3 files changed, 14 insertions, 8 deletions

diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c
index 1fb8b239e567..5cc608de6883 100644
--- a/kernel/debug/debug_core.c
+++ b/kernel/debug/debug_core.c
@@ -592,6 +592,8 @@ return_normal:
                                 arch_kgdb_ops.correct_hw_break();
                         if (trace_on)
                                 tracing_on();
+                        kgdb_info[cpu].debuggerinfo = NULL;
+                        kgdb_info[cpu].task = NULL;
                         kgdb_info[cpu].exception_state &=
                                 ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE);
                         kgdb_info[cpu].enter_kgdb--;
@@ -724,6 +726,8 @@ kgdb_restore:
         if (trace_on)
                 tracing_on();
 
+        kgdb_info[cpu].debuggerinfo = NULL;
+        kgdb_info[cpu].task = NULL;
         kgdb_info[cpu].exception_state &=
                 ~(DCPU_WANT_MASTER | DCPU_IS_SLAVE);
         kgdb_info[cpu].enter_kgdb--;
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c
index 7921ae4fca8d..7e2379aa0a1e 100644
--- a/kernel/debug/kdb/kdb_bt.c
+++ b/kernel/debug/kdb/kdb_bt.c
@@ -186,7 +186,16 @@ kdb_bt(int argc, const char **argv)
                 kdb_printf("btc: cpu status: ");
                 kdb_parse("cpu\n");
                 for_each_online_cpu(cpu) {
-                        sprintf(buf, "btt 0x%px\n", KDB_TSK(cpu));
+                        void *kdb_tsk = KDB_TSK(cpu);
+
+                        /* If a CPU failed to round up we could be here */
+                        if (!kdb_tsk) {
+                                kdb_printf("WARNING: no task for cpu %ld\n",
+                                           cpu);
+                                continue;
+                        }
+
+                        sprintf(buf, "btt 0x%px\n", kdb_tsk);
                         kdb_parse(buf);
                         touch_nmi_watchdog();
                 }
diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
index 15e1a7af5dd0..53a0df6e4d92 100644
--- a/kernel/debug/kdb/kdb_debugger.c
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -118,13 +118,6 @@ int kdb_stub(struct kgdb_state *ks)
         kdb_bp_remove();
         KDB_STATE_CLEAR(DOING_SS);
         KDB_STATE_SET(PAGER);
-        /* zero out any offline cpu data */
-        for_each_present_cpu(i) {
-                if (!cpu_online(i)) {
-                        kgdb_info[i].debuggerinfo = NULL;
-                        kgdb_info[i].task = NULL;
-                }
-        }
         if (ks->err_code == DIE_OOPS || reason == KDB_REASON_OOPS) {
                 ks->pass_exception = 1;
                 KDB_FLAG_SET(CATASTROPHIC);