Author: grehan
Date: Sat Mar 25 05:05:12 2017
New Revision: 315927
URL: https://svnweb.freebsd.org/changeset/base/315927
Log:
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).
Modified:
stable/11/sys/amd64/vmm/x86.c
stable/11/sys/x86/include/specialreg.h
stable/11/sys/x86/x86/identcpu.c
Directory Properties:
stable/11/ (props changed)
Modified: stable/11/sys/amd64/vmm/x86.c
==============================================================================
--- stable/11/sys/amd64/vmm/x86.c Sat Mar 25 02:55:13 2017
(r315926)
+++ stable/11/sys/amd64/vmm/x86.c Sat Mar 25 05:05:12 2017
(r315927)
@@ -176,6 +176,9 @@ x86_emulate_cpuid(struct vm *vm, int vcp
/* 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.
Modified: stable/11/sys/x86/include/specialreg.h
==============================================================================
--- stable/11/sys/x86/include/specialreg.h Sat Mar 25 02:55:13 2017
(r315926)
+++ stable/11/sys/x86/include/specialreg.h Sat Mar 25 05:05:12 2017
(r315927)
@@ -227,6 +227,7 @@
#define AMDID2_DBE 0x04000000
#define AMDID2_PTSC 0x08000000
#define AMDID2_PTSCEL2I 0x10000000
+#define AMDID2_MWAITX 0x20000000
/*
* CPUID instruction 1 eax info
Modified: stable/11/sys/x86/x86/identcpu.c
==============================================================================
--- stable/11/sys/x86/x86/identcpu.c Sat Mar 25 02:55:13 2017
(r315926)
+++ stable/11/sys/x86/x86/identcpu.c Sat Mar 25 05:05:12 2017
(r315927)
@@ -906,7 +906,7 @@ printcpuinfo(void)
"\033DBE" /* Data Breakpoint extension */
"\034PTSC" /* Performance TSC */
"\035PL2I" /* L2I perf count */
- "\036<b29>"
+ "\036MWAITX" /* MONITORX/MWAITX instructions
*/
"\037<b30>"
"\040<b31>"
);
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
