scripts/gdb: fix debugging modules on s390

Currently lx-symbols assumes that module text is always located at
module->core_layout->base, but s390 uses the following layout:

  +------+  <- module->core_layout->base
  | GOT  |
  +------+  <- module->core_layout->base + module->arch->plt_offset
  | PLT  |
  +------+  <- module->core_layout->base + module->arch->plt_offset +
  | TEXT |     module->arch->plt_size
  +------+

Therefore, when trying to debug modules on s390, all the symbol
addresses are skewed by plt_offset + plt_size.

Fix by adding plt_offset + plt_size to module_addr in
load_module_symbols().

Link: http://lkml.kernel.org/r/20191017085917.81791-1-iii@linux.ibm.com
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Ilya Leoshkevich 2019-10-18 20:20:43 -07:00 committed by Linus Torvalds
parent aa5de305c9
commit 585d730d41

View File

@ -15,7 +15,7 @@ import gdb
import os
import re
from linux import modules
from linux import modules, utils
if hasattr(gdb, 'Breakpoint'):
@ -116,6 +116,12 @@ lx-symbols command."""
module_file = self._get_module_file(module_name)
if module_file:
if utils.is_target_arch('s390'):
# Module text is preceded by PLT stubs on s390.
module_arch = module['arch']
plt_offset = int(module_arch['plt_offset'])
plt_size = int(module_arch['plt_size'])
module_addr = hex(int(module_addr, 0) + plt_offset + plt_size)
gdb.write("loading @{addr}: {filename}\n".format(
addr=module_addr, filename=module_file))
cmdline = "add-symbol-file {filename} {addr}{sections}".format(