1 files changed, 34 insertions, 24 deletions

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index bf33c22e38a4..e435bc089ea3 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -44,9 +44,7 @@
 #include <asm/machdep.h>
 #include <asm/rtas.h>
 #include <asm/pmc.h>
-#ifdef CONFIG_PPC32
 #include <asm/reg.h>
-#endif
 #ifdef CONFIG_PMAC_BACKLIGHT
 #include <asm/backlight.h>
 #endif
@@ -1296,43 +1294,54 @@ void vsx_unavailable_exception(struct pt_regs *regs)
         die("Unrecoverable VSX Unavailable Exception", regs, SIGABRT);
 }
 
+#ifdef CONFIG_PPC64
 void facility_unavailable_exception(struct pt_regs *regs)
 {
         static char *facility_strings[] = {
-                "FPU",
-                "VMX/VSX",
-                "DSCR",
-                "PMU SPRs",
-                "BHRB",
-                "TM",
-                "AT",
-                "EBB",
-                "TAR",
+                [FSCR_FP_LG] = "FPU",
+                [FSCR_VECVSX_LG] = "VMX/VSX",
+                [FSCR_DSCR_LG] = "DSCR",
+                [FSCR_PM_LG] = "PMU SPRs",
+                [FSCR_BHRB_LG] = "BHRB",
+                [FSCR_TM_LG] = "TM",
+                [FSCR_EBB_LG] = "EBB",
+                [FSCR_TAR_LG] = "TAR",
         };
-        char *facility, *prefix;
+        char *facility = "unknown";
         u64 value;
+        u8 status;
+        bool hv;
 
-        if (regs->trap == 0xf60) {
-                value = mfspr(SPRN_FSCR);
-                prefix = "";
-        } else {
+        hv = (regs->trap == 0xf80);
+        if (hv)
                 value = mfspr(SPRN_HFSCR);
-                prefix = "Hypervisor ";
+        else
+                value = mfspr(SPRN_FSCR);
+
+        status = value >> 56;
+        if (status == FSCR_DSCR_LG) {
+                /* User is acessing the DSCR.  Set the inherit bit and allow
+                 * the user to set it directly in future by setting via the
+                 * H/FSCR DSCR bit.
+                 */
+                current->thread.dscr_inherit = 1;
+                if (hv)
+                        mtspr(SPRN_HFSCR, value | HFSCR_DSCR);
+                else
+                        mtspr(SPRN_FSCR,  value | FSCR_DSCR);
+                return;
         }
 
-        value = value >> 56;
+        if ((status < ARRAY_SIZE(facility_strings)) &&
+            facility_strings[status])
+                facility = facility_strings[status];
 
         /* We restore the interrupt state now */
         if (!arch_irq_disabled_regs(regs))
                 local_irq_enable();
 
-        if (value < ARRAY_SIZE(facility_strings))
-                facility = facility_strings[value];
-        else
-                facility = "unknown";
-
         pr_err("%sFacility '%s' unavailable, exception at 0x%lx, MSR=%lx\n",
-                prefix, facility, regs->nip, regs->msr);
+               hv ? "Hypervisor " : "", facility, regs->nip, regs->msr);
 
         if (user_mode(regs)) {
                 _exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
@@ -1341,6 +1350,7 @@ void facility_unavailable_exception(struct pt_regs *regs)
 
         die("Unexpected facility unavailable exception", regs, SIGABRT);
 }
+#endif
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM