This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed- yakkety' to 'verification-done-yakkety'. If the problem still exists, change the tag 'verification-needed-yakkety' to 'verification-failed- yakkety'.
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you! ** Tags added: verification-needed-yakkety -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1579205 Title: CONFIG_NR_CPUS=256 is too low Status in linux package in Ubuntu: Fix Committed Status in linux source package in Xenial: Fix Released Status in linux source package in Yakkety: Fix Committed Bug description: Intel Knights Landing systems boot up to 272 processor cores. The stock Ubuntu Linux kernel images leave processor cores above 256 disabled: [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 256/0xeb ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 257/0xef ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 258/0xf3 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 259/0xf7 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 260/0xfb ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 261/0xff ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 262/0x103 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 263/0x107 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 264/0x10b ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 265/0x10f ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 266/0x113 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 267/0x117 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 268/0x11b ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 269/0x11f ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 270/0x123 ignored. [ 0.000000] ACPI: NR_CPUS/possible_cpus limit of 256 reached. Processor 271/0x127 ignored. I'd request an increase in CONFIG_NR_CPUS to 512. This would match Debian's default setting. For comparison, RHEL/CentOS ship with 4096. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1579205/+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