patches for easier mirroring, to eliminate a special copy, to make www.freebsd.org/security a full copy of security.freebsd.org and be eventually be the same. For now files are just sitting there. The symlinks are missing. Discussed on: www (repository location) Discussed with: simon (so)
141 lines
3.7 KiB
Diff
141 lines
3.7 KiB
Diff
Index: sys/amd64/amd64/fpu.c
|
|
===================================================================
|
|
RCS file: /home/ncvs/src/sys/amd64/amd64/fpu.c,v
|
|
retrieving revision 1.157
|
|
diff -u -I__FBSDID -r1.157 fpu.c
|
|
--- sys/amd64/amd64/fpu.c 11 Mar 2005 22:16:09 -0000 1.157
|
|
+++ sys/amd64/amd64/fpu.c 16 Apr 2006 20:18:07 -0000
|
|
@@ -96,6 +96,8 @@
|
|
|
|
typedef u_char bool_t;
|
|
|
|
+static void fpu_clean_state(void);
|
|
+
|
|
int hw_float = 1;
|
|
SYSCTL_INT(_hw,HW_FLOATINGPT, floatingpoint,
|
|
CTLFLAG_RD, &hw_float, 0,
|
|
@@ -407,6 +409,8 @@
|
|
PCPU_SET(fpcurthread, curthread);
|
|
pcb = PCPU_GET(curpcb);
|
|
|
|
+ fpu_clean_state();
|
|
+
|
|
if ((pcb->pcb_flags & PCB_FPUINITDONE) == 0) {
|
|
/*
|
|
* This is the first time this thread has used the FPU,
|
|
@@ -474,6 +478,7 @@
|
|
|
|
s = intr_disable();
|
|
if (td == PCPU_GET(fpcurthread)) {
|
|
+ fpu_clean_state();
|
|
fxrstor(addr);
|
|
intr_restore(s);
|
|
} else {
|
|
@@ -484,6 +489,37 @@
|
|
}
|
|
|
|
/*
|
|
+ * On AuthenticAMD processors, the fxrstor instruction does not restore
|
|
+ * the x87's stored last instruction pointer, last data pointer, and last
|
|
+ * opcode values, except in the rare case in which the exception summary
|
|
+ * (ES) bit in the x87 status word is set to 1.
|
|
+ *
|
|
+ * In order to avoid leaking this information across processes, we clean
|
|
+ * these values by performing a dummy load before executing fxrstor().
|
|
+ */
|
|
+static double dummy_variable = 0.0;
|
|
+static void
|
|
+fpu_clean_state(void)
|
|
+{
|
|
+ u_short status;
|
|
+
|
|
+ /*
|
|
+ * Clear the ES bit in the x87 status word if it is currently
|
|
+ * set, in order to avoid causing a fault in the upcoming load.
|
|
+ */
|
|
+ fnstsw(&status);
|
|
+ if (status & 0x80)
|
|
+ fnclex();
|
|
+
|
|
+ /*
|
|
+ * Load the dummy variable into the x87 stack. This mangles
|
|
+ * the x87 stack, but we don't care since we're about to call
|
|
+ * fxrstor() anyway.
|
|
+ */
|
|
+ __asm __volatile("ffree %%st(7); fld %0" : : "m" (dummy_variable));
|
|
+}
|
|
+
|
|
+/*
|
|
* This really sucks. We want the acpi version only, but it requires
|
|
* the isa_if.h file in order to get the definitions.
|
|
*/
|
|
Index: sys/i386/isa/npx.c
|
|
===================================================================
|
|
RCS file: /home/ncvs/src/sys/i386/isa/npx.c,v
|
|
retrieving revision 1.164
|
|
diff -u -I__FBSDID -r1.164 npx.c
|
|
--- sys/i386/isa/npx.c 6 Apr 2006 17:17:45 -0000 1.164
|
|
+++ sys/i386/isa/npx.c 16 Apr 2006 20:18:08 -0000
|
|
@@ -142,6 +142,10 @@
|
|
|
|
typedef u_char bool_t;
|
|
|
|
+#ifdef CPU_ENABLE_SSE
|
|
+static void fpu_clean_state(void);
|
|
+#endif
|
|
+
|
|
static void fpusave(union savefpu *);
|
|
static void fpurstor(union savefpu *);
|
|
static int npx_attach(device_t dev);
|
|
@@ -952,15 +956,49 @@
|
|
fnsave(addr);
|
|
}
|
|
|
|
+#ifdef CPU_ENABLE_SSE
|
|
+/*
|
|
+ * On AuthenticAMD processors, the fxrstor instruction does not restore
|
|
+ * the x87's stored last instruction pointer, last data pointer, and last
|
|
+ * opcode values, except in the rare case in which the exception summary
|
|
+ * (ES) bit in the x87 status word is set to 1.
|
|
+ *
|
|
+ * In order to avoid leaking this information across processes, we clean
|
|
+ * these values by performing a dummy load before executing fxrstor().
|
|
+ */
|
|
+static double dummy_variable = 0.0;
|
|
+static void
|
|
+fpu_clean_state(void)
|
|
+{
|
|
+ u_short status;
|
|
+
|
|
+ /*
|
|
+ * Clear the ES bit in the x87 status word if it is currently
|
|
+ * set, in order to avoid causing a fault in the upcoming load.
|
|
+ */
|
|
+ fnstsw(&status);
|
|
+ if (status & 0x80)
|
|
+ fnclex();
|
|
+
|
|
+ /*
|
|
+ * Load the dummy variable into the x87 stack. This mangles
|
|
+ * the x87 stack, but we don't care since we're about to call
|
|
+ * fxrstor() anyway.
|
|
+ */
|
|
+ __asm __volatile("ffree %%st(7); fld %0" : : "m" (dummy_variable));
|
|
+}
|
|
+#endif /* CPU_ENABLE_SSE */
|
|
+
|
|
static void
|
|
fpurstor(addr)
|
|
union savefpu *addr;
|
|
{
|
|
|
|
#ifdef CPU_ENABLE_SSE
|
|
- if (cpu_fxsr)
|
|
+ if (cpu_fxsr) {
|
|
+ fpu_clean_state();
|
|
fxrstor(addr);
|
|
- else
|
|
+ } else
|
|
#endif
|
|
frstor(addr);
|
|
}
|