Hi,

In /proc/PID/stat, there is the kstkesp field which is the stack pointer of
a thread. While the thread is active, this field reads zero. But during a
coredump, it should have a valid value.

However, at the moment, kstkesp is zero even during coredump.

The first commit fixes this problem, and the second commit adds a selftest
to detect if this problem appears again in the future.

Nam Cao (2):
  fs/proc: do_task_stat: Fix ESP not readable during coredump
  selftests: coredump: Add stackdump test

 fs/proc/array.c                               |  36 ++--
 tools/testing/selftests/coredump/Makefile     |   7 +
 tools/testing/selftests/coredump/README.rst   |  50 ++++++
 tools/testing/selftests/coredump/stackdump    |  14 ++
 .../selftests/coredump/stackdump_test.c       | 154 ++++++++++++++++++
 5 files changed, 243 insertions(+), 18 deletions(-)
 create mode 100644 tools/testing/selftests/coredump/Makefile
 create mode 100644 tools/testing/selftests/coredump/README.rst
 create mode 100755 tools/testing/selftests/coredump/stackdump
 create mode 100644 tools/testing/selftests/coredump/stackdump_test.c

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2.39.5