Added arm64 related notes to using gdb

1 files changed, 31 insertions, 0 deletions

diff --git a/md/writeup/using_gdb.md b/md/writeup/using_gdb.md
index 3346e41..5a91a48 100644
--- a/md/writeup/using_gdb.md
+++ b/md/writeup/using_gdb.md
@@ -87,6 +87,13 @@ print value in hex
 ```
 
 
+### ARM
+
+print value of memmory using register
+
+```bash
+x/10x $sp
+```
 
 ## Print memory
 
@@ -141,6 +148,30 @@ set print pretty on
 (gdb) next
 ```
 
+## Show source code
+### Show current instruction
+```bash
+=> 0x801a0 <mbox_call+80>:  ldr w1, [x2]
+(gdb) x/i $pc
+```
+
+### Show n number of instructions
+
+```bash
+(gdb) x/10i $pc
+=> 0x801a0 <mbox_call+80>:  ldr w1, [x2]
+   0x801a4 <mbox_call+84>:  tbnz    w1, #30, 0x801a0 <mbox_call+80>
+   0x801a8 <mbox_call+88>:  ldr w1, [x3]
+   0x801ac <mbox_call+92>:  cmp w0, w1
+   0x801b0 <mbox_call+96>:  b.ne    0x801a0 <mbox_call+80>  // b.any
+   0x801b4 <mbox_call+100>: ldp x19, x20, [sp, #16]
+   0x801b8 <mbox_call+104>: ldp x29, x30, [sp], #32
+   0x801bc <mbox_call+108>: ret
+   0x801c0 <pl011_init>:    sub sp, sp, #0x10
+   0x801c4 <pl011_init+4>:  mov w0, #0x3344                 // #13124
+```
+
+
 ### Links
 
 1. [http://althing.cs.dartmouth.edu/secref/resources/plt-got.txt](http://althing.cs.dartmouth.edu/secref/resources/plt-got.txt)