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> Cc: Sourabh Jain <[email protected]> Cc: Hari Bathini <[email protected]> Cc: Mahesh J Salgaonkar <[email protected]> Cc: Naveen N. Rao <[email protected]> Cc: Lianbo Jiang <[email protected]> Cc: HAGIO KAZUHITO(萩尾一仁) <[email protected]> Cc: Tao Liu <[email protected]> Cc: Alexey Makhalov <[email protected]> Signed-off-by: Tao Liu <[email protected]>
adi-g15-ibm · Aug 27, 2024 · 1b620a8 · 1b620a8
1 parent 37399e5
commit 1b620a8
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diff --git a/defs.h b/defs.h
@@ -7933,6 +7933,7 @@ 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
@@ -16171,3 +16171,32 @@ exit 0
  }
 
  /*
+--- gdb-10.2/gdb/stack.c.orig
++++ gdb-10.2/gdb/stack.c
+@@ -1990,6 +1990,10 @@
+ /* Print briefly all stack frames or just the innermost COUNT_EXP
+    frames.  */
+
++#ifdef CRASH_MERGE
++extern "C" int is_kvaddr(ulong);
++#endif
++
+ static void
+ backtrace_command_1 (const frame_print_options &fp_opts,
+ 		     const backtrace_cmd_options &bt_opts,
+@@ -2082,6 +2086,15 @@
+ 	     hand, perhaps the code does or could be fixed to make sure
+ 	     the frame->prev field gets set to NULL in that case).  */
+
++#ifdef CRASH_MERGE
++	  CORE_ADDR pc = 0;
++	  get_frame_pc_if_available (fi, &pc);
++	  if (!is_kvaddr(pc)) {
++	    printf_filtered (_("Backtrace stopped due to non-kernel addr: %lx\n"),pc);
++	    fi = NULL;
++	    break;
++	  }
++#endif
+ 	  print_frame_info (fp_opts, fi, 1, LOCATION, 1, 0);
+ 	  if ((flags & PRINT_LOCALS) != 0)
+ 	    {
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 @@