6 Jun
2023
6 Jun
'23
7:13 p.m.
Issue #19716 has been reported by alexdowad (Alex Dowad).
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Bug #19716: SystemStackError occurs too easily on Alpine Linux (due to small stack size
reported by pthread_attr_getstacksize on musl libc)
https://bugs.ruby-lang.org/issues/19716
* Author: alexdowad (Alex Dowad)
* Status: Open
* Priority: Normal
* ruby -v: ruby 3.1.4p223 (2023-03-30 revision 957bb7cb81) [x86_64-linux-musl]
* Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN
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This is the same problem previously reported against Ruby 2.5 in
https://bugs.ruby-lang.org/issues/14387. I just ran into the same problem on Ruby 3.1.4,
built on Alpine Linux 3.16.
@hsbt stated in the previous thread (https://bugs.ruby-lang.org/issues/14387#note-28):
If you have this issue with Ruby 3.2, please file it
with another issue.
I hacked `stack_check` in gc.c to print the values of `STACK_START` and `STACK_END` on
stack overflow; on the Alpine 3.16 host where this problem just occurred, the values
printed were:
Start=0x7ffd0bf4f000, End=0x7ffd0bf32530
...which shows that Ruby thinks the stack size is only 131072 bytes. On the other hand,
`ulimit -s` shows a stack size limit of 8192kb.
This Ruby 3.1.4 was built from unmodified source code downloaded from
https://cache.ruby-lang.org; the build was configured using
`CFLAGS='-march=native' ./configure --disable-install-doc`.
The invocation of Ruby which blew the stack was `bundle exec rake db:migrate`, on a
mid-sized Rails project.
Regarding @ncopa's patch from #14387, @wanabe listed some things which should be done
before it is merged into mainline Ruby:
Okay, The patch needs one or more proofs of its
behaviour, like that:
Original issue [ruby-dev:50421] has gone away.
Standard test codes run well.
test-all
ruby/spec
getrlimit works on some situations like:
on single thread
with multiple threads
with RLIMIT_STACK environment variable
getrlimit code of musl is implemented correctly as expected.
(But It's doubtful whether it can be. I guess that a proof of code soundness is very
difficult.)
Some "real world" applications can work.
I think it is better example that that application(s) can't work without the patch.
I am happy to help cover some of these points if the Ruby development team is still
interested in merging @ncopa's patch.
--
https://bugs.ruby-lang.org/