search for: vmxe

...I''m a student and recently work on my bachelor thesis. My goal is to write a little hypervisor. I''m not quite sure if this is the right mailing list, but i guess you''ll gonna tell me. i have two quick questions: 1. before i can use the vmxon instruction i do have to set vmxe flag in cr4 register. but what if some hypervisor is already running? is there a way to check if one is running?? 2. before i set the vmxe bit in cr4, i check if it is already enabled. i do this while my module gets loaded. but i observed a strange thing. sometimes the vmxe bit seems to be set wh...

hvm: clear vmxe if vmxoff The current Xen code keeps X86_CR4_VMXE set even if VMXON has not been executed. The stop_vmx() code assumes that it is possible to call VMXOFF if X86_CR4_VMXE is set which is not always true. Calling VMXOFF without VMXON results in an illegal opcode trap, and to avoid this condition t...

...A20M. 2. allocate a 4kb-aligned vmxon region and calculate its physical address. 3. setup identity page table and enter protected page mode. In this step I also set x86_cr0_ne ( cr0.bit5) 4. call start_vmx. This start_vmx function is similar to the one in xen3.1.0 a. test cpuid with eax = 1. ecx.vmxe(bit5) is 1. b. Test IA32_FEATURE_CONTROL_MSR, result is 0x05, so bit 0 and bit 2 are both 1. c. Set cr4.vmxe (bit13) to 1 d. Call vmx_init_vmcs_config(). This function is the same as in xen3.1.0. e. Call vmxon, passing it the physical adderss calculated in step2, using the same op-code as xen...

...terms. panic[cpu0]/thread=fffffffffbc3cba0: BAD TRAP: type=e (#pf Page fault) rp=fffffffffbc6e9c0 addr=fffffe0017a26f68 #pf Page fault Bad kernel fault at addr=0xfffffe0017a26f68 pid=0, pc=0xfffffffffb885d03, sp=0xfffffffffbc6eab8, eflags=0x10046 cr0: 80050033<pg,wp,ne,et,mp,pe> cr4: 2620<vmxe,xmme,fxsr,pae> cr2: fffffe0017a26f68 rdi: fffffe0017a26f68 rsi: 0 rdx: 80000000bafcb673 rcx: 3 r8: 0 r9: ffffff00c5fed000 rax: 0 rbx: 80000000bafcb673 rbp: fffffffffbc6eb50 r10: 0 r11: ff...

This patch series is a reworking of a series developed by Mukesh Rathor at Oracle. The entirety of the design and development was done by him; I have only reworked, reorganized, and simplified things in a way that I think makes more sense. The vast majority of the credit for this effort therefore goes to him. This version is labelled v13 because it is based on his most recent series, v11.