if the byte is equal 0, then you can reach a one bit in the unused
part...

-- 
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.