On 21/09/12 15:27, Konrad Rzeszutek Wilk wrote: > On Fri, Sep 21, 2012 at 01:23:48PM +0100, David Vrabel wrote: >> >> It's not just virtual space. blkback in pvops kernels allocates its >> pages from the balloon and if there aren't enough ballooned out pages it >> has to allocate real pages (releasing the MFN back to Xen). >> >> Classic kernels didn't need to do this as there was an API for allocate >> new "empty" struct page's that get mapped into kernel space. > > Can we ressurect/implement that in the new pvops? We could use the memory > hotplug mechanism to allocate "non-existent" memory.
I don't see why not. Provided the limitations are documented I wouldn't make merging the persistent grant stuff dependent on it. David -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/