svn commit: r191793 - in stable/7/sys: . amd64/amd64 contrib/pf
dev/ath/ath_hal dev/cxgb i386/isa
John Baldwin
jhb at FreeBSD.org
Mon May 4 19:19:14 UTC 2009
Author: jhb
Date: Mon May 4 19:19:13 2009
New Revision: 191793
URL: http://svn.freebsd.org/changeset/base/191793
Log:
MFC: More refinements to the x86 FPU support:
- Rename (fpu|npx)_cleanstate to (fpu|npx)_initialstate to better reflect
their purpose.
- Fix a few nits in the earlier changes to prevent local information leakage
in AMD FPUs.
Modified:
stable/7/sys/ (props changed)
stable/7/sys/amd64/amd64/fpu.c
stable/7/sys/contrib/pf/ (props changed)
stable/7/sys/dev/ath/ath_hal/ (props changed)
stable/7/sys/dev/cxgb/ (props changed)
stable/7/sys/i386/isa/npx.c
Modified: stable/7/sys/amd64/amd64/fpu.c
==============================================================================
--- stable/7/sys/amd64/amd64/fpu.c Mon May 4 19:06:05 2009 (r191792)
+++ stable/7/sys/amd64/amd64/fpu.c Mon May 4 19:19:13 2009 (r191793)
@@ -101,7 +101,7 @@ static void fpu_clean_state(void);
SYSCTL_INT(_hw, HW_FLOATINGPT, floatingpoint, CTLFLAG_RD,
NULL, 1, "Floating point instructions executed in hardware");
-static struct savefpu fpu_cleanstate;
+static struct savefpu fpu_initialstate;
/*
* Initialize the floating point unit. On the boot CPU we generate a
@@ -123,13 +123,13 @@ fpuinit(void)
mxcsr = __INITIAL_MXCSR__;
ldmxcsr(mxcsr);
if (PCPU_GET(cpuid) == 0) {
- fxsave(&fpu_cleanstate);
- if (fpu_cleanstate.sv_env.en_mxcsr_mask)
- cpu_mxcsr_mask = fpu_cleanstate.sv_env.en_mxcsr_mask;
+ fxsave(&fpu_initialstate);
+ if (fpu_initialstate.sv_env.en_mxcsr_mask)
+ cpu_mxcsr_mask = fpu_initialstate.sv_env.en_mxcsr_mask;
else
cpu_mxcsr_mask = 0xFFBF;
- bzero(fpu_cleanstate.sv_fp, sizeof(fpu_cleanstate.sv_fp));
- bzero(fpu_cleanstate.sv_xmm, sizeof(fpu_cleanstate.sv_xmm));
+ bzero(fpu_initialstate.sv_fp, sizeof(fpu_initialstate.sv_fp));
+ bzero(fpu_initialstate.sv_xmm, sizeof(fpu_initialstate.sv_xmm));
}
start_emulating();
intr_restore(savecrit);
@@ -416,10 +416,11 @@ fpudna(void)
if ((pcb->pcb_flags & PCB_FPUINITDONE) == 0) {
/*
- * This is the first time this thread has used the FPU,
- * explicitly load sanitized registers.
+ * This is the first time this thread has used the FPU or
+ * the PCB doesn't contain a clean FPU state. Explicitly
+ * load an initial state.
*/
- fxrstor(&fpu_cleanstate);
+ fxrstor(&fpu_initialstate);
if (pcb->pcb_initial_fpucw != __INITIAL_FPUCW__)
fldcw(&pcb->pcb_initial_fpucw);
pcb->pcb_flags |= PCB_FPUINITDONE;
@@ -453,7 +454,7 @@ fpugetregs(struct thread *td, struct sav
register_t s;
if ((td->td_pcb->pcb_flags & PCB_FPUINITDONE) == 0) {
- bcopy(&fpu_cleanstate, addr, sizeof(fpu_cleanstate));
+ bcopy(&fpu_initialstate, addr, sizeof(fpu_initialstate));
addr->sv_env.en_cw = td->td_pcb->pcb_initial_fpucw;
return (_MC_FPOWNED_NONE);
}
@@ -479,7 +480,6 @@ fpusetregs(struct thread *td, struct sav
s = intr_disable();
if (td == PCPU_GET(fpcurthread)) {
- fpu_clean_state();
fxrstor(addr);
intr_restore(s);
} else {
@@ -498,10 +498,10 @@ fpusetregs(struct thread *td, struct sav
* 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)
{
+ static float dummy_variable = 0.0;
u_short status;
/*
Modified: stable/7/sys/i386/isa/npx.c
==============================================================================
--- stable/7/sys/i386/isa/npx.c Mon May 4 19:06:05 2009 (r191792)
+++ stable/7/sys/i386/isa/npx.c Mon May 4 19:19:13 2009 (r191793)
@@ -172,7 +172,7 @@ SYSCTL_INT(_hw, HW_FLOATINGPT, floatingp
static volatile u_int npx_intrs_while_probing;
static volatile u_int npx_traps_while_probing;
-static union savefpu npx_cleanstate;
+static union savefpu npx_initialstate;
static bool_t npx_ex16;
static bool_t npx_exists;
static bool_t npx_irq13;
@@ -414,24 +414,24 @@ npx_attach(dev)
s = intr_disable();
stop_emulating();
- fpusave(&npx_cleanstate);
+ fpusave(&npx_initialstate);
start_emulating();
#ifdef CPU_ENABLE_SSE
if (cpu_fxsr) {
- if (npx_cleanstate.sv_xmm.sv_env.en_mxcsr_mask)
+ if (npx_initialstate.sv_xmm.sv_env.en_mxcsr_mask)
cpu_mxcsr_mask =
- npx_cleanstate.sv_xmm.sv_env.en_mxcsr_mask;
+ npx_initialstate.sv_xmm.sv_env.en_mxcsr_mask;
else
cpu_mxcsr_mask = 0xFFBF;
- bzero(npx_cleanstate.sv_xmm.sv_fp,
- sizeof(npx_cleanstate.sv_xmm.sv_fp));
- bzero(npx_cleanstate.sv_xmm.sv_xmm,
- sizeof(npx_cleanstate.sv_xmm.sv_xmm));
+ bzero(npx_initialstate.sv_xmm.sv_fp,
+ sizeof(npx_initialstate.sv_xmm.sv_fp));
+ bzero(npx_initialstate.sv_xmm.sv_xmm,
+ sizeof(npx_initialstate.sv_xmm.sv_xmm));
/* XXX might need even more zeroing. */
} else
#endif
- bzero(npx_cleanstate.sv_87.sv_ac,
- sizeof(npx_cleanstate.sv_87.sv_ac));
+ bzero(npx_initialstate.sv_87.sv_ac,
+ sizeof(npx_initialstate.sv_87.sv_ac));
intr_restore(s);
#ifdef I586_CPU_XXX
if (cpu_class == CPUCLASS_586 && npx_ex16 &&
@@ -785,13 +785,18 @@ npxdna(void)
PCPU_SET(fpcurthread, curthread);
pcb = PCPU_GET(curpcb);
+#ifdef CPU_ENABLE_SSE
+ if (cpu_fxsr)
+ fpu_clean_state();
+#endif
+
if ((pcb->pcb_flags & PCB_NPXINITDONE) == 0) {
/*
* This is the first time this thread has used the FPU or
* the PCB doesn't contain a clean FPU state. Explicitly
- * load sanitized registers.
+ * load an initial state.
*/
- fpurstor(&npx_cleanstate);
+ fpurstor(&npx_initialstate);
if (pcb->pcb_initial_npxcw != __INITIAL_NPXCW__)
fldcw(&pcb->pcb_initial_npxcw);
pcb->pcb_flags |= PCB_NPXINITDONE;
@@ -891,7 +896,7 @@ npxgetregs(td, addr)
return (_MC_FPOWNED_NONE);
if ((td->td_pcb->pcb_flags & PCB_NPXINITDONE) == 0) {
- bcopy(&npx_cleanstate, addr, sizeof(npx_cleanstate));
+ bcopy(&npx_initialstate, addr, sizeof(npx_initialstate));
SET_FPU_CW(addr, td->td_pcb->pcb_initial_npxcw);
return (_MC_FPOWNED_NONE);
}
@@ -967,10 +972,10 @@ fpusave(addr)
* 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)
{
+ static float dummy_variable = 0.0;
u_short status;
/*
@@ -996,10 +1001,9 @@ fpurstor(addr)
{
#ifdef CPU_ENABLE_SSE
- if (cpu_fxsr) {
- fpu_clean_state();
+ if (cpu_fxsr)
fxrstor(addr);
- } else
+ else
#endif
frstor(addr);
}
More information about the svn-src-all
mailing list