On Thu, May 11, 2023 at 11:22 AM Marek Marczykowski-Górecki <[email protected]> wrote: > > On Thu, May 11, 2023 at 10:58:48AM -0400, Jason Andryuk wrote: > > On Fri, May 5, 2023 at 5:26 PM Marek Marczykowski-Górecki > > <[email protected]> wrote: > > > > > > On older systems, XHCI xcap had a layout that no other (interesting) > > > registers > > > were placed on the same page as the debug capability, so Linux was fine > > > with > > > making the whole page R/O. But at least on Tiger Lake and Alder Lake, > > > Linux > > > needs to write to some other registers on the same page too. > > > > > > Add a generic API for making just parts of an MMIO page R/O and use it to > > > fix > > > USB3 console with share=yes or share=hwdom options. More details in commit > > > messages. > > > > > > Marek Marczykowski-Górecki (2): > > > x86/mm: add API for marking only part of a MMIO page read only > > > drivers/char: Use sub-page ro API to make just xhci dbc cap RO > > > > Series: > > Tested-by: Jason Andryuk <[email protected]> > > > > I had the issue with a 10th Gen, Comet Lake, laptop. With an HVM > > usbvm with dbgp=xhci,share=1, Xen crashed the domain because of: > > (XEN) d1v0 EPT violation 0xdaa (-w-/r-x) gpa 0x000000f1008470 mfn 0xcc328 > > type 5 > > Hmm, this series is supposed to avoid exactly this issue. I tested it on > 12th Gen, so maybe 10th Gen has a bit different layout. > Can you add a debug print before subpage_mmio_ro_add() call in > xhci-dbc.c and see what area is getting protected?
Your series fixes the problem! I just had the details from the original issue, so I included them. I was trying to highlight what this series fixed for me. Sorry for the confusion. Regards, Jason
