[PATCH 2/2] scripts/gdb: Support getting current task struct in UML
Jan Kiszka
jan.kiszka at siemens.com
Tue Feb 14 23:45:20 PST 2023
On 15.02.23 00:35, Glenn Washburn wrote:
> A running x86 UML kernel reports with architecture "i386:x86-64" as
> it is a sub-architecture. However, a difference with bare-metal x86
> kernels is in how it manages tasks and the current task struct. To
> identify that the inferior is a UML kernel and not bare-metal, the
> symbol "uml_kmalloc" is checked for. If it exists, then do the UML
> specific way of getting the current task struct.
>
> Signed-off-by: Glenn Washburn <development at efficientek.com>
> ---
> scripts/gdb/linux/cpus.py | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/scripts/gdb/linux/cpus.py b/scripts/gdb/linux/cpus.py
> index 289f0bf4d2a1..90908653f6c7 100644
> --- a/scripts/gdb/linux/cpus.py
> +++ b/scripts/gdb/linux/cpus.py
> @@ -163,8 +163,12 @@ def get_current_task(cpu):
> task_ptr_type = task_type.get_type().pointer()
>
> if utils.is_target_arch("x86"):
> - var_ptr = gdb.parse_and_eval("¤t_task")
> - return per_cpu(var_ptr, cpu).dereference()
> + if gdb.lookup_global_symbol("uml_kmalloc"):
> + var_ptr = gdb.parse_and_eval("(struct task_struct *)cpu_tasks[0].task")
Can't we use an UML indicator that is related to the topic? Why not
cpu_tasks itself?
> + return var_ptr.dereference()
> + else:
> + var_ptr = gdb.parse_and_eval("¤t_task")
> + return per_cpu(var_ptr, cpu).dereference()
> elif utils.is_target_arch("aarch64"):
> current_task_addr = gdb.parse_and_eval("$SP_EL0")
> if((current_task_addr >> 63) != 0):
Jan
--
Siemens AG, Technology
Competence Center Embedded Linux
More information about the linux-um
mailing list