On 06.09.2023 23:38, Elliott Mitchell wrote: > On Thu, Aug 31, 2023 at 07:52:05PM +0000, Development wrote: >> >> However, in 2009-02, "cegger" wrote MCA/MCE_in_Xen, a proposal for >> having xen start checking the information >> Xen started accessing the EDAC information (now called "MCE") at some >> point after that, which blocks the linux kernel in dom0 from accessing it. >> (I also found what appears to be related sides from a presentation from >> 2012 at: >> https://lkml.iu.edu/hypermail/linux/kernel/1206.3/01304/xen_vMCE_design_%28v0_2%29.pdf >> ) >> > > I hadn't seen that before. Clearly shows someone who had no idea what > they were doing designed it. The author was thinking "virtualize > everything!", whereas MCE is a perfect situation for paravirtualization. > Let Dom0 process MCE events (which allows use of Linux's more up to date > MCE drivers), then let Dom0 notify Xen if action is needed (a page was > corrupted, tell the effected domain). > > There was a recent proposal to simply import Linux's rather more recent > MCE/EDAC source. This hasn't happened yet. For people using Xen this > has been a very concerning issue for some time.
I'm unaware of such a proposal; do you have a reference? EDAC drivers typically are vendor- or even chipset-specific aiui. At least the latter wouldn't make them a good fit to import into Xen. Along of what you say earlier, they instead want to become Xen-aware (to deal with address translation as necessary). That'll also have better chances of things staying up-to-date. Jan
