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|
user-level: 0.527
hypervisor: 0.521
risc-v: 0.521
boot: 0.481
KVM: 0.476
virtual: 0.476
device: 0.455
vnc: 0.441
TCG: 0.430
x86: 0.408
register: 0.408
mistranslation: 0.398
graphic: 0.391
ppc: 0.380
VMM: 0.378
peripherals: 0.373
performance: 0.349
architecture: 0.344
arm: 0.334
i386: 0.312
debug: 0.312
permissions: 0.307
semantic: 0.302
assembly: 0.298
PID: 0.292
network: 0.286
kernel: 0.283
socket: 0.266
files: 0.215
-cpu haswell / broadwell have no MONITOR in features1
In qemu 2.9.0 if you run
qemu-system-x86_64 -cpu Broadwell (or Haswell)
then the CPU features1 flag include the SSE3 bit, but do NOT include the MONITOR/MWAIT bit. This is so even when the host includes the features.
Additionally, running qemu in this manner results in several error messages:
warning: TCG doesn't support requested feature: CPUID.01H:ECX.fma [bit 12]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.pcid [bit 17]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.x2apic [bit 21]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.avx [bit 28]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.f16c [bit 29]
warning: TCG doesn't support requested feature: CPUID.01H:ECX.rdrand [bit 30]
warning: TCG doesn't support requested feature: CPUID.07H:EBX.hle [bit 4]
warning: TCG doesn't support requested feature: CPUID.07H:EBX.avx2 [bit 5]
warning: TCG doesn't support requested feature: CPUID.07H:EBX.invpcid [bit 10]
warning: TCG doesn't support requested feature: CPUID.07H:EBX.rtm [bit 11]
warning: TCG doesn't support requested feature: CPUID.07H:EBX.rdseed [bit 18]
warning: TCG doesn't support requested feature: CPUID.80000001H:ECX.3dnowprefetch
(Among possible other uses, the lack of the MONITOR feature bit causes NetBSD to fall-back on a
check-and-pause loop while an application CPU is waiting to be told to proceed by the boot CPU.)
Can you still reproduce this issue with the latest version of QEMU? Looking at https://git.qemu.org/?p=qemu.git;a=commitdiff;h=0723cc8a5558c94388 for example, it might have been fixed since QEMU v4.2...
This bug seems not to be a problem, and may reflect an issue with
NetBSD. Even though the decode of the features1 register does not
include MONITOR/MWAIT, that capability is separately reported on a
separate line, further down (apologies in advance for any confusing
line-wrap):
# cpuctl identify 0
cpu0: highest basic info 0000000d
cpu0: highest hypervisor info 40000001
cpu0: highest extended info 80000008
cpu0: Running on hypervisor: QEMU(TCG)
cpu0: "Intel Core Processor (Broadwell)"
cpu0: Intel Core M-5xxx, 5th gen Core (Broadwell) (686-class), 3198.24 MHz
cpu0: family 0x6 model 0x3d stepping 0x2 (id 0x306d2)
cpu0: features 0x78bfbfd<FPU,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA>
cpu0: features 0x78bfbfd<CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2>
cpu0: features1 0xced82203<SSE3,PCLMULQDQ,SSSE3,CX16,SSE41,SSE42,MOVBE,POPCNT>
cpu0: features1 0xced82203<AES,XSAVE,OSXSAVE,RDRAND,RAZ>
cpu0: features2 0x28100800<SYSCALL/SYSRET,XD,RDTSCP,EM64T>
cpu0: features3 0x21<LAHF,LZCNT>
cpu0: features5 0x180389<FSGSBASE,BMI1,SMEP,BMI2,ERMS,ADX,SMAP>
cpu0: xsave features 0x7<x87,SSE,AVX>
cpu0: xsave instructions 0x1<XSAVEOPT>
cpu0: xsave area size: current 832, maximum 832, xgetbv enabled
cpu0: enabled xsave 0x7<x87,SSE,AVX>
cpu0: I-cache 32KB 64B/line 8-way, D-cache 32KB 64B/line 8-way
cpu0: L2 cache 4MB 64B/line 16-way
cpu0: L3 cache 16MB 64B/line 16-way
cpu0: Initial APIC ID 0
cpu0: Cluster/Package ID 0
cpu0: Core ID 0
cpu0: SMT ID 0
cpu0: MONITOR/MWAIT extensions 0x3<EMX,IBE>
cpu0: monitor-line size 0
cpu0: DSPM-eax 0x4<ARAT>
cpu0: SEF highest subleaf 00000000
cpu0: Power Management features: 0
cpu0: microcode version 0x0, platform ID 0
#
On Fri, 22 May 2020, Thomas Huth wrote:
> Can you still reproduce this issue with the latest version of QEMU?
> Looking at
> https://git.qemu.org/?p=qemu.git;a=commitdiff;h=0723cc8a5558c94388 for
> example, it might have been fixed since QEMU v4.2...
>
> ** Changed in: qemu
> Status: New => Incomplete
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1693667
>
> Title:
> -cpu haswell / broadwell have no MONITOR in features1
>
> Status in QEMU:
> Incomplete
>
> Bug description:
> In qemu 2.9.0 if you run
>
> qemu-system-x86_64 -cpu Broadwell (or Haswell)
>
> then the CPU features1 flag include the SSE3 bit, but do NOT include
> the MONITOR/MWAIT bit. This is so even when the host includes the
> features.
>
>
> Additionally, running qemu in this manner results in several error messages:
>
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.fma [bit 12]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.pcid [bit 17]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.x2apic [bit 21]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.avx [bit 28]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.f16c [bit 29]
> warning: TCG doesn't support requested feature: CPUID.01H:ECX.rdrand [bit 30]
> warning: TCG doesn't support requested feature: CPUID.07H:EBX.hle [bit 4]
> warning: TCG doesn't support requested feature: CPUID.07H:EBX.avx2 [bit 5]
> warning: TCG doesn't support requested feature: CPUID.07H:EBX.invpcid [bit 10]
> warning: TCG doesn't support requested feature: CPUID.07H:EBX.rtm [bit 11]
> warning: TCG doesn't support requested feature: CPUID.07H:EBX.rdseed [bit 18]
> warning: TCG doesn't support requested feature: CPUID.80000001H:ECX.3dnowprefetch
>
>
> (Among possible other uses, the lack of the MONITOR feature bit causes NetBSD to fall-back on a
> check-and-pause loop while an application CPU is waiting to be told to proceed by the boot CPU.)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/qemu/+bug/1693667/+subscriptions
>
> !DSPAM:5ec76256254551748016490!
>
>
+--------------------+--------------------------+-----------------------+
| Paul Goyette | PGP Key fingerprint: | E-mail addresses: |
| (Retired) | FA29 0E3B 35AF E8AE 6651 | <email address hidden> |
| Software Developer | 0786 F758 55DE 53BA 7731 | <email address hidden> |
+--------------------+--------------------------+-----------------------+
[Expired for QEMU because there has been no activity for 60 days.]
|