[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Qemu-devel] [Bug 1318091] Re: Perfctr MSRs not available to Guest OS on
From: |
Launchpad Bug Tracker |
Subject: |
[Qemu-devel] [Bug 1318091] Re: Perfctr MSRs not available to Guest OS on AMD Phenom II |
Date: |
Sun, 31 Dec 2017 04:17:27 -0000 |
[Expired for QEMU because there has been no activity for 60 days.]
** Changed in: qemu
Status: Incomplete => Expired
--
You received this bug notification because you are a member of qemu-
devel-ml, which is subscribed to QEMU.
https://bugs.launchpad.net/bugs/1318091
Title:
Perfctr MSRs not available to Guest OS on AMD Phenom II
Status in QEMU:
Expired
Bug description:
The AMD Phenom(tm) II X4 965 Processor (family 16, model 4, stepping
3) has the 4 architecturally supported perf counters at MSRs. The
selectors are c001000-c001003, and the counters are c001004-c001007.
I've verified that the MSRs are there and working by manually setting
the MSRs with msr-tools to count cycles.
The processor does not support the extended perfctr or the perfctr_nb.
These are in cpuid leaf 8000_0001. Qemu also sees that these cpuid
flags are not set, when I try launching with -cpu
host,perfctr_core,check. However, this flag is only for the extended
perfctr MSRs, which also happen to map the original four counters at
c0010200.
When I run a Guest OS, that OS is unable to use the perf counter
registers from c001000-7. rdmsr and wrmsr complete, but the results
are always 0. By contrast, a wrmsr to one of the c0010200 registers
causes a general protection fault (as it should, since those aren't
supported).
Kernel: 3.14.0-gentoo
Qemu: 2.0.0 (gentoo) and also with 2.0.50 (commit 06b4f00d5)
Qemu command: qemu-system-x86_64 -enable-kvm -cpu host -smp 8 -m 1024
-nographic -monitor /dev/pts/4 mnt/hdd.img
cat /proc/cpuinfo:
processor : 3
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 965 Processor
stepping : 3
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
initial apicid : 3
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb
rdtscp lm 3dnowext 3dnow constant_tsc rep_good nopl nonstop_tsc extd_apicid pni
monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a
misalignsse 3dnowprefetch osvw ibs skinit wdt hw_pstate npt lbrv svm_lock
nrip_save
bogomips : 6803.79
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate
thanks.
To manage notifications about this bug go to:
https://bugs.launchpad.net/qemu/+bug/1318091/+subscriptions
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- [Qemu-devel] [Bug 1318091] Re: Perfctr MSRs not available to Guest OS on AMD Phenom II,
Launchpad Bug Tracker <=