Stop stack unwinding at non-kernel address

The stack unwinding is for kernel addresses only. If non-kernel address encountered, it is usually a user space address, or non-address value like a function call parameter. So stopping stack unwinding at non-kernel address will decrease the invalid unwind results. Before: crash> gdb bt #0 0xffffffff816a8f65 in context_switch ... crash-utility#1 __schedule () ... crash-utility#2 0xffffffff816a94e9 in schedule ... crash-utility#3 0xffffffff816a86fd in schedule_hrtimeout_range_clock ... crash-utility#4 0xffffffff816a8733 in schedule_hrtimeout_range ... crash-utility#5 0xffffffff8124bb7e in ep_poll ... crash-utility#6 0xffffffff8124d00d in SYSC_epoll_wait ... crash-utility#7 SyS_epoll_wait ... crash-utility#8 <signal handler called> crash-utility#9 0x00007f0449407923 in ?? () crash-utility#10 0xffff880100000001 in ?? () crash-utility#11 0xffff880169b3c010 in ?? () crash-utility#12 0x0000000000000040 in irq_stack_union () crash-utility#13 0xffff880169b3c058 in ?? () crash-utility#14 0xffff880169b3c048 in ?? () crash-utility#15 0xffff880169b3c050 in ?? () crash-utility#16 0x0000000000000000 in ?? () After: crash> gdb bt #0 0xffffffff816a8f65 in context_switch ... crash-utility#1 __schedule () ... crash-utility#2 0xffffffff816a94e9 in schedule () ... crash-utility#3 0xffffffff816a86fd in schedule_hrtimeout_range_clock ... crash-utility#4 0xffffffff816a8733 in schedule_hrtimeout_range ... crash-utility#5 0xffffffff8124bb7e in ep_poll ... crash-utility#6 0xffffffff8124d00d in SYSC_epoll_wait ... crash-utility#7 SyS_epoll_wait ... crash-utility#8 <signal handler called> crash-utility#9 0x00007f0449407923 in ?? () Signed-off-by: Tao Liu <ltao(a)redhat.com>
adi-g15-ibm · Mar 10, 2024 · d0bf224 · d0bf224
1 parent 8a176ee
commit d0bf224
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Showing 3 changed files with 34 additions and 1 deletion.
diff --git a/defs.h b/defs.h
@@ -7920,6 +7920,7 @@ extern unsigned char *gdb_prettyprint_arrays;
 extern unsigned int *gdb_repeat_count_threshold;
 extern unsigned char *gdb_stop_print_at_null;
 extern unsigned int *gdb_output_radix;
+int is_kvaddr(ulong);
 
 /*
  *  gdb/top.c

diff --git a/gdb-10.2.patch b/gdb-10.2.patch
@@ -16110,4 +16110,30 @@ exit 0
 +            (dynamic_cast<stdio_file *>gdb_stderr)->set_stream(original_stderr_stream);
  }
 
- /*
+ /*
+--- gdb-10.2/gdb/frame.c.orig
++++ gdb-10.2/gdb/frame.c
+@@ -2331,6 +2331,10 @@ inside_entry_func (frame_info *this_frame)
+    This function should not contain target-dependent tests, such as
+    checking whether the program-counter is zero.  */
+
++#ifdef CRASH_MERGE
++extern "C" int is_kvaddr(ulong);
++#endif
++
+ struct frame_info *
+ get_prev_frame (struct frame_info *this_frame)
+ {
+@@ -2353,7 +2357,11 @@ get_prev_frame (struct frame_info *this_frame)
+     get_frame_id (this_frame);
+
+   frame_pc_p = get_frame_pc_if_available (this_frame, &frame_pc);
+-
++#ifdef CRASH_MERGE
++  if (!is_kvaddr(frame_pc)) {
++        return NULL;
++  }
++#endif
+   /* tausq/2004-12-07: Dummy frames are skipped because it doesn't make much
+      sense to stop unwinding at a dummy frame.  One place where a dummy
+      frame may have an address "inside_main_func" is on HPUX.  On HPUX, the
diff --git a/gdb_interface.c b/gdb_interface.c
@@ -947,6 +947,12 @@ gdb_lookup_module_symbol(ulong addr, ulong *offset)
 	}
 }
 
+int
+is_kvaddr(ulong addr)
+{
+	return IS_KVADDR(addr);
+}
+
 /*
  *  Used by gdb_interface() to catch gdb-related errors, if desired.
  */
-Original file line number
+Diff line change
@@ Expand Up / @@ -947,6 +947,12 @@ gdb_lookup_module_symbol(ulong addr, ulong *offset) @@
     	}
     }
+    int
+    is_kvaddr(ulong addr)
+    {
+    	return IS_KVADDR(addr);
+    }
     /*
      *  Used by gdb_interface() to catch gdb-related errors, if desired.
      */
@@ Expand Down @@