From fe8b8bf778689d7b155e3e39af5cb09bf4edcb49 Mon Sep 17 00:00:00 2001
From: Peter Wemm <peter@FreeBSD.org>
Date: Thu, 14 Apr 2005 16:57:58 +0000
Subject: [PATCH] Implement 32-bit compatable fsbase/gsbase methods so that we
 can run (newer) unmodified static i386 binaries again.

---
 sys/amd64/amd64/sys_machdep.c | 21 +++++++++++++++++++++
 sys/amd64/include/sysarch.h   |  5 +++++
 2 files changed, 26 insertions(+)

diff --git a/sys/amd64/amd64/sys_machdep.c b/sys/amd64/amd64/sys_machdep.c
index fcc657a033f..25fbb6f0d04 100644
--- a/sys/amd64/amd64/sys_machdep.c
+++ b/sys/amd64/amd64/sys_machdep.c
@@ -56,8 +56,29 @@ sysarch(td, uap)
 {
 	int error = 0;
 	struct pcb *pcb = curthread->td_pcb;
+	uint32_t i386base;
 
 	switch(uap->op) {
+	case I386_GET_FSBASE:
+		i386base = pcb->pcb_fsbase;
+		error = copyout(&i386base, uap->parms, sizeof(i386base));
+		break;
+	case I386_SET_FSBASE:
+		error = copyin(uap->parms, &i386base, sizeof(i386base));
+		pcb->pcb_fsbase = i386base;
+		if (!error)
+			wrmsr(MSR_FSBASE, pcb->pcb_fsbase);
+		break;
+	case I386_GET_GSBASE:
+		i386base = pcb->pcb_gsbase;
+		error = copyout(&i386base, uap->parms, sizeof(i386base));
+		break;
+	case I386_SET_GSBASE:
+		error = copyin(uap->parms, &i386base, sizeof(i386base));
+		pcb->pcb_gsbase = i386base;
+		if (!error)
+			wrmsr(MSR_KGSBASE, pcb->pcb_gsbase);
+		break;
 	case AMD64_GET_FSBASE:
 		error = copyout(&pcb->pcb_fsbase, uap->parms, sizeof(pcb->pcb_fsbase));
 		break;
diff --git a/sys/amd64/include/sysarch.h b/sys/amd64/include/sysarch.h
index 6918a0a11f5..67c8a4ae99b 100644
--- a/sys/amd64/include/sysarch.h
+++ b/sys/amd64/include/sysarch.h
@@ -35,6 +35,11 @@
 #ifndef _MACHINE_SYSARCH_H_
 #define _MACHINE_SYSARCH_H_
 
+#define	I386_GET_FSBASE		7
+#define	I386_SET_FSBASE		8
+#define	I386_GET_GSBASE		9
+#define	I386_SET_GSBASE		10
+
 /* Leave space for 0-127 for to avoid translating syscalls */
 #define	AMD64_GET_FSBASE	128
 #define	AMD64_SET_FSBASE	129