I observe the same situation. My host CPU (Intel Xeon CPU E5-2690) supports 1gb pages but qemu keeps it disabled by default. I have to use either '-cpu phenom' or '-cpu host' with KVM.
It makes me wondering what is the default CPU for QEMU? Is it possible to set qemu CPU featureset closer to what host CPU has? -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1248959 Title: pdpe1gb flag is missing in guest running on Intel h/w Status in QEMU: New Bug description: I need to utilize 1G hugepages on my guest system. But this is not possible as long as there is no pdpe1gb support in guest system. The latest source code contains pdpe1gb support for AMD but not for Intel. Are there any obstacles that does not allow to implement it for modern Intel chips? My configuration: Host: ------- uname -a Linux tripel.salab.cic.nsn-rdnet.net 2.6.32-358.14.1.el6.x86_64 #1 SMP Tue Jul 16 23:51:20 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux cat /etc/*-release CentOS release 6.4 (Final) yum list installed | grep qemu gpxe-roms-qemu.noarch 0.9.7-6.9.el6 @base qemu-img.x86_64 2:0.12.1.2-2.355.0.1.el6.centos.5 qemu-kvm.x86_64 2:0.12.1.2-2.355.0.1.el6.centos.5 cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 45 model name : Intel(R) Xeon(R) CPU E5-2680 0 @ 2.70GHz stepping : 7 cpu MHz : 2700.000 cache size : 20480 KB physical id : 0 siblings : 16 core id : 0 cpu cores : 8 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm pcid dca sse4_1 sse4_2 x2apic popcnt tsc_deadline_timer aes xsave avx lahf_lm ida arat epb xsaveopt pln pts dts tpr_shadow vnmi flexpriority ept vpid bogomips : 5387.09 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual /usr/libexec/qemu-kvm -cpu ? Recognized CPUID flags: f_edx: pbe ia64 tm ht ss sse2 sse fxsr mmx acpi ds clflush pn pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de vme fpu f_ecx: hypervisor rdrand f16c avx osxsave xsave aes tsc-deadline popcnt movbe x2apic sse4.2|sse4_2 sse4.1|sse4_1 dca pcid pdcm xtpr cx16 fma cid ssse3 tm2 est smx vmx ds_cpl monitor dtes64 pclmulqdq|pclmuldq pni|sse3 extf_edx: 3dnow 3dnowext lm|i64 rdtscp pdpe1gb fxsr_opt|ffxsr fxsr mmx mmxext nx|xd pse36 pat cmov mca pge mtrr syscall apic cx8 mce pae msr tsc pse de vme fpu extf_ecx: perfctr_nb perfctr_core topoext tbm nodeid_msr tce fma4 lwp wdt skinit xop ibs osvw 3dnowprefetch misalignsse sse4a abm cr8legacy extapic svm cmp_legacy lahf_lm ps ax | grep qemu 7197 ? Sl 0:15 /usr/libexec/qemu-kvm -name vladimir.AS-0 -S -M rhel6.4.0 -cpu SandyBridge,+pdpe1gb,+osxsave,+dca,+pcid,+pdcm,+xtpr,+tm2,+est,+smx,+vmx,+ds_cpl,+monitor,+dtes64,+pbe,+tm,+ht,+ss,+acpi,+ds,+vme -enable-kvm -m 8192 -mem-prealloc -mem-path /var/lib/hugetlbfs/pagesize-1GB/libvirt/qemu -smp 4,sockets=4,cores=1,threads=1 -uuid ec2d3c58-a7f0-fdbd-9de5-b547a5b3130f -nographic -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/vladimir.AS-0.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -netdev tap,fd=28,id=hostnet0 -device e1000,netdev=hostnet0,id=net0,mac=52:54:00:81:5b:df,bus=pci.0,addr=0x3,bootindex=1 -chardev pty,id=charserial0 -device isa-serial,chardev=charserial0,id=serial0 -device pci-assign,host=02:00.0,id=hostdev0,configfd=29,bus=pci.0,addr=0x4 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 Guest: --------- # uname -a Linux AS-0 2.6.34.13-WR4.3.fp_x86_64_standard-00019-g052bb3e #1 SMP Wed May 8 12:21:02 EEST 2013 x86_64 x86_64 x86_64 GNU/Linux # cat /etc/*-release Wind River Linux 4.3 glibc_cgl # cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 42 model name : Intel Xeon E312xx (Sandy Bridge) stepping : 1 cpu MHz : 2693.893 cache size : 4096 KB fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ss syscall nx lm constant_tsc rep_good pni pclmulqdq ssse3 cx16 sse4_1 sse4_2 x2apic popcnt aes xsave avx hypervisor lahf_lm xsaveopt bogomips : 5387.78 clflush size : 64 cache_alignment : 64 address sizes : 46 bits physical, 48 bits virtual To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1248959/+subscriptions