> From: Luck, Tony <tony.luck@xxxxxxxxx> > Sent: Wednesday, July 5, 2023 11:22 PM > ... > Subject: RE: [PATCH v2] EDAC/i10nm: shift exponent is negative > > >> # head /proc/cpuinfo > > This shows your system is the workstation version of Sapphire rapids. I don't > think we did any validation of the EDAC driver against this model. No, we didn't do any validation of the EDAC on Sapphires Rapids workstations. >From the link below, we know this is a Sapphire Rapids workstation with only 2 memory controllers. https://www.intel.com/content/www/us/en/products/sku/233480/intel-xeon-w32435-processor-22-5m-cache-3-10-ghz/specifications.html We only did validation on the Sapphire Rapids servers which were with 4 memory controllers per socket before. > > # dmidecode -t 17 > > You have just one 16GB DIMM, and EDAC found that. So despite the messy > warnings, EDAC should be working for you. > > > # lspci > > I didn't dig into this. Qiuxu - can you compare this against a server Sapphire > rapids? > Maybe it has some clues so the EDAC driver will know not to look for non- > existent memory controllers. This Sapphire Rapids workstation had 2 memory controllers but appeared 4 memory controller PCIe devices from the log: 0000:fe:0c.0 1101: 8086:324a 0000:fe:0d.0 1101: 8086:324a // absent mc fooling the driver, should not appear 0000:fe:0e.0 1101: 8086:324a 0000:fe:0f.0 1101: 8086:324a // absent mc fooling the driver, should not appear By observing that the MMIO registers of these absent memory controllers consistently hold the value of ~0. We may identify a memory controller as absent by checking if its MMIO register "mcmtr" == ~0 in all its channels. I made a patch below to skip all these absent memory controllers https://lore.kernel.org/linux-edac/20230706134216.37044-1-qiuxu.zhuo@xxxxxxxxx/T/#u @Koba Ko, could you please verify the patch from the link above on your workstation? Thanks! BTW, Kai-Heng Feng also found the same issue before: https://lore.kernel.org/linux-edac/CAAd53p41Ku1m1rapeqb1xtD+kKuk+BaUW=dumuoF0ZO3GhFjFA@xxxxxxxxxxxxxx/T/#m5de16dce60a8c836ec235868c7c16e3fefad0cc2 - Qiuxu
