diff options
| author | grehan <grehan@FreeBSD.org> | 2017-03-25 05:09:03 +0000 |
|---|---|---|
| committer | grehan <grehan@FreeBSD.org> | 2017-03-25 05:09:03 +0000 |
| commit | 8f0fb5d1b92fb55a894bab8f8bdae126d829c1f9 (patch) | |
| tree | a0abe2e0d44e86196b6b191b6ed1b582822d7ac3 | |
| parent | 5f66a0a5cff9df60880fe6cc194f755e2cd96409 (diff) | |
| download | FreeBSD-src-8f0fb5d1b92fb55a894bab8f8bdae126d829c1f9.zip FreeBSD-src-8f0fb5d1b92fb55a894bab8f8bdae126d829c1f9.tar.gz | |
MFC r315361 and r315364: Hide MONITORX/MWAITX from guests.
r315361
Add the AMD MONITORX/MWAITX feature definition introduced in
Bulldozer/Ryzen CPUs.
r315364
Hide the AMD MONITORX/MWAITX capability.
Otherwise, recent Linux guests will use these instructions, resulting
in #UD exceptions since bhyve doesn't implement MONITOR/MWAIT exits.
This fixes boot-time hangs in recent Linux guests on Ryzen CPUs
(and probably Bulldozer aka AMD FX as well).
| -rw-r--r-- | sys/amd64/vmm/x86.c | 3 | ||||
| -rw-r--r-- | sys/x86/include/specialreg.h | 1 | ||||
| -rw-r--r-- | sys/x86/x86/identcpu.c | 2 |
3 files changed, 5 insertions, 1 deletions
diff --git a/sys/amd64/vmm/x86.c b/sys/amd64/vmm/x86.c index 525e1d9..61d99d5 100644 --- a/sys/amd64/vmm/x86.c +++ b/sys/amd64/vmm/x86.c @@ -176,6 +176,9 @@ x86_emulate_cpuid(struct vm *vm, int vcpu_id, /* Don't advertise the OS visible workaround feature */ regs[2] &= ~AMDID2_OSVW; + /* Hide mwaitx/monitorx capability from the guest */ + regs[2] &= ~AMDID2_MWAITX; + /* * Hide rdtscp/ia32_tsc_aux until we know how * to deal with them. diff --git a/sys/x86/include/specialreg.h b/sys/x86/include/specialreg.h index 3e04273..2cfe5b4 100644 --- a/sys/x86/include/specialreg.h +++ b/sys/x86/include/specialreg.h @@ -226,6 +226,7 @@ #define AMDID2_DBE 0x04000000 #define AMDID2_PTSC 0x08000000 #define AMDID2_PTSCEL2I 0x10000000 +#define AMDID2_MWAITX 0x20000000 /* * CPUID instruction 1 eax info diff --git a/sys/x86/x86/identcpu.c b/sys/x86/x86/identcpu.c index fc32c8d..f419254 100644 --- a/sys/x86/x86/identcpu.c +++ b/sys/x86/x86/identcpu.c @@ -875,7 +875,7 @@ printcpuinfo(void) "\033DBE" /* Data Breakpoint extension */ "\034PTSC" /* Performance TSC */ "\035PL2I" /* L2I perf count */ - "\036<b29>" + "\036MWAITX" /* MONITORX/MWAITX instructions */ "\037<b30>" "\040<b31>" ); |
