From: stanhu@... Date: 2018-11-20T23:16:31+00:00 Subject: [ruby-core:89915] [Ruby trunk Bug#15325] Ruby 2.5.3 seg fault after find block returns Issue #15325 has been updated by stanhu (Stan Hu). Note that I've managed to remove the `return` statement inside the `find` block, and this appears to make the seg fault go away. ~~~diff diff --git a/app/services/ci/register_job_service.rb b/app/services/ci/register_job_service.rb index e06f1c05843..be01bfe95d8 100644 --- a/app/services/ci/register_job_service.rb +++ b/app/services/ci/register_job_service.rb @@ -36,7 +36,7 @@ module Ci builds = builds.with_any_tags end - builds.find do |build| + selection = builds.find do |build| next unless runner.can_pick?(build) begin @@ -45,7 +45,7 @@ module Ci if assign_runner!(build, params) register_success(build) - return Result.new(build, true) # rubocop:disable Cop/AvoidReturnFromBlocks + true end rescue StateMachines::InvalidTransition, ActiveRecord::StaleObjectError # We are looping to find another build that is not conflicting @@ -61,6 +61,8 @@ module Ci end end + return Result.new(selection, true) if selection + register_failure Result.new(nil, valid) end -- 2.18.1 ~~~ ---------------------------------------- Bug #15325: Ruby 2.5.3 seg fault after find block returns https://bugs.ruby-lang.org/issues/15325#change-74996 * Author: stanhu (Stan Hu) * Status: Open * Priority: Normal * Assignee: * Target version: * ruby -v: ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-darwin15] * Backport: 2.3: UNKNOWN, 2.4: UNKNOWN, 2.5: UNKNOWN ---------------------------------------- In https://gitlab.com/gitlab-org/gitlab-ce/blob/233af8f1731734aaad7e5055af39f26c16608649/app/services/ci/register_job_service.rb#L48, we see a repeatable seg fault on both MacOS and Ubuntu with Rails 5.0.7 in a development environment. The seg fault appears to occur after the `find` returns: ~~~ builds.find do |build| next unless runner.can_pick?(build) begin # In case when 2 runners try to assign the same build, second runner will be declined # with StateMachines::InvalidTransition or StaleObjectError when doing run! or save method. if assign_runner!(build, params) register_success(build) return Result.new(build, true) # <--- SEG FAULT HAPPENS AFTER HERE end rescue StateMachines::InvalidTransition, ActiveRecord::StaleObjectError ~~~ The segfault shows some bad memory access: ~~~ Thread 0 Crashed:: Dispatch queue: com.apple.main-thread 0 libsystem_kernel.dylib 0x00007fff5d0e8b86 __pthread_kill + 10 1 libsystem_pthread.dylib 0x00007fff5d19ec50 pthread_kill + 285 2 libsystem_c.dylib 0x00007fff5d0521c9 abort + 127 3 ruby 0x000000010f5ec6a9 die + 9 4 ruby 0x000000010f5ec908 rb_bug_context + 600 5 ruby 0x000000010f6db7a1 sigsegv + 81 6 libsystem_platform.dylib 0x00007fff5d193b3d _sigtramp + 29 7 ??? 000000000000000000 0 + 0 8 ruby 0x000000010f75461e vm_exec + 142 9 ruby 0x000000010f761f25 invoke_block_from_c_bh + 405 10 ruby 0x000000010f74f719 rb_yield + 153 11 ruby 0x000000010f5e33b9 find_i + 41 12 ruby 0x000000010f7620ca invoke_block_from_c_bh + 826 13 ruby 0x000000010f74f719 rb_yield + 153 14 ruby 0x000000010f57cce9 rb_ary_each + 41 15 ruby 0x000000010f759f51 vm_call_cfunc + 305 16 ruby 0x000000010f742a0d vm_exec_core + 9149 17 ruby 0x000000010f75461e vm_exec + 142 18 ruby 0x000000010f761d41 rb_call0 + 161 19 ruby 0x000000010f74fe54 iterate_method + 52 20 ruby 0x000000010f74fd9b rb_iterate0 + 347 21 ruby 0x000000010f74fe1a rb_block_call + 74 22 ruby 0x000000010f5e0518 enum_find + 104 23 ruby 0x000000010f759f51 vm_call_cfunc + 305 24 ruby 0x000000010f7436bd vm_exec_core + 12397 ~~~ We do NOT see the problem after downgrading to 2.4.5. ---Files-------------------------------- ruby_2018-11-20-132027_jet.crash (66.1 KB) ruby-2.5.3-segfault.txt (774 KB) -- https://bugs.ruby-lang.org/ Unsubscribe: