Apache SIGTERM causes module shutdown to run at runtime

Description

Apache workers tends to sometimes crash when killed via SIGTERM:

Sample trace:

#2 php_module_shutdown () at ./main/main.c:2455
#3 0x00007fee0fbfc83d in php_module_shutdown_wrapper (sapi_globals=<optimized out>) at ./main/main.c:2448
#4 0x00007fee0fce6d05 in php_apache_child_shutdown (tmp=<optimized out>) at ./sapi/apache2handler/sapi_apache2.c:422
#5 0x00007fee11324d2e in apr_pool_destroy () from /usr/lib/x86_64-linux-gnu/libapr-1.so.0
#6 0x00007fee10f83303 in clean_child_exit () from /usr/lib/apache2/modules/mod_mpm_prefork.so
#7 0x00007fee10f83341 in just_die () from /usr/lib/apache2/modules/mod_mpm_prefork.so
#8 0x00007fee0fc866cd in zend_signal_handler (signo=signo@entry=15, siginfo=siginfo@entry=0x7fffe103fc30, context=context@entry=0x7fffe103fb00) at ./Zend/zend_signal.c:217
#9 0x00007fee0fc86873 in zend_signal_handler_defer (signo=15, siginfo=0x7fffe103fc30, context=0x7fffe103fb00) at ./Zend/zend_signal.c:102
#10 <signal handler called>
#11 0x00007fee11203bbf in __GI___poll (fds=fds@entry=0x7fffe1040890, nfds=nfds@entry=1, timeout=86400000) at ../sysdeps/unix/sysv/linux/poll.c:29
<a mysql function here>

The specific crash location within php_module_shutdown can vary quite a bit, depending on when exactly the signal handler was called.
But in particular, PHP does quite a lot of cleanup during module shutdown, and most is neither signal safe, nor can refcounts be relied on being correct.

I'd expect PHP to avoid any complex operations (like a module shutdown) upon receiving a SIGTERM signal. (Just like PHP also avoids doing special handling for CLI processes receiving a SIGTERM.)

PHP Version

PHP 7.4 - 8.4

Operating System

No response

Bắt đầu với php_apache_child_shutdown trong sapi/apache2handler/sapi_apache2.c và đường đi của php_module_shutdown trong main/main.c, sau đó kiểm tra việc xử lý SIGTERM trong Zend/zend_signal.c. So sánh đường đi của Apache worker với hành vi CLI SIGTERM được mô tả trong issue và tái hiện Apache shutdown trace. Hoàn tất khi SIGTERM không còn đi vào unsafe module-shutdown cleanup trong các Apache worker.