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 | p...@whooppee.com | | Software Developer | 0786 F758 55DE 53BA 7731 | pgoye...@netbsd.org | +--------------------+--------------------------+-----------------------+ -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. 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
