On Wed, Nov 15, 2006 at 12:57:24AM +0000, Paul Brook wrote: > > It isn't always system memory. Some DMA controllers deliberately write to > device FIFOs. There are also several devices which map areas of onboard RAM. > At minimum you need to make those to use RAM mappings rather than MMIO.
I'm not suggesting that we change all existing users of cpu_physical_* to a new interface that only accessed RAM. However, for cases where it is obvious that only system RAM is intended (e.g., rtl8139), it makes sense to bypass MMIO handlers. > If a device is recursively writing to itself I'd take this as sign that the > guest OS is already pretty screwed. I'm not sure what happens in this > situation on real hardware, but I wouldn't be surprised if it caused similar > effects by flooding the bus. The scenario here is a compromised guest attempting to harm a host such as Xen. Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} <[EMAIL PROTECTED]> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt _______________________________________________ Qemu-devel mailing list Qemu-devel@nongnu.org http://lists.nongnu.org/mailman/listinfo/qemu-devel
