Speculative fix for MySQL crashes #1135
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https://crash.limetech.org/stats/dbi.mysql.ext.%25/my_real_read https://crash.limetech.org/stats/dbi.mysql.ext.%25/net_real_write Both of these are caused by the VIO ptr ending up as null in the middle of reading/writing to a connection - I can't find any indication of a fix for this made to MySQL, so don't think it is a bug fix we're missing, but there are some musings around the internet that it could be caused by improper thread-safety initialisation. `my_init` (what we had here) is called internally by `mysql_library_init` but I think would have still led to an automatic `mysql_library_init` call the first time `mysql_init` was called (which we can do on a thread in case of threaded connections), which is exactly the thread-safety issue called out by the MySQL docs, so hopefully doing things properly here will help.
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Woah, we didn't have init check prior 😮 |
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I always thought we had mysql_library_init, as it was one of the first things in 23.7.3.2 for writing threaded clients. TIL. |
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https://crash.limetech.org/stats/dbi.mysql.ext.%25/my_real_read https://crash.limetech.org/stats/dbi.mysql.ext.%25/net_real_write Both of these are caused by the VIO ptr ending up as null in the middle of reading/writing to a connection - I can't find any indication of a fix for this made to MySQL, so don't think it is a bug fix we're missing, but there are some musings around the internet that it could be caused by improper thread-safety initialisation. `my_init` (what we had here) is called internally by `mysql_library_init` but I think would have still led to an automatic `mysql_library_init` call the first time `mysql_init` was called (which we can do on a thread in case of threaded connections), which is exactly the thread-safety issue called out by the MySQL docs, so hopefully doing things properly here will help.
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https://crash.limetech.org/stats/dbi.mysql.ext.%25/my_real_read
https://crash.limetech.org/stats/dbi.mysql.ext.%25/net_real_write
Both of these are caused by the VIO ptr ending up as null in the middle of reading/writing to a connection - I can't find any indication of a fix for this made to MySQL, so don't think it is a bug fix we're missing, but there are some musings around the internet that it could be caused by improper thread-safety initialisation.
my_init(what we had here) is called internally bymysql_library_initbut I think would have still led to an automaticmysql_library_initcall the first timemysql_initwas called (which we can do on a thread in case of threaded connections), which is exactly the thread-safety issue called out by the MySQL docs, so hopefully doing things properly here will help.