(In reply to Klaus Mueller from comment #530) > Hmm, if rev. 1 doesn't support MWAIT - why can it be a problem anyway > at the same time which must be fixed by disabling the usage of MWAIT? > I seem to miss something?
That's a good question but, frankly, I don't have a very exact answer to it right now. In order to understand what's *really* going on in the cstate detection code one would need to instrument at least acpi_processor_get_power_info_cst() and acpi_processor_ffh_cstate_probe() to figure out what exactly does the kernel parse from those CST objects and what it uses to try to enter idle. And do all that instrumentation on an affected system. My current suspicion is is that it tries to enter idle with misconfigured states and under certain conditions, it misses the wakeup, leading to the stall. This is all a conjecture anyway. Now my patch simply falls back to the good old idle entry on AMD where we simply do HLT and we won't even attempt to enter idle the ACPI way. Makes sense? -- 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
