1 files changed, 35 insertions, 75 deletions

diff --git a/arch/sparc64/kernel/process.c b/arch/sparc64/kernel/process.c
index 8a9cd3e165b9..7f5debdc5fed 100644
--- a/arch/sparc64/kernel/process.c
+++ b/arch/sparc64/kernel/process.c
@@ -52,8 +52,6 @@
 #include <asm/irq_regs.h>
 #include <asm/smp.h>
 
-/* #define VERBOSE_SHOWREGS */
-
 static void sparc64_yield(int cpu)
 {
         if (tlb_type != hypervisor)
@@ -213,22 +211,8 @@ static void show_regwindow(struct pt_regs *regs)
                 printk("I7: <%pS>\n", (void *) rwk->ins[7]);
 }
 
-#ifdef CONFIG_SMP
-static DEFINE_SPINLOCK(regdump_lock);
-#endif
-
-void __show_regs(struct pt_regs * regs)
+void show_regs(struct pt_regs *regs)
 {
-#ifdef CONFIG_SMP
-        unsigned long flags;
-
-        /* Protect against xcall ipis which might lead to livelock on the lock */
-        __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
-                             "wrpr      %0, %1, %%pstate"
-                             : "=r" (flags)
-                             : "i" (PSTATE_IE));
-        spin_lock(&regdump_lock);
-#endif
         printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
                regs->tpc, regs->tnpc, regs->y, print_tainted());
         printk("TPC: <%pS>\n", (void *) regs->tpc);
@@ -246,64 +230,24 @@ void __show_regs(struct pt_regs * regs)
                regs->u_regs[15]);
         printk("RPC: <%pS>\n", (void *) regs->u_regs[15]);
         show_regwindow(regs);
-#ifdef CONFIG_SMP
-        spin_unlock(&regdump_lock);
-        __asm__ __volatile__("wrpr      %0, 0, %%pstate"
-                             : : "r" (flags));
-#endif
 }
 
-#ifdef VERBOSE_SHOWREGS
-static void idump_from_user (unsigned int *pc)
-{
-        int i;
-        int code;
-        
-        if((((unsigned long) pc) & 3))
-                return;
-        
-        pc -= 3;
-        for(i = -3; i < 6; i++) {
-                get_user(code, pc);
-                printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
-                pc++;
-        }
-        printk("\n");
-}
-#endif
+struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
+static DEFINE_SPINLOCK(global_reg_snapshot_lock);
 
-void show_regs(struct pt_regs *regs)
+static bool kstack_valid(struct thread_info *tp, struct reg_window *rw)
 {
-#ifdef VERBOSE_SHOWREGS
-        extern long etrap, etraptl1;
-#endif
-        __show_regs(regs);
-#if 0
-#ifdef CONFIG_SMP
-        {
-                extern void smp_report_regs(void);
+        unsigned long thread_base, fp;
 
-                smp_report_regs();
-        }
-#endif
-#endif
+        thread_base = (unsigned long) tp;
+        fp = (unsigned long) rw;
 
-#ifdef VERBOSE_SHOWREGS 
-        if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
-            regs->u_regs[14] >= (long)current - PAGE_SIZE &&
-            regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
-                printk ("*********parent**********\n");
-                __show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
-                idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
-                printk ("*********endpar**********\n");
-        }
-#endif
+        if (fp < (thread_base + sizeof(struct thread_info)) ||
+            fp >= (thread_base + THREAD_SIZE))
+                return false;
+        return true;
 }
 
-#ifdef CONFIG_MAGIC_SYSRQ
-struct global_reg_snapshot global_reg_snapshot[NR_CPUS];
-static DEFINE_SPINLOCK(global_reg_snapshot_lock);
-
 static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
                               int this_cpu)
 {
@@ -315,14 +259,22 @@ static void __global_reg_self(struct thread_info *tp, struct pt_regs *regs,
         global_reg_snapshot[this_cpu].o7 = regs->u_regs[UREG_I7];
 
         if (regs->tstate & TSTATE_PRIV) {
+                struct thread_info *tp = current_thread_info();
                 struct reg_window *rw;
 
                 rw = (struct reg_window *)
                         (regs->u_regs[UREG_FP] + STACK_BIAS);
-                global_reg_snapshot[this_cpu].i7 = rw->ins[6];
-        } else
+                if (kstack_valid(tp, rw)) {
+                        global_reg_snapshot[this_cpu].i7 = rw->ins[7];
+                        rw = (struct reg_window *)
+                                (rw->ins[6] + STACK_BIAS);
+                        if (kstack_valid(tp, rw))
+                                global_reg_snapshot[this_cpu].rpc = rw->ins[7];
+                }
+        } else {
                 global_reg_snapshot[this_cpu].i7 = 0;
-
+                global_reg_snapshot[this_cpu].rpc = 0;
+        }
         global_reg_snapshot[this_cpu].thread = tp;
 }
 
@@ -341,7 +293,7 @@ static void __global_reg_poll(struct global_reg_snapshot *gp)
         }
 }
 
-static void sysrq_handle_globreg(int key, struct tty_struct *tty)
+void __trigger_all_cpu_backtrace(void)
 {
         struct thread_info *tp = current_thread_info();
         struct pt_regs *regs = get_irq_regs();
@@ -375,13 +327,14 @@ static void sysrq_handle_globreg(int key, struct tty_struct *tty)
                        ((tp && tp->task) ? tp->task->pid : -1));
 
                 if (gp->tstate & TSTATE_PRIV) {
-                        printk("             TPC[%pS] O7[%pS] I7[%pS]\n",
+                        printk("             TPC[%pS] O7[%pS] I7[%pS] RPC[%pS]\n",
                                (void *) gp->tpc,
                                (void *) gp->o7,
-                               (void *) gp->i7);
+                               (void *) gp->i7,
+                               (void *) gp->rpc);
                 } else {
-                        printk("             TPC[%lx] O7[%lx] I7[%lx]\n",
-                               gp->tpc, gp->o7, gp->i7);
+                        printk("             TPC[%lx] O7[%lx] I7[%lx] RPC[%lx]\n",
+                               gp->tpc, gp->o7, gp->i7, gp->rpc);
                 }
         }
 
@@ -390,6 +343,13 @@ static void sysrq_handle_globreg(int key, struct tty_struct *tty)
         spin_unlock_irqrestore(&global_reg_snapshot_lock, flags);
 }
 
+#ifdef CONFIG_MAGIC_SYSRQ
+
+static void sysrq_handle_globreg(int key, struct tty_struct *tty)
+{
+        __trigger_all_cpu_backtrace();
+}
+
 static struct sysrq_key_op sparc_globalreg_op = {
         .handler        = sysrq_handle_globreg,
         .help_msg       = "Globalregs",