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Description of problem: Flag smap should not be enabled not be enabled in rhel6 machine type Version-Release number of selected component (if applicable): qemu-kvm-1.5.3-126.el7.x86_64 How reproducible: 100% Steps to Reproduce: 1.Boot rhel7.3 guest with cli: /usr/libexec/qemu-kvm -name rhel7.3 -m 2048 \ -smp 6,threads=2,cores=1,sockets=3,maxcpus=6 \ -vga qxl\ -spice port=3001,disable-ticketing \ -device virtio-serial -chardev spicevmc,id=vdagent,debug=0,name=vdagent \ -serial unix:/tmp/m,server,nowait \ -device virtserialport,chardev=vdagent,name=com.redhat.spice.0 \ -drive file=/home/skylake.qcow2,if=none,id=drive-scsi-disk0,format=qcow2,cache=none,werror=stop,rerror=stop -device virtio-scsi-pci,id=scsi0 -device scsi-hd,drive=drive-scsi-disk0,bus=scsi0.0,scsi-id=0,lun=0,id=scsi-disk0,bootindex=1 \ -monitor stdio \ -usb -device usb-kbd,id=input0 \ -netdev tap,id=idinWyYp,vhost=on -device virtio-net-pci,mac=42:ce:a9:d2:4d:d7,id=idlbq7eA,netdev=idinWyYp \ -qmp tcp:localhost:4444,server,nowait \ -machine rhel6.6.0\ -cpu Skylake-Client,check,enforce \ 2. Check flags inside guest by cat /proc/cpuinfo 3. Actual results: smap flag can be found Expected results: smap flag cannot be found Additional info: If boot guest with -cpu Broadwell,check,enforce -machine rhel6.6.0, smap flag cannot be found inside guest. guest cpuinfo: # cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 94 model name : Intel Core Processor (Skylake) stepping : 3 microcode : 0x1 cpu MHz : 2903.996 cache size : 4096 KB physical id : 0 siblings : 2 core id : 0 cpu cores : 1 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 mmx fxsr sse sse2 ht syscall nx lm constant_tsc rep_good nopl eagerfpu pni pclmulqdq ssse3 fma cx16 pcid sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand hypervisor lahf_lm abm 3dnowprefetch fsgsbase bmi1 hle avx2 smep bmi2 erms invpcid rtm mpx rdseed adx smap xsaveopt xsavec xgetbv1 bogomips : 5807.99 clflush size : 64 cache_alignment : 64 address sizes : 39 bits physical, 48 bits virtual power management:
The Skylake Client CPU model never existed in RHEL 6.6, so you cannot execute "/usr/libexec/qemu-kvm -m rhel6.6.0 -cpu Skylake-client" on RHEL6.6. So there is no need for compatibility measures to disable SMAP.