From: John Ogness john.ogness@linutronix.de Subject: fs/proc/array.c: allow reporting eip/esp for all coredumping threads
0a1eb2d474ed ("fs/proc: Stop reporting eip and esp in /proc/PID/stat") stopped reporting eip/esp and fd7d56270b52 ("fs/proc: Report eip/esp in /prod/PID/stat for coredumping") reintroduced the feature to fix a regression with userspace core dump handlers (such as minicoredumper).
Because PF_DUMPCORE is only set for the primary thread, this didn't fix the original problem for secondary threads. Allow reporting the eip/esp for all threads by checking for PF_EXITING as well. This is set for all the other threads when they are killed. coredump_wait() waits for all the tasks to become inactive before proceeding to invoke a core dumper.
Link: http://lkml.kernel.org/r/87y32p7i7a.fsf@linutronix.de Link: http://lkml.kernel.org/r/20190522161614.628-1-jlu@pengutronix.de Fixes: fd7d56270b526ca3 ("fs/proc: Report eip/esp in /prod/PID/stat for coredumping") Signed-off-by: John Ogness john.ogness@linutronix.de Reported-by: Jan Luebbe jlu@pengutronix.de Tested-by: Jan Luebbe jlu@pengutronix.de Cc: Alexey Dobriyan adobriyan@gmail.com Cc: Andy Lutomirski luto@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
fs/proc/array.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/proc/array.c~fs-proc-allow-reporting-eip-esp-for-all-coredumping-threads +++ a/fs/proc/array.c @@ -462,7 +462,7 @@ static int do_task_stat(struct seq_file * a program is not able to use ptrace(2) in that case. It is * safe because the task has stopped executing permanently. */ - if (permitted && (task->flags & PF_DUMPCORE)) { + if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) { if (try_get_task_stack(task)) { eip = KSTK_EIP(task); esp = KSTK_ESP(task); _