Messages in this thread | | | Subject | Re: [PATCH] xen-swiotlb: exchange memory with Xen only when pages are contiguous | From | Joe Jin <> | Date | Fri, 26 Oct 2018 07:48:09 -0700 |
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On 10/26/18 1:54 AM, Dongli Zhang wrote: > If dom0 (or any domain) is happy, although it could try to exchange all its > continuous dma pages back to xen hypervisor. From the perspective of each > domain, they always would like to keep as much continuous dma page as possible. > > I am thinking something different. If there is malicious domU keep exchanging > memory and allocating continuous pages from xen hypervisor, will the > continuously dma pages be used up (sort of DoS attack)?
This is a problem.
> > I am not sure if there is anything in xen hypervisor to prevent such behavior?
I'm not sure but I guess it hard to prevent it, xen hypervisor could not identify if the requirement is reasonable or no.
Maybe Xen reserve some low memory for guest start?
Thanks, Joe
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