Date: Fri, 14 Apr 2017 16:54:52 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 218662] bhyve exposes CPU feature SDBG to guests, causing guest panic on OpenBSD 6.1 Message-ID: <bug-218662-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D218662 Bug ID: 218662 Summary: bhyve exposes CPU feature SDBG to guests, causing guest panic on OpenBSD 6.1 Product: Base System Version: 10.3-RELEASE Hardware: amd64 OS: Any Status: New Severity: Affects Some People Priority: --- Component: bin Assignee: freebsd-bugs@FreeBSD.org Reporter: todd.mortimer@gmail.com When attempting to create an OpenBSD 6.1 bhyve guest on 10.3-RELEASE-p18, t= he guest panics early in the boot process when attempting to disable the Silic= on Debug feature identified by CPU feature bit SDBG. This feature bit is passe= d to guests if present on the host CPU.=20 In my case, my CPU is this: CPU: Intel(R) Core(TM) i7-4790S CPU @ 3.20GHz (3192.68-MHz K8-class CPU) Origin=3D"GenuineIntel" Id=3D0x306c3 Family=3D0x6 Model=3D0x3c Steppi= ng=3D3 =20 Features=3D0xbfebfbff<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,HTT,TM,PBE> =20 Features2=3D0x7ffafbff<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,SMX,EST,TM2,SSS= E3,SDBG,FMA,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,TSCDLT,AE= SNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND> AMD Features=3D0x2c100800<SYSCALL,NX,Page1GB,RDTSCP,LM> AMD Features2=3D0x21<LAHF,ABM> Structured Extended Features=3D0x27ab<FSGSBASE,TSCADJ,BMI1,AVX2,SMEP,BMI2,ERMS,INVPCID,NFPUSG> XSAVE Features=3D0x1<XSAVEOPT> VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID TSC: P-state invariant, performance statistics When OpenBSD 6.1 boots under byhve, it detects the SDBG feature and attempt= s to disable it, resulting in a protection fault / panic. This was discussed on the OpenBSD misc list: http://marc.info/?l=3Dopenbsd-misc&m=3D149136052120277&w=3D4 And a patch for HardenedBSD is here: https://github.com/HardenedBSD/hardenedBSD/commit/cc91b57f4d1dabddfbf8b1e76= 55 As a workaround, passing -w to byhve allows the guest to boot, but the CPU feature should be masked out by the host. --=20 You are receiving this mail because: You are the assignee for the bug.=
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