I assume there is several (at least two) similar problems that cause spontaneous system hangs.
One of them is mwait bug listed in AMD errata. Looks like idle=halt is partial workaround for this. But, as said in AMD community forum, guest OS in virtual machine may execute mait instruction and provoke this bug. Luckily, mwait is not common for user-space applications (still not sure about that). Another is power supply problem. This may be caused by unsupported PSU (no 0A 12V) or unsuitable power subsystem on motherboard. This may be partially (again!) solved by BIOS "typical current idle" option or disabling C6 states by .py script. IMO this bios option may be implemented not properly in some mobos firmware. Looks like it only "says to OS" do not use C-states, but does not prevent deep sleep on hw level. Here we got [Firmware Bug]: ACPI MWAIT C-state 0x0 not supported by HW (0x0) in dmesg and problem persists. Have read some forums with assures of completely stable Ryzen systems work under Linux without any tweks. So not really too many systems affected by mwait and PSU lockups. I think some combination of factors may provoke this behavior. Mobo+PSU, memory latency (why not?) or some vendor-provided bios config. Also in some cases these two problems may appear together. Obviously, segfaults or amdgpu crashes is not related to this bug. PS:Sorry for my bad English. -- 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/1690085 Title: Ryzen 1800X freeze - rcu_sched detected stalls on CPUs/tasks Status in Linux: Confirmed Status in linux package in Ubuntu: Confirmed Bug description: Hi, We aregetting various kernel crash on a pretty new config. We're using Ryzen 1800X CPU with X370 Gaming Pro Carbon MB (7A32V1) using latest BIOS available (1.52) We are running Ubuntu 17.04 (amd64), we've tried different kernel version, native one and releases from http://kernel.ubuntu.com/~kernel-ppa/mainline/ too. Tested kernel version: native 17.04 kernel 4.10.15 Issues are the same, we're getting random freeze on the machine. Here is kern.log entry when happening : May 10 22:41:56 dev2 kernel: [24366.186246] INFO: rcu_sched detected stalls on CPUs/tasks: May 10 22:41:56 dev2 kernel: [24366.187618] 0-...: (1 GPs behind) idle=49b/1/0 softirq=28561/28563 fqs=913449 May 10 22:41:56 dev2 kernel: [24366.188977] (detected by 12, t=1860207 jiffies, g=10001, c=10000, q=4656) May 10 22:41:56 dev2 kernel: [24366.190344] Task dump for CPU 0: May 10 22:41:56 dev2 kernel: [24366.190345] swapper/0 R running task 0 0 0 0x00000008 May 10 22:41:56 dev2 kernel: [24366.190348] Call Trace: May 10 22:41:56 dev2 kernel: [24366.190354] ? native_safe_halt+0x6/0x10 May 10 22:41:56 dev2 kernel: [24366.190355] ? default_idle+0x20/0xd0 May 10 22:41:56 dev2 kernel: [24366.190358] ? arch_cpu_idle+0xf/0x20 May 10 22:41:56 dev2 kernel: [24366.190360] ? default_idle_call+0x23/0x30 May 10 22:41:56 dev2 kernel: [24366.190362] ? do_idle+0x16f/0x200 May 10 22:41:56 dev2 kernel: [24366.190364] ? cpu_startup_entry+0x71/0x80 May 10 22:41:56 dev2 kernel: [24366.190366] ? rest_init+0x77/0x80 May 10 22:41:56 dev2 kernel: [24366.190368] ? start_kernel+0x464/0x485 May 10 22:41:56 dev2 kernel: [24366.190369] ? early_idt_handler_array+0x120/0x120 May 10 22:41:56 dev2 kernel: [24366.190371] ? x86_64_start_reservations+0x24/0x26 May 10 22:41:56 dev2 kernel: [24366.190372] ? x86_64_start_kernel+0x14d/0x170 May 10 22:41:56 dev2 kernel: [24366.190373] ? start_cpu+0x14/0x14 May 10 22:44:56 dev2 kernel: [24546.188093] INFO: rcu_sched detected stalls on CPUs/tasks: May 10 22:44:56 dev2 kernel: [24546.189461] 0-...: (1 GPs behind) idle=49b/1/0 softirq=28561/28563 fqs=935027 May 10 22:44:56 dev2 kernel: [24546.190823] (detected by 14, t=1905212 jiffies, g=10001, c=10000, q=4740) May 10 22:44:56 dev2 kernel: [24546.192191] Task dump for CPU 0: May 10 22:44:56 dev2 kernel: [24546.192192] swapper/0 R running task 0 0 0 0x00000008 May 10 22:44:56 dev2 kernel: [24546.192195] Call Trace: May 10 22:44:56 dev2 kernel: [24546.192199] ? native_safe_halt+0x6/0x10 May 10 22:44:56 dev2 kernel: [24546.192201] ? default_idle+0x20/0xd0 May 10 22:44:56 dev2 kernel: [24546.192203] ? arch_cpu_idle+0xf/0x20 May 10 22:44:56 dev2 kernel: [24546.192204] ? default_idle_call+0x23/0x30 May 10 22:44:56 dev2 kernel: [24546.192206] ? do_idle+0x16f/0x200 May 10 22:44:56 dev2 kernel: [24546.192208] ? cpu_startup_entry+0x71/0x80 May 10 22:44:56 dev2 kernel: [24546.192210] ? rest_init+0x77/0x80 May 10 22:44:56 dev2 kernel: [24546.192211] ? start_kernel+0x464/0x485 May 10 22:44:56 dev2 kernel: [24546.192213] ? early_idt_handler_array+0x120/0x120 May 10 22:44:56 dev2 kernel: [24546.192214] ? x86_64_start_reservations+0x24/0x26 May 10 22:44:56 dev2 kernel: [24546.192215] ? x86_64_start_kernel+0x14d/0x170 May 10 22:44:56 dev2 kernel: [24546.192217] ? start_cpu+0x14/0x14 Depending on the kernel version, we've got NMI watchdog errors related to CPU stuck (mentioning the CPU core id, which is random). Crash is happening randomly, but in general after some hours (3-4h). Now, we've installed kernel 4.11.0-041100-generic #201705041534 this morning and waiting for crash... For now, the machine is not "used", at least, it's not CPU stressed... Thanks --- ApportVersion: 2.20.4-0ubuntu4 Architecture: amd64 DistroRelease: Ubuntu 17.04 InstallationDate: Installed on 2017-05-09 (1 days ago) InstallationMedia: Ubuntu-Server 17.04 "Zesty Zapus" - Release amd64 (20170412) Package: linux (not installed) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=fr_FR.UTF-8 SHELL=/bin/bash Tags: zesty Uname: Linux 4.11.0-041100-generic x86_64 UnreportableReason: The running kernel is not an Ubuntu kernel UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1690085/+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
