On 9/3/20 2:26 PM, Paolo Bonzini wrote: > On 03/09/20 13:08, Philippe Mathieu-Daudé wrote: >> Do not allow PCI slaves to write to indirect memory >> regions such MMIO. >> >> This fixes LP#1886362 and LP#1888606. > > What is a "PCI slave"?
TBH I at a quick look at the PCIe SPEC, but not PCI. PCIe might be able to check the requester_id to check if the access is valid, but I'm not sure where to add this check. > Which devices would still be allowed to write? As of this patch, all the non-PCI, but I plan to add a similar check for USB on top of this series. > I'm worried that there are cases of MMIO reads that would be broken. > They are certainly niche these days, but they should still work; the > most "famous" one is perhaps the old BASIC > > DEF SEG=&HB800 > BLOAD "picture.pic", 0 This looks like ISA stuff. I don't think ISA does such checks (and didn't plan to add them there) but I'd need to verify. Do you have an acceptance test? > > Paolo >
