[Crash-utility] [PATCH] Fix for "dis" command to correctly display the offset of disassembly code

For gdb-10.2, the disassembly code may start with "=>", which needs to be stripped when calculating the address. Otherwise, parsing the address will fail because the current code always assumes that it starts with the "0x". For example: crash> gdb disassemble 0xffffffffa2317add Dump of assembler code for function native_queued_spin_lock_slowpath: 0xffffffffa2317ab0 <+0>: nopl 0x0(%rax,%rax,1) 0xffffffffa2317ab5 <+5>: push %rbp 0xffffffffa2317ab6 <+6>: mov %rsp,%rbp ... 0xffffffffa2317ad3 <+35>: mov %edx,%eax 0xffffffffa2317ad5 <+37>: lock cmpxchg %ecx,(%rdi) => 0xffffffffa2317ad9 <+41>: cmp %eax,%edx 0xffffffffa2317adb <+43>: jne 0xffffffffa2317ac0 <native_queued_spin_lock_slowpath+16> 0xffffffffa2317add <+45>: pop %rbp 0xffffffffa2317ade <+46>: xchg %ax,%ax ... Without the patch: crash> dis 0xffffffffa2317add -r | tail -5 0xffffffffa2317ad3 <native_queued_spin_lock_slowpath+35>: mov %edx,%eax 0xffffffffa2317ad5 <native_queued_spin_lock_slowpath+37>: lock cmpxchg %ecx,(%rdi) 0xffffffffa2317ad5 <native_queued_spin_lock_slowpath+37>: cmp %eax,%edx ^^^ 0xffffffffa2317adb <native_queued_spin_lock_slowpath+43>: jne 0xffffffffa2317ac0 <native_queued_spin_lock_slowpath+16> 0xffffffffa2317add <native_queued_spin_lock_slowpath+45>: pop %rbp With the patch: crash> dis 0xffffffffa2317add -r | tail -5 0xffffffffa2317ad3 <native_queued_spin_lock_slowpath+35>: mov %edx,%eax 0xffffffffa2317ad5 <native_queued_spin_lock_slowpath+37>: lock cmpxchg %ecx,(%rdi) 0xffffffffa2317ad9 <native_queued_spin_lock_slowpath+41>: cmp %eax,%edx 0xffffffffa2317adb <native_queued_spin_lock_slowpath+43>: jne 0xffffffffa2317ac0 <native_queued_spin_lock_slowpath+16> 0xffffffffa2317add <native_queued_spin_lock_slowpath+45>: pop %rbp Reported-by: Vernon Lovejoy <vlovejoy(a)redhat.com&gt; Signed-off-by: Lianbo Jiang <lijiang(a)redhat.com&gt; --- kernel.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel.c b/kernel.c index a42e6ad7d78c..6e98f5f6f6b1 100644 --- a/kernel.c +++ b/kernel.c @@ -2112,6 +2112,10 @@ cmd_dis(void) rewind(pc->tmpfile); while (fgets(buf2, BUFSIZE, pc->tmpfile)) { + + if (STRNEQ(buf2, "=>")) + shift_string_left(buf2, 2); + strip_beginning_whitespace(buf2); if (do_load_module_filter) -- 2.37.1