[RFC,0/2] Dynamically allocate memory to store task's full name

Message

Bhupesh March 14, 2025, 5:27 a.m. UTC

While working with user-space debugging tools which work especially
on linux gaming platforms, I found that the task name is truncated due
to the limitation of TASK_COMM_LEN.

For example, currently running 'ps', the task->comm value of a long
task name is truncated due to the limitation of TASK_COMM_LEN.
    create_very_lon

This leads to the names passed from userland via pthread_setname_np()
being truncated.

Now, during debug tracing, seeing truncated names is not very useful,
especially on gaming platforms where the number of tasks running can
be very hight.

For example for debug applications invoking 'pthread_getname_np()'
to debug task names.

This RFC aims to start a conversation and improve the initial RFC
patchset to avoid such buffer overflows by introducing a new
dynamically allocated pointer to store task's full name, which
shouldn't introduce too much overhead as it is in the non-critical
path.

After this change, the full name of these (otherwise truncated) tasks
will be shown in 'ps'. For example:
    create_very_long_name_user_space_script.sh

Bhupesh (2):
  exec: Dynamically allocate memory to store task's full name
  fs/proc: Pass 'task->full_name' via 'proc_task_name()'

 fs/exec.c             | 21 ++++++++++++++++++---
 fs/proc/array.c       |  2 +-
 include/linux/sched.h |  9 +++++++++
 3 files changed, 28 insertions(+), 4 deletions(-)