SIGBUS Signal 7 Issue

Description

Hi,

I have a high traffic server using PHP-FPM (8.1.27). I have noticed that every so often (once every few hours), one of the child processes end with a message such as this:

WARNING: [pool www] child 2210486 exited on signal 7 (SIGBUS - core dumped) after 2215.744554 seconds from start

You can see the core dump below:

(gdb) bt
#0  __memmove_avx_unaligned_erms () at ../sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S:361
#1  0x00005611cdf29556 in memcpy (__len=<optimized out>, __src=<optimized out>, __dest=<optimized out>) at /usr/include/bits/string_fortified.h:34
#2  php_output_handler_append (buf=0x7ffd180c0488, buf=0x7ffd180c0488, handler=0x7f67b5202230) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/output.c:903
#3  php_output_handler_op (context=0x7ffd180c0480, handler=0x7f67b5202230) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/output.c:951
#4  php_output_op (len=28045, str=0xd579836c4a30 <error: Cannot access memory at address 0xd579836c4a30>, op=0) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/output.c:1067
#5  php_output_write (str=str@entry=0x7f67ba622000 "\037\213\b", len=28045) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/output.c:261
#6  0x00005611cdf2f47c in _php_stream_passthru (stream=stream@entry=0x7f67b527a000) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/streams/streams.c:1438
#7  0x00005611cdeb8b60 in zif_readfile (execute_data=<optimized out>, return_value=0x7ffd180c2680) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/ext/standard/file.c:1344
#8  0x00007f679a9a4c64 in phar_readfile () from /usr/lib64/php/modules/phar.so
#9  0x00005611cdfe6eb3 in ZEND_DO_ICALL_SPEC_RETVAL_UNUSED_HANDLER () at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/Zend/zend_vm_execute.h:1235
#10 execute_ex (ex=0x7f67b527b000) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/Zend/zend_vm_execute.h:55812
#11 0x00005611cdfedccc in zend_execute (op_array=0x7f67b5276100, return_value=0x0) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/Zend/zend_vm_execute.h:60188
#12 0x00005611cdf7d235 in zend_execute_scripts (type=type@entry=8, retval=retval@entry=0x0, file_count=file_count@entry=3) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/Zend/zend.c:1857
#13 0x00005611cdf182aa in php_execute_script (primary_file=<optimized out>) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/main/main.c:2551
#14 0x00005611cddca231 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/php-8.1.27-1.el8.remi.x86_64/sapi/fpm/fpm/fpm_main.c:1935

PHP Version

8.1.27

Operating System

AlmaLinux 8.9