Re: [BISECTED]: Kernel panic (was: Linux 5.7-rc2)

[Dave Kleikamp <dave.kleikamp@oracle.com>]

On 4/22/20 4:02 AM, Giovanni Gherdovich wrote:
> Linus, Peter:
> 
> the panic seen by Harald Arnesen (and Dave Kleikamp) is unrelated to
> virtualization, and happens on all machines that have a CPU with less than 4
> physical cores. It's a very serious (and very stupid) bug in the original
> version of my code and is fixed by patch 2/4 "x86, sched: Account for CPUs
> with less than 4 cores in freq. invariance" in the series 
> 
> https://lore.kernel.org/lkml/20200416054745.740-1-ggherdovich@suse.cz
> 
> Harald, Dave:
> 
> for peace of mind, can you please share the output of
> 
>   turbostat --interval 1 sleep 0

This is a Lenovo T410.

turbostat version 20.03.20 - Len Brown <lenb@kernel.org>
CPUID(0): GenuineIntel 0xb CPUID levels; 0x80000008 xlevels; family:model:stepping 0x6:25:5 (6:37:5)
CPUID(1): SSE3 MONITOR SMX EIST TM2 TSC MSR ACPI-TM HT TM
CPUID(6): APERF, TURBO, DTS, No-PTM, No-HWP, No-HWPnotify, No-HWPwindow, No-HWPepp, No-HWPpkg, No-EPB
cpu0: MSR_IA32_MISC_ENABLE: 0x00850089 (TCC EIST MWAIT PREFETCH TURBO)
CPUID(7): No-SGX
cpu0: MSR_MISC_PWR_MGMT: 0x00400000 (ENable-EIST_Coordination DISable-EPB DISable-OOB)
cpu0: MSR_PLATFORM_INFO: 0x90020011200
9 * 133.3 = 1200.0 MHz max efficiency frequency
18 * 133.3 = 2399.9 MHz base frequency
cpu0: MSR_IA32_POWER_CTL: 0x00000000 (C1E auto-promotion: DISabled)
cpu0: MSR_TURBO_RATIO_LIMIT: 0x00001416
20 * 133.3 = 2666.6 MHz max turbo 2 active cores
22 * 133.3 = 2933.3 MHz max turbo 1 active cores
cpu0: MSR_PKG_CST_CONFIG_CONTROL: 0x00000403 (UNlocked, pkg-cstate-limit=3 (pc6))
current_driver: intel_idle
current_governor_ro: menu
cpu0: POLL: CPUIDLE CORE POLL IDLE
cpu0: C1: MWAIT 0x00
cpu0: C1E: MWAIT 0x01
cpu0: C3: MWAIT 0x10
cpu0: C6: MWAIT 0x20
cpu0: cpufreq driver: acpi-cpufreq
cpu0: cpufreq governor: ondemand
cpufreq boost: 1
cpu0: MSR_IA32_TEMPERATURE_TARGET: 0x00690a00 (105 C)
0.001871 sec
Node	Core	CPU	Avg_MHz	Busy%	Bzy_MHz	TSC_MHz	IRQ	SMI	POLL	C1	C1E	C3	C6	POLL%	C1%	C1E%	C3%	C6%	CPU%c1	CPU%c3	CPU%c6	CoreTmp	Pkg%pc3	Pkg%pc6
-	-	-	395	26.14	1493	2430	12	0	0	1	1	10	0	0.00	1.50	0.59	73.54	0.00	28.45	45.41	0.00	63	0.00	0.00
-1	0	0	239	16.27	1473	2397	3	0	0	1	0	2	0	0.00	5.92	0.00	79.10	0.00	51.50	32.23	0.00	62	0.00	0.00
-1	0	1	784	50.12	1574	2385	3	0	0	0	1	2	0	0.00	0.00	2.37	47.20	0.00	17.26
-1	2	2	171	10.80	1598	2373	2	0	0	0	0	2	0	0.00	0.00	0.00	90.00	0.00	30.33	58.88	0.00	63
-1	2	3	358	27.42	1319	2377	4	0	0	0	0	4	0	0.00	0.00	0.00	72.18	0.00	14.64