- ruby-core - ml.ruby-lang.org

[ruby-core:111789] [Ruby master Feature#19333] Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks.
by ioquatix (Samuel Williams) 13 Sep '26

13 Sep '26

Issue #19333 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #19333: Setting (Fiber Local|Thread Local|Fiber Storage) to nil should delete value in order to avoid memory leaks. https://bugs.ruby-lang.org/issues/19333 * Author: ioquatix (Samuel Williams) * Status: Open * Priority: Normal ---------------------------------------- As it stands, Fiber Locals, Thread Locals and Fiber Storage have no way of deleting key-value associations. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 end ``` Because of this, dynamically generated associations can leak over time. This is worse for things like Threads that might be pooled (or maybe an argument against user-space pooling). In any case, having a way to delete those associations would allow application code to at least delete the associations when they no longer make sense. I propose that assigning `nil` to "locals" or "storage" should effectively delete them. e.g. ```ruby 100.times do |i| name = :"variable-#{i}" Thread.current[name] = 10 Thread.current[name] = nil # delete association end ``` A more invasive alternative would be to define new interfaces like `Thread::Local`, `Fiber::Local` and `Fiber::Storage::Local` (or something) which correctly clean up on GC. -- https://bugs.ruby-lang.org/

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[ruby-core:123306] [Ruby Bug#21612] Make sure we never context switch while holding the VM lock
by luke-gru (Luke Gruber) 13 Sep '26

13 Sep '26

Issue #21612 has been reported by luke-gru (Luke Gruber). ---------------------------------------- Bug #21612: Make sure we never context switch while holding the VM lock https://bugs.ruby-lang.org/issues/21612 * Author: luke-gru (Luke Gruber) * Status: Open * Target version: 3.5 * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- ## The Problem We're seeing errors in our application that uses ractors. The errors look like: ``` [BUG] unexpected situation - recordd:1 current:0 error.c:1097 rb_bug_without_die_internal vm_sync.c:275 disallow_reentry eval_intern.h:136 rb_ec_vm_lock_rec_check eval_intern.h:147 rb_ec_tag_state vm.c:2619 rb_vm_exec vm.c:1702 rb_yield eval.c:1173 rb_ensure ``` We concluded that there was context switching going on while a thread held the VM lock. During the investigation into the issue, we added assertions in the code that we never yield to another thread with the VM lock held. We enabled these VM lock assertions even in single ractor mode. These assertions were failing in a few places, but most notably in finalizers. Finalizers are running with the VM lock held, and they were context switching and causing this issue. ## Why Is This Bad? There are a few reasons we shouldn't be able to context switch while holding the VM lock. In single-ractor mode with threads A and B: 1) Anything in this critical section should be thought of as a transaction related to the memory that's changed inside. if A has the lock, manipulates some global memory and yields to B with the lock still taken and without finishing the memory updates and then B takes it and starts writing to the same memory, the state of this global memory could be corrupted. Currently we don't actually take the VM lock in single-ractor mode, but that doesn't mean these issues can't happen. Yielding to another thread in the middle of manipulating global memory *can* still happen and it causes similar issues. In multi-ractor mode with ractors A and B: 1) We get the same issues as in single-ractor mode. 2) We can also get deadlocks if A has the lock, yields to B and B is blocked waiting on the lock. Unfortunately, many things can cause context switching in Ruby, so what is safe to call when the VM lock is taken? ## Guidelines I've come up with some guidelines. With the VM lock held, You should be able to: * Create ruby objects, call `ruby_xmalloc`, etc. * Jump using `EC_JUMP_TAG`. The lock will automatically be unlocked depending on how far up the call stack you locked it and where you're jumping to. * Check ruby interrupts. Since jumping can pop ruby frames and popping frames checks interrupts, you are allowed. It should never context switch with the VM lock held, even if the ruby thread's quantum is up. You shouldn't be able to: * Call any ruby method or enter Ruby's VM loop. For example, `rb_funcall` is not allowed, nor is `rb_warn` (it can call ruby code). `rb_sprintf` is not allowed because it can call `rb_inspect`. * Call `rb_nogvl` * Enter any blocking operation managed by Ruby. * Call a ruby-level mechanism that can context switch, like `rb_mutex_lock`. ## The Fix Of course, unlocking during finalizers is the main fix but there are other places that also need unlocking. I think adding assertions that the VM lock is not held will be important in finding these bugs and not creating regressions in the future. We don't have to add lots of these, just in a few places. These assertions, which only run in debug mode, should also run when in single-ractor mode. ## Future Work I think some documentation would be helpful for what is and isn't allowed while holding the VM lock and other locks in the cruby source. I am currently working on a `Concurrency Guide` for cruby developers that includes this info. It will not go over every lock, just the VM lock and the "all other locks" category. -- https://bugs.ruby-lang.org/

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[ruby-core:116041] [Ruby master Bug#20155] Using value of rb_fiber_scheduler_current() crashes Ruby
by paddor (Patrik Wenger) 13 Sep '26

13 Sep '26

Issue #20155 has been reported by paddor (Patrik Wenger). ---------------------------------------- Bug #20155: Using value of rb_fiber_scheduler_current() crashes Ruby https://bugs.ruby-lang.org/issues/20155 * Author: paddor (Patrik Wenger) * Status: Open * Priority: Normal * ruby -v: ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [x86_64-linux] * Backport: 3.0: UNKNOWN, 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN ---------------------------------------- While trying to manually block/unblock fibers from an extension using the Fiber Scheduler, I noticed that using the return value of `rb_fiber_scheduler_current()` crashes Ruby. I've created a minimal extension gem called "fiber_blocker". Its test suite shows the behavior. See https://github.com/paddor/fiber_blocker, especially the lines containing `FIXME`. Passing `Fiber.scheduler` to the extension functions works. But letting it get the current scheduler itself does not seem to work. Is `rb_fiber_scheduler_current()` not the equivalent to `Fiber.scheduler`? Even just printing the its return value with `#p` will crash Ruby. Ruby either crashes like this: ``` # Running: T1 BEGIN T2 BEGIN T1 END ..T1 BEGIN ext: blocking fiber passed scheduler = #<Scheduler:0x00007fc5f22d39e8 @readable={}, @writable={}, @waiting={}, @closed=false, @lock=#<Thread::Mutex:0x00007fc5f22ec8d0>, @blocking={}, @ready=[], @urgent=[#<IO:fd 5>, #<IO:fd 6>]> T2 BEGIN ext: unblocking fiber T1 END .E Finished in 1.007014s, 3.9721 runs/s, 2.9791 assertions/s. 1) Error: TestFiberBlocker#test_fiber_blocker_current_fiber: fatal: machine stack overflow in critical region No backtrace ``` Or with a segfault: ``` # Running: FiberBlocker.test works. .T1 BEGIN T2 BEGIN T1 END .T1 BEGIN ext: blocking fiber /home/user/dev/oss/async_ruby_test/rbnng/fiber_blocker/test/test_fiber_blocker.rb:40: [BUG] Segmentation fault at 0x00000000390d8f98 ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [x86_64-linux] -- Control frame information ----------------------------------------------- c:0003 p:---- s:0012 e:000011 CFUNC :block_fiber c:0002 p:0014 s:0006 e:000005 BLOCK /home/user/dev/oss/async_ruby_test/rbnng/fiber_blocker/test/test_fiber_blocker.rb:40 [FINISH] c:0001 p:---- s:0003 e:000002 DUMMY [FINISH] -- Ruby level backtrace information ---------------------------------------- /home/user/dev/oss/async_ruby_test/rbnng/fiber_blocker/test/test_fiber_blocker.rb:40:in `block in test_fiber_blocking_in_ext' /home/user/dev/oss/async_ruby_test/rbnng/fiber_blocker/test/test_fiber_blocker.rb:40:in `block_fiber' -- Threading information --------------------------------------------------- Total ractor count: 1 Ruby thread count for this ractor: 4 -- Machine register context ------------------------------------------------ RIP: 0x00007f1554f17ad8 RBP: 0x00000000390d8f90 RSP: 0x00007f153a79e280 RAX: 0x00007f1554addba8 RBX: 0x00007f153a79eab0 RCX: 0x0000000000000000 RDX: 0x00007f1554ade600 RDI: 0x00007f15551e8788 RSI: 0x0000000000000ae1 R8: 0x000000000000002b R9: 0x00007f153a79f038 R10: 0x00007f1554c0b9b0 R11: 0x00007f153a79e490 R12: 0x0000000000000ae1 R13: 0x0000000000000000 R14: 0x0000000000000000 R15: 0x000055ab732d7df0 EFL: 0x0000000000010206 -- C level backtrace information ------------------------------------------- /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_print_backtrace+0x14) [0x7f1554f24961] /home/user/src/ruby-3.3.0/vm_dump.c:820 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_vm_bugreport) /home/user/src/ruby-3.3.0/vm_dump.c:1151 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_bug_for_fatal_signal+0x104) [0x7f1554d1c214] /home/user/src/ruby-3.3.0/error.c:1065 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(sigsegv+0x4f) [0x7f1554e700df] /home/user/src/ruby-3.3.0/signal.c:926 /lib/x86_64-linux-gnu/libc.so.6(0x7f1554842520) [0x7f1554842520] /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(RBASIC_CLASS+0x0) [0x7f1554f17ad8] ./include/ruby/internal/globals.h:178 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(gccct_method_search) /home/user/src/ruby-3.3.0/vm_eval.c:475 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_funcallv_scope) /home/user/src/ruby-3.3.0/vm_eval.c:1063 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_funcallv) /home/user/src/ruby-3.3.0/vm_eval.c:1084 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_inspect+0x19) [0x7f1554dc1569] /home/user/src/ruby-3.3.0/object.c:697 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(ruby__sfvextra+0x11a) [0x7f1554e7223a] /home/user/src/ruby-3.3.0/sprintf.c:1119 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(BSD_vfprintf+0xa69) [0x7f1554e73059] /home/user/src/ruby-3.3.0/vsnprintf.c:830 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(RBASIC_SET_CLASS_RAW+0x0) [0x7f1554e75b56] /home/user/src/ruby-3.3.0/sprintf.c:1168 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(ruby_vsprintf0) /home/user/src/ruby-3.3.0/sprintf.c:1169 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_enc_vsprintf+0x5d) [0x7f1554e75ecd] /home/user/src/ruby-3.3.0/sprintf.c:1195 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_sprintf+0x9d) [0x7f1554e7607d] /home/user/src/ruby-3.3.0/sprintf.c:1225 /home/user/dev/oss/async_ruby_test/rbnng/fiber_blocker/lib/fiber_blocker/fiber_blocker.so(block_fiber+0x4a) [0x7f1554ad430a] ../../../../ext/fiber_blocker/fiber_blocker.c:29 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_cfp_consistent_p+0x0) [0x7f1554ef64b4] /home/user/src/ruby-3.3.0/vm_insnhelper.c:3490 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_call_cfunc_with_frame_) /home/user/src/ruby-3.3.0/vm_insnhelper.c:3492 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_call_cfunc_with_frame) /home/user/src/ruby-3.3.0/vm_insnhelper.c:3518 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_call_cfunc_other) /home/user/src/ruby-3.3.0/vm_insnhelper.c:3544 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_sendish+0x9e) [0x7f1554f06f87] /home/user/src/ruby-3.3.0/vm_insnhelper.c:5581 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(vm_exec_core) /home/user/src/ruby-3.3.0/insns.def:834 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_vm_exec+0x19a) [0x7f1554f0d1fa] /home/user/src/ruby-3.3.0/vm.c:2486 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_vm_invoke_proc+0x5f) [0x7f1554f12e0f] /home/user/src/ruby-3.3.0/vm.c:1728 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_fiber_start+0x1ba) [0x7f1554cf098a] /home/user/src/ruby-3.3.0/cont.c:2536 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(fiber_entry+0x20) [0x7f1554cf0d00] /home/user/src/ruby-3.3.0/cont.c:847 /home/user/.rubies/ruby-3.3.0/lib/libruby.so.3.3(rb_threadptr_root_fiber_setup) (null):0 ``` I hope I'm not missing something obvious. My C isn't very good. -- https://bugs.ruby-lang.org/

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[ruby-core:126679] [Ruby Feature#19023] Enable riscv64 coroutines on riscv64-freebsd, arm32 on arm*-freebsd and ppc on powerpc-freebsd
by ioquatix (Samuel Williams) 13 Sep '26

13 Sep '26

Issue #19023 has been updated by ioquatix (Samuel Williams). Status changed from Open to Closed Fixed in <https://github.com/ruby/ruby/commit/066814022dcdaa361a06bb441ce30b11d4be0280>. ---------------------------------------- Feature #19023: Enable riscv64 coroutines on riscv64-freebsd, arm32 on arm*-freebsd and ppc on powerpc-freebsd https://bugs.ruby-lang.org/issues/19023#change-118974 * Author: pkubaj (Piotr Kubaj) * Status: Closed ---------------------------------------- Enable riscv64 coroutines on riscv64-freebsd, arm32 on arm*-freebsd and ppc on powerpc-freebsd https://github.com/ruby/ruby/pull/5852 -- https://bugs.ruby-lang.org/

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[ruby-core:124711] [Ruby Feature#21869] Add receive_all Method to Ractor API for Message Batching
by synacker (Mikhail Milovidov) 12 Sep '26

12 Sep '26

Issue #21869 has been reported by synacker (Mikhail Milovidov). ---------------------------------------- Feature #21869: Add receive_all Method to Ractor API for Message Batching https://bugs.ruby-lang.org/issues/21869 * Author: synacker (Mikhail Milovidov) * Status: Open ---------------------------------------- **Summary** The Ractor API provides an excellent mechanism for inter‑thread communication, but it currently lacks a built‑in message batching technique. I propose adding a receive_all method to enable batch processing of messages, which can significantly improve performance in high‑load scenarios. **Motivation** In distributed queued systems, processing messages one‑by‑one (as with the current receive method) can introduce unnecessary overhead. Batch processing allows: Reduced context‑switching overhead. More efficient I/O operations (e.g., fewer file writes). Better throughput in high‑concurrency environments. **Proposed Solution** Add a receive_all method to the Ractor API that: Returns all available messages in the Ractor’s mailbox at once (as an array). **Demonstration Code** Below is a benchmark comparing individual receive vs. batch receive_all: ``` ruby require 'benchmark' class RactorsTest def initialize(count) @count = count @ractor1 = Ractor.new(count, 'output1.txt') do |count, filename| File.open(filename, 'w') do |file| while count.positive? message = receive file.write("Ractor 1 received message: #{message}\n") file.flush count -= 1 end end end @ractor2 = Ractor.new(count, 'output2.txt') do |count, filename| File.open(filename, 'w') do |file| while count.positive? messages = receive_all messages.each do |message| file.write("Ractor 2 received message: #{message}\n") end count -= messages.length file.flush end end end end def run1 @count.times do |i| @ractor1.send("Message #{i + 1}") end @ractor1.join end def run2 @count.times do |i| @ractor2.send("Message #{i + 1}") end @ractor2.join end end records = 1_000_000 test = RactorsTest.new(records) p [:once, Benchmark.realtime { test.run1 }.round(2)] p [:all, Benchmark.realtime { test.run2 }.round(2)] ``` **Benchmark Results** On my system, receive_all shows ~4x improvement over individual receive: **Key Observations:** Ractor1 (using receive): Processes each message individually, resulting in frequent I/O calls. Ractor2 (using receive_all): Processes all queued messages at once, minimizing I/O overhead -- https://bugs.ruby-lang.org/

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[ruby-core:126672] [Ruby Bug#18661] Net::HTTP behavior changed between 2.6 and 3.1 on windows.
by hsbt (Hiroshi SHIBATA) 12 Sep '26

12 Sep '26

Issue #18661 has been updated by hsbt (Hiroshi SHIBATA). Status changed from Open to Closed Fixed on master by https://github.com/ruby/ruby/pull/18611. The hang is not inside `connect_nonblock`. Winsock reports a failed non-blocking `connect(2)` only through the exceptfds of `select(2)`, and `IO#wait_writable` never asks for that set, so `Addrinfo#connect_internal` kept waiting on a connection that had already been refused and burned the whole timeout. On Windows `Socket.tcp("127.0.0.1", <closed port>, connect_timeout: 5)` raised `Errno::ETIMEDOUT` after 5.01 seconds and now raises `Errno::ECONNREFUSED` after 2.06 seconds, which is Winsock's own latency before it reports the reset. `SO_ERROR` also carried a raw WinSock error code instead of an errno, so the failure surfaced as a bare `SystemCallError`. That is fixed as well. I could not reproduce the Rails system test end to end, so please reopen if it still hangs when you try it after the 4.1.0 release. ---------------------------------------- Bug #18661: Net::HTTP behavior changed between 2.6 and 3.1 on windows. https://bugs.ruby-lang.org/issues/18661#change-118969 * Author: jleblanc (Joshua LeBlanc) * Status: Closed * Assignee: windows * ruby -v: ruby 3.1.1p18 (2022-02-18 revision 53f5fc4236) [x64-mingw-ucrt] * Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN, 3.1: UNKNOWN ---------------------------------------- We are upgrading a rails application from Ruby 2.6 to Ruby 3.1 on Windows. Running rails systems tests hang on Ruby 3.1, while they succeed on Ruby 2.6. I tracked this down to Ruby 3.1's Net::HTTP using Socket.tcp rather than the old TCPSocket. Specifically, in `socket.rb`, `connect_internal` calls `connect_nonblock(self, exception: false)`, which ultimately hangs until timing out on windows. Modifying the `socket.rb` source to use `connect(self)` instead results in a successful operation. To be clear, the hanging operation is `socket.rb#connect_nonblock`, which is on line 1214 Reproduction: 1. Install Ruby 3.1 on Windows - I used RubyInstaller: https://github.com/oneclick/rubyinstaller2/releases/download/RubyInstaller-… 2. Clone the reproduction project: https://github.com/joshleblanc/windows_net_http_problem 3. Run `bundle install` 4. Run `rails test:system` Chrome will open, however a connection will never be made, ultimately timing out. To test this same process in earlier versions of ruby, simply create a new rails project with `rails new -O -J -S <name>`, add the `ffi` and `tzinfo-data` gems to the gemfile, and scaffold a new resource. Running `rails test:system` from this point should succeed. -- https://bugs.ruby-lang.org/

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[ruby-core:126523] [Ruby Misc#22272] Propose Kevin Menard (@nirvdrum) as a core committer
by tekknolagi (Maxwell Bernstein) 12 Sep '26

12 Sep '26

Issue #22272 has been reported by tekknolagi (Maxwell Bernstein). ---------------------------------------- Misc #22272: Propose Kevin Menard (@nirvdrum) as a core committer https://bugs.ruby-lang.org/issues/22272 * Author: tekknolagi (Maxwell Bernstein) * Status: Open * Assignee: core ---------------------------------------- ## Proposal I'd like to propose Kevin Menard (@nirvdrum) as a committer. He started full-time work on ZJIT about a year ago and has been doing excellent work since. For example, he wrote the function inliner, which is the single biggest lever a method-based compiler can have when trying to optimize code. He has years of compiler experience and additionally years of Ruby experience from working on TruffleRuby and CRuby. Especially since he has been contributing to Ruby for years now and knows the community, I think he should be able to merge his own changes. Here is Kevin's message: ## Kevin Menard's Message I've been active in the Ruby community since 2008. I started contributing performance improvements to Psych in 2012. I began contributing to CRuby in 2015 by diving into strings and reporting code range bugs. Since then I've contributed to the interpreter, YJIT, Prism, the Ruby Spec Suite, and several other Ruby org projects. I've been working extensively on ZJIT for the past nine months. A sample of my contributions include: * **ZJIT:** * Added method inlining to ZJIT ([ruby/ruby#16966](https://github.com/ruby/ruby/pull/16966)) * Optimized `super` calls to C functions in ZJIT ([ruby/ruby#15993](https://github.com/ruby/ruby/pull/15993/changes)) * **YJIT**: * Added a compilation log to YJIT ([ruby/ruby#11818](https://github.com/ruby/ruby/pull/11818)) * Optimized byte appends via `String#<<` ([ruby/ruby#11032](https://github.com/ruby/ruby/pull/11032)) * **Interpreter**: * Cheaply derive the code range for `String#b` ([ruby/ruby#6183](https://github.com/ruby/ruby/pull/6183)) * Optimized byte appends via `String#<<` ([ruby/ruby#10968](https://github.com/ruby/ruby/pull/10968)) * **Prism:** * Set `Regexp` encoding flags ([ruby/prism#2486](https://github.com/ruby/prism/pull/2486)) * Track `Symbol` encoding changes from source encoding ([ruby/prism#2268](https://github.com/ruby/prism/pull/2268)) Being a committer would make it much easier for me to contribute to ZJIT and keep up with its rapid pace of development. -- https://bugs.ruby-lang.org/

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[ruby-core:124851] [Ruby Bug#21918] fiber scheduler: fiber interrupt triggers for IOs that haven't been closed
by chucke (Tiago Cardoso) 12 Sep '26

12 Sep '26

Issue #21918 has been reported by chucke (Tiago Cardoso). ---------------------------------------- Bug #21918: fiber scheduler: fiber interrupt triggers for IOs that haven't been closed https://bugs.ruby-lang.org/issues/21918 * Author: chucke (Tiago Cardoso) * Status: Open * ruby -v: ruby 4.0.0 (2025-12-25 revision 553f1675f3) +PRISM [x86_64-linux] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN ---------------------------------------- I've been chasing an issue, which I believe is to with the recent introduction of the `fiber_interrupt` hook in ruby 4. As a reproduction I have the following snippet: ```ruby require "socket" require_relative "test/fiber/scheduler" # use the one defined here: https://github.com/ruby/ruby/blob/master/test/fiber/scheduler.rb udp = UDPSocket.new(Socket::AF_INET) tcp = Socket.new(Socket::AF_INET, :STREAM, 0) tcp.connect(Socket.sockaddr_in(80, "nghttp2")) t = Thread.start do Thread.current.abort_on_exception = true scheduler = Scheduler.new Fiber.set_scheduler scheduler 5.times do Fiber.schedule do begin puts "#{Fiber.current.object_id} -> wait udp" udp.to_io.wait_readable(2) rescue IOError => e puts "#{Fiber.current.object_id} -> udp io error: #{e}" end begin puts "#{Fiber.current.object_id} -> closing udp" udp.close puts "#{Fiber.current.object_id} -> closed udp" puts "#{Fiber.current.object_id} -> wait tcp" tcp.to_io.wait_readable(2) puts "#{Fiber.current.object_id} -> done" rescue => e puts "#{Fiber.current.object_id} -> tcp io error: #{e}" else puts "#{Fiber.current.object_id} -> closing tcp" tcp.close end end end end t.join ``` This produces the following output to me: ``` 1472 -> wait udp 1488 -> wait udp 1496 -> wait udp 1504 -> wait udp 1512 -> wait udp 1472 -> closing udp 1488 -> closing udp 1488 -> closed udp 1488 -> wait tcp 1496 -> closing udp 1496 -> closed udp 1496 -> wait tcp 1504 -> closing udp 1504 -> closed udp 1504 -> wait tcp 1512 -> closing udp 1512 -> closed udp 1512 -> wait tcp 1512 -> tcp io error: stream closed in another thread 1504 -> tcp io error: stream closed in another thread 1496 -> tcp io error: stream closed in another thread 1488 -> tcp io error: stream closed in another thread 1472 -> closed udp 1472 -> wait tcp 1472 -> done 1472 -> closing tcp ``` The thing that makes this program very confusing is that the "stream closed in another thread" related to the udp socket is raised while waiting for read readiness on the tcp socket. In such a situation, I'd expect the error to relate to the actual socket being waited on, not something else that fiber does not care about anymore. One thing that could have helped would be to have the reference of which IO object the exception relates to in the exception (aka `IOError#io` would return the socket). Nevertheless, I'd still consider an issue that this triggers in the wrong "fiber.yield" moment. Therefore, I think there are two possible outcomes here: 1. all fibers stop on `udp.close` until it is in fact closed (and then IOError is raised before the "closed udp" message can be printed) 2. exceptions related to IOs not actively being monitored by the current fiber are ignored. -- https://bugs.ruby-lang.org/

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[ruby-core:126667] [Ruby Feature#22308] Implement SHSTK support for AMD64 coroutines.
by ioquatix (Samuel Williams) 11 Sep '26

11 Sep '26

Issue #22308 has been reported by ioquatix (Samuel Williams). ---------------------------------------- Feature #22308: Implement SHSTK support for AMD64 coroutines. https://bugs.ruby-lang.org/issues/22308 * Author: ioquatix (Samuel Williams) * Status: Open * Assignee: ioquatix (Samuel Williams) ---------------------------------------- CRuby’s native AMD64 coroutine backend does not currently support Intel CET Shadow Stack (SHSTK). When SHSTK is active, coroutine transfers must switch both the regular stack pointer (SP) and shadow stack pointer (SSP). Each coroutine also requires its own shadow-stack allocation. Without this support, Fiber switching can trigger control-protection faults. Distributions currently need to build with --with-coroutine=ucontext or avoid enabling SHSTK. The ucontext backend has significant performance overhead compared with the native coroutine implementation. An implementation is being developed here: https://github.com/ruby/ruby/pull/5895 The proposed implementation: - Detects whether SHSTK is active at runtime. - Allocates and releases a shadow stack for each coroutine. - Initializes new shadow stacks with a valid return address. - Saves and restores SSP during coroutine transfers. - Advertises SHSTK support through the GNU property note. - Adds CI coverage that verifies SHSTK is genuinely active before running Fiber and continuation tests. IBT support has already been implemented separately; this issue concerns SHSTK support only. -- https://bugs.ruby-lang.org/

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[ruby-core:126668] [Ruby Bug#18061] Execshield test: libruby.so.N.N.N: FAIL: property-note test because no .note.gnu.property section found
by ioquatix (Samuel Williams) 11 Sep '26

11 Sep '26

Issue #18061 has been updated by ioquatix (Samuel Williams). Status changed from Open to Closed Implemented proper shadow stack support for AMD64 in https://github.com/ruby/ruby/commit/81757ddd75918130576cf7b050b057e0552591b4 ---------------------------------------- Bug #18061: Execshield test: libruby.so.N.N.N: FAIL: property-note test because no .note.gnu.property section found https://bugs.ruby-lang.org/issues/18061#change-118965 * Author: jaruga (Jun Aruga) * Status: Closed * Assignee: ioquatix (Samuel Williams) ---------------------------------------- I found an issue in our company's internal test called "execshield" by a security tool annobin - annocheck command [1][2]. ``` Hardened: libruby.so.2.7.4: FAIL: property-note test because no .note.gnu.property section found ``` Here is the reproducer on the upstream latest master, commit is 5f2987d6c2ae9ace3178ac3e1bbb4ac7079101eb, ``` $ autoconf $ ./configure --enable-shared $ make $ ls libruby.so.3.1.0 libruby.so.3.1.0* ``` If you are using Red Hat based Linux distro, it's easy to install by the RPM package like this. ``` $ sudo dnf -y install annobin-annocheck ``` ``` $ sudo yum -y install annobin-annocheck ``` Then ``` $ annocheck libruby.so.3.1.0 ``` If you are using other Linux distros such as Ubuntu, you can use it by a container I prepared. Prepare the following `Dockerfile`. ``` $ cat Dockerfile FROM docker.io/fedora:34 RUN cat /etc/fedora-release RUN dnf -y install annobin-annocheck WORKDIR /work ``` Then build the container image with the `Dockerfile` and run the annocheck command for the `libruby.so.3.1.0` on your host environment. The `-v` is an option for bind mount between host and container environment. ``` $ docker build --rm -t fedora-annocheck . $ docker run --rm -t -v $(pwd):/work fedora-annocheck annocheck /work/libruby.so.3.1.0 annocheck: Version 9.79. Hardened: libruby.so.3.1.0: FAIL: bind-now test because not linked with -Wl,-z,now Hardened: libruby.so.3.1.0: FAIL: notes test because gaps were detected in the annobin coverage Hardened: libruby.so.3.1.0: FAIL: cf-protection test because no .note.gnu.property section = no control flow information Hardened: libruby.so.3.1.0: FAIL: property-note test because no .note.gnu.property section found Hardened: Rerun annocheck with --verbose to see more information on the tests. ``` The message `Hardened: libruby.so.3.1.0: FAIL: property-note test because no .note.gnu.property section found` is what I found in our internal test. For other FAIL messages, maybe it can be fixed by changing how to build. Asking a colleague, I was told that the `coroutine/*/Context.S` files such as [coroutine/x86/Context.S](https://github.com/ruby/ruby/blob/master/coroutine… cause the failure. Do you have any idea how to fix this? Thanks. * [1] https://sourceware.org/annobin/ * [2] You can see `man annocheck` or https://www.mankier.com/1/annocheck . ---Files-------------------------------- 0001-Add-.note.gnu.property-sections.patch (2.64 KB) 0001-Add-.note.gnu.property-sections.patch (3.69 KB) config-pie.log (11.4 KB) -- https://bugs.ruby-lang.org/

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