Thanks for the report @phausman! I've checked mainline and there's a
commit that matches your report, we should try this one: 9adebac37e7d
("qede: Handle infinite driver spinning for Tx timestamp.") [0].This is present in Eoan and Focal, but not in Bionic/Disco. After we confirm this is the fix we can proceed with the SRU - in case this patch doesn't help to alleviate the problem, then Eoan/Focal will be targeted too and we'll need to think in a proper solution. Notice Xenial GA kernel (v4.4) does not have PTP support in qede driver, so this issue doesn't apply to Xenial (and once it's fixed in Bionic it'll reach organically Xenial-HWE kernel). I'll work in building a 4.15 kernel for Bionic with the aforementioned fix, in order you can test. Cheers, Guilherme [0] http://git.kernel.org/linus/9adebac37e7d -- 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/1855409 Title: qede driver causes 100% CPU load Status in linux package in Ubuntu: New Status in linux source package in Xenial: Invalid Status in linux source package in Bionic: Confirmed Status in linux source package in Disco: Confirmed Status in linux source package in Eoan: New Status in linux source package in Focal: New Bug description: This bug is similar to #1832082 (bnx2x driver causes 100% CPU load) but applies for qede driver instead of bnx2x. The symptoms are the same: With chrony installed, and configured with "hwtimestamp *", I observe 100% CPU load on 2 CPU cores. Running perf report shows that kernel is busy executing qede_ptp_task function in qede driver. A workaround is to disable "hwtimestamp *" in chrony configuration. --- $ modinfo qede filename: /lib/modules/4.15.0-72-generic/kernel/drivers/net/ethernet/qlogic/qede/qede.ko version: 8.10.10.21 license: GPL description: QLogic FastLinQ 4xxxx Ethernet Driver srcversion: D5EC89D815FC81B973EE9F0 alias: pci:v00001077d00008090sv*sd*bc*sc*i* alias: pci:v00001077d00008070sv*sd*bc*sc*i* alias: pci:v00001077d00001664sv*sd*bc*sc*i* alias: pci:v00001077d00001656sv*sd*bc*sc*i* alias: pci:v00001077d00001654sv*sd*bc*sc*i* alias: pci:v00001077d00001644sv*sd*bc*sc*i* alias: pci:v00001077d00001636sv*sd*bc*sc*i* alias: pci:v00001077d00001666sv*sd*bc*sc*i* alias: pci:v00001077d00001634sv*sd*bc*sc*i* depends: ptp,qed retpoline: Y intree: Y name: qede vermagic: 4.15.0-72-generic SMP mod_unload signat: PKCS#7 signer: sig_key: sig_hashalgo: md4 parm: debug: Default debug msglevel (uint) $ uname -a Linux dcn1-clm-inf-1 4.15.0-72-generic #81-Ubuntu SMP Tue Nov 26 12:20:02 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux $ lspci | grep -i ether 19:00.0 Ethernet controller: QLogic Corp. FastLinQ QL41000 Series 10/25/40/50GbE Controller (rev 02) 19:00.1 Ethernet controller: QLogic Corp. FastLinQ QL41000 Series 10/25/40/50GbE Controller (rev 02) 19:00.2 Ethernet controller: QLogic Corp. FastLinQ QL41000 Series 10/25/40/50GbE Controller (rev 02) 19:00.3 Ethernet controller: QLogic Corp. FastLinQ QL41000 Series 10/25/40/50GbE Controller (rev 02) # perf report snippet: Children Self Command Shared Object - 44.76% 0.00% kworker/16:5 [kernel.kallsyms] ret_from_fork - kthread - 44.74% worker_thread - 44.57% process_one_work - 42.67% qede_ptp_task - 38.86% qed_ptp_hw_read_tx_ts qed_rd - 3.03% queue_work_on - 2.06% __queue_work - 0.68% get_work_pool - 0.61% radix_tree_lookup __radix_tree_lookup 0.50% set_work_pool_and_clear_pending To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1855409/+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
