+ scripts-gdb-make-get_thread_info-accept-pointers.patch added to mm-nonmm-unstable branch

+ scripts-gdb-make-get_thread_info-accept-pointers.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: scripts/gdb: make get_thread_info accept pointers
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     scripts-gdb-make-get_thread_info-accept-pointers.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/scripts-gdb-make-get_thread_info-accept-pointers.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Florian Rommel <mail@florommel.de>
Subject: scripts/gdb: make get_thread_info accept pointers
Date: Thu, 25 Apr 2024 17:35:00 +0200

get_thread_info ($lx_thread_info) only accepted a dereferenced task
parameter.  Passing a pointer to a task_struct (like $lx_per_cpu does with
KGDB) threw an exception.

With this patch, both (dereferenced values and pointers) are accepted.

Before (on x86, KGDB):
>>> p $lx_per_cpu(cpu_info)
Traceback (most recent call last):
  File "./scripts/gdb/linux/cpus.py", line 158, in invoke
    return per_cpu(var_ptr, cpu)
           ^^^^^^^^^^^^^^^^^^^^^
  File "./scripts/gdb/linux/cpus.py", line 42, in per_cpu
    cpu = get_current_cpu()
          ^^^^^^^^^^^^^^^^^
  File "./scripts/gdb/linux/cpus.py", line 33, in get_current_cpu
    return tasks.get_thread_info(tasks.get_task_by_pid(tid))['cpu']
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "./scripts/gdb/linux/tasks.py", line 88, in get_thread_info
    if task.type.fields()[0].type == thread_info_type.get_type():
       ~~~~~~~~~~~~~~~~~~^^^
IndexError: list index out of range

Link: https://lkml.kernel.org/r/20240425153501.749966-4-mail@florommel.de
Signed-off-by: Florian Rommel <mail@florommel.de>
Cc: Andrew Jones <ajones@ventanamicro.com>
Cc: Deepak Gupta <debug@rivosinc.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Kieran Bingham <kbingham@kernel.org>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 scripts/gdb/linux/tasks.py |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/scripts/gdb/linux/tasks.py~scripts-gdb-make-get_thread_info-accept-pointers
+++ a/scripts/gdb/linux/tasks.py
@@ -85,7 +85,7 @@ thread_info_type = utils.CachedType("str
 
 def get_thread_info(task):
     thread_info_ptr_type = thread_info_type.get_type().pointer()
-    if task.type.fields()[0].type == thread_info_type.get_type():
+    if task_type.get_type().fields()[0].type == thread_info_type.get_type():
         return task['thread_info']
     thread_info = task['stack'].cast(thread_info_ptr_type)
     return thread_info.dereference()
_

Patches currently in -mm which might be from mail@florommel.de are

scripts-gdb-fix-failing-kgdb-detection-during-probe.patch
scripts-gdb-fix-parameter-handling-in-lx_per_cpu.patch
scripts-gdb-make-get_thread_info-accept-pointers.patch
scripts-gdb-fix-detection-of-current-cpu-in-kgdb.patch