Joe, I will take a look. -kim
-----Original Message----- From: boun...@canonical.com [mailto:boun...@canonical.com] On Behalf Of Joseph Salisbury Sent: Thursday, November 02, 2017 1:56 PM To: Naru, Kim <kim.n...@amd.com> Subject: [Bug 1729442] Re: Prevent timer value 0 for MWAITX I built Xenial and Zesty test kernels, both with a pick of commit 88d879d29f9cc0d. The test kernels can be downloaded from: http://kernel.ubuntu.com/~jsalisbury/lp1729442/xenial http://kernel.ubuntu.com/~jsalisbury/lp1729442/zesty Can you test this kernels and see if they resolve this bug? -- You received this bug notification because you are a member of AMD Team, which is subscribed to amd. https://bugs.launchpad.net/bugs/1729442 Title: Prevent timer value 0 for MWAITX Status in amd: New Status in linux package in Ubuntu: In Progress Status in linux source package in Xenial: In Progress Status in linux source package in Zesty: In Progress Bug description: Newer hardware has uncovered a bug in the software implementation of using MWAITX for the delay function. A value of 0 for the timer is meant to indicate that a timeout will not be used to exit MWAITX. On newer hardware this can result in MWAITX never returning, resulting in NMI soft lockup messages being printed. On older hardware, some of the other conditions under which MWAITX can exit masked this issue. The AMD APM does not currently document this and will be updated. Please refer to http://marc.info/?l=kvm&m=148950623231140 for information regarding NMI soft lockup messages on an AMD Ryzen 1800X. This has been root-caused as a 0 passed to MWAITX causing it to wait indefinitely. This change has the added benefit of avoiding the unnecessary setup of MONITORX/MWAITX when the delay value is zero. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?id=88d879d29f9cc0de2d930b584285638cdada6625 To manage notifications about this bug go to: https://bugs.launchpad.net/amd/+bug/1729442/+subscriptions -- 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/1729442 Title: Prevent timer value 0 for MWAITX Status in amd: New Status in linux package in Ubuntu: In Progress Status in linux source package in Xenial: In Progress Status in linux source package in Zesty: In Progress Bug description: Newer hardware has uncovered a bug in the software implementation of using MWAITX for the delay function. A value of 0 for the timer is meant to indicate that a timeout will not be used to exit MWAITX. On newer hardware this can result in MWAITX never returning, resulting in NMI soft lockup messages being printed. On older hardware, some of the other conditions under which MWAITX can exit masked this issue. The AMD APM does not currently document this and will be updated. Please refer to http://marc.info/?l=kvm&m=148950623231140 for information regarding NMI soft lockup messages on an AMD Ryzen 1800X. This has been root-caused as a 0 passed to MWAITX causing it to wait indefinitely. This change has the added benefit of avoiding the unnecessary setup of MONITORX/MWAITX when the delay value is zero. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/commit/?id=88d879d29f9cc0de2d930b584285638cdada6625 To manage notifications about this bug go to: https://bugs.launchpad.net/amd/+bug/1729442/+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
