I have suffered the same issue. I have found that I lost one CPU thread after upgrading amd64-microcode from `3.20191218.1ubuntu1` to `3.20191218.1ubuntu1.2`. Backporting the latest microcode resolves the issue.
OS: Ubuntu 20.04.6 LTS Release: 20.04 Kernel: 5.4.0-144-generic CPU: 2x EPYC 9654 DIMM: 24x Micron DDR5 64G lscpu log show Off-line CPU(s) info as below. Please note that my SMT is enabled but "Thread(s) per core" shows "1": Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 52 bits physical, 57 bits virtual CPU(s): 384 On-line CPU(s) list: 0-191,193-383 Off-line CPU(s) list: 192 Thread(s) per core: 1 Core(s) per socket: 96 Socket(s): 2 NUMA node(s): 2 Vendor ID: AuthenticAMD CPU family: 25 Model: 17 Model name: AMD EPYC 9654 96-Core Processor Stepping: 1 Frequency boost: enabled -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-hwe in Ubuntu. https://bugs.launchpad.net/bugs/2042888 Title: It shows 'smpboot: do_boot_cpu failed(-1) to wakeup CPU#96' in system dmesg log with kernel version 6.2.0-060200-generic. Status in linux-hwe package in Ubuntu: Confirmed Bug description: OS: Ubuntu 22.04.3 LTS Release: 22.04 Kernel: 6.2.0-060200-generic CPU: 1x EPYC 9654 DIMM: 2x Samsung DDR5 16G 1.Install Ubuntu 22.04.3 and upgrade its kernel to 6.2.0-060200-generic (also tried on kernel 6.5.7-060507) 2.Reboot system and enable SMT-Control from BIOS. 3.Boot to system to read lscpu.txt and dmesg.txt, lscpu log show Off-line CPU(s) info as below: CPU(s): 192 On-line CPU(s) list: 0-95,97-191 Off-line CPU(s) list: 96 Vendor ID: AuthenticAMD Model name: AMD EPYC 9654 96-Core Processor CPU family: 25 Model: 17 Thread(s) per core: 2 Core(s) per socket: 96 Socket(s): 1 Stepping: 1 Frequency boost: enabled dmesg log show CPU fail info as below, [ 0.360560] smp: Bringing up secondary CPUs ... [ 0.360708] x86: Booting SMP configuration: [ 0.360711] .... node #0, CPUs: #1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #12 #13 #14 #15 #16 #17 #18 #19 #20 #21 #22 #23 #24 #25 #26 #27 #28 #29 #30 #31 #32 #33 #34 #35 #36 #37 #38 #39 #40 #41 #42 #43 #44 #45 #46 #47 #48 #49 #50 #51 #52 #53 #54 #55 #56 #57 #58 #59 #60 #61 #62 #63 #64 #65 #66 #67 #68 #69 #70 #71 #72 #73 #74 #75 #76 #77 #78 #79 #80 #81 #82 #83 #84 #85 #86 #87 #88 #89 #90 #91 #92 #93 #94 #95 #96 [ 10.631524] smpboot: do_boot_cpu failed(-1) to wakeup CPU#96 [ 10.631842] #97 BTW, we also find the same bug on AMD EPYC 9534 64-Core CPU with Ubuntu 22.04.3-kernel 6.2.0 and 6.5.7. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-hwe/+bug/2042888/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
