[ruby-core:69886] [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ruby-core:69886] [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been reported by Naohisa Goto.

----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:69889] Re: [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

Was there any output in stderr from this test?  Thanks.

[ruby-core:69893] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


>Was there any output in stderr from this test?

nothing

Recently, the failure message is changed to below.
It seems the SIGKILL is caused by timeout of the test.

~~~
TestProcess#test_exec_fd_3_redirect [/XXXXX-51186/test/ruby/test_process.rb:2038]:
assert_separately failed
pid 9248 killed by SIGKILL (signal 9)
~~~


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53311

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:69894] Re: [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

Can you try a higher fd number instead of 3?
Also, truss output would be useful.
Thanks.

[ruby-core:69895] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


Sometimes ASYNC BUG occurs, but it cannot be reproduced with truss.

~~~
$ ruby -e 'a = IO.pipe; b = IO.pipe; p a; p b; pid = fork { exec("ruby", "-e", "print IO.for_fd(3).read(1)", 3=>a[0],1=>b[1]) }; b[1].close; a[0].close; a[1].write("."); p b[0].read(1); Process.wait(pid)'
[#<IO:fd 7>, #<IO:fd 8>]
[#<IO:fd 9>, #<IO:fd 10>]
[ASYNC BUG] consume_communication_pipe: read

EBADF

ruby 2.3.0dev (2015-07-08) [sparc64-solaris2.10]

[NOTE]
You may have encountered a bug in the Ruby interpreter or extension libraries.
Bug reports are welcome.
For details: http://www.ruby-lang.org/bugreport.html

"."
~~~


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53313

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:69897] Re: [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

ngotogenome@gmail.com wrote:
> ~~~
> $ ruby -e 'a = IO.pipe; b = IO.pipe; p a; p b; pid = fork { exec("ruby", "-e", "print IO.for_fd(3).read(1)", 3=>a[0],1=>b[1]) }; b[1].close; a[0].close; a[1].write("."); p b[0].read(1); Process.wait(pid)'
> [#<IO:fd 7>, #<IO:fd 8>]
> [#<IO:fd 9>, #<IO:fd 10>]
> [ASYNC BUG] consume_communication_pipe: read

OK, I also hit the problem on a VM, too.

The problem is the timer thread is still running when we are performing
redirects for exec.

Can you try the following to stop the timer thread?

~~~
--- a/process.c
+++ b/process.c
@@ -2566,7 +2566,7 @@ rb_f_exec(int argc, const VALUE *argv)
 #if defined(__APPLE__) || defined(__HAIKU__)
     rb_exec_without_timer_thread(eargp, errmsg, sizeof(errmsg));
 #else
-    before_exec_async_signal_safe(); /* async-signal-safe */
+    before_exec(); /* NOT async-signal-safe */
     rb_exec_async_signal_safe(eargp, errmsg, sizeof(errmsg));
     preserving_errno(after_exec_async_signal_safe()); /* async-signal-safe */
 #endif
~~~

I will have limited Internet access the next few days.

Feel free to commit if it works for you; maybe the timer thread needs to
be restarted if execve fails, too (but the process will die).

Also, maybe the __APPLE__ || __HAIKU__ code above is suitable for all
OS, too.

In the coming weeks, we may also consider lazy spawning timer thread,
single-threaded scripts do not need it.

[ruby-core:69899] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


> Also, maybe the __APPLE__ || __HAIKU__ code above is suitable for all
OS, too.

I think so, and the following patch solves the failure ofTestProcess#test_exec_fd_3_redirect on Solaris 10.

~~~
Index: process.c
===================================================================
--- process.c   (revision 51194)
+++ process.c   (working copy)
@@ -2473,7 +2473,7 @@
     RB_GC_GUARD(execarg_obj);
 }
 
-#if defined(__APPLE__) || defined(__HAIKU__)
+#if defined(__APPLE__) || defined(__HAIKU__) || defined(__sun)
 static int rb_exec_without_timer_thread(const struct rb_execarg *eargp, char *errmsg, size_t errmsg_buflen);
 #endif
 
@@ -2563,7 +2563,7 @@
     rb_execarg_parent_start(execarg_obj);
     fail_str = eargp->use_shell ? eargp->invoke.sh.shell_script : eargp->invoke.cmd.command_name;
 
-#if defined(__APPLE__) || defined(__HAIKU__)
+#if defined(__APPLE__) || defined(__HAIKU__) || defined(__sun)
     rb_exec_without_timer_thread(eargp, errmsg, sizeof(errmsg));
 #else
     before_exec_async_signal_safe(); /* async-signal-safe */
@@ -3077,7 +3077,7 @@
     return -1;
 }
 
-#if defined(__APPLE__) || defined(__HAIKU__)
+#if defined(__APPLE__) || defined(__HAIKU__) || defined(__sun)
 static int
 rb_exec_without_timer_thread(const struct rb_execarg *eargp, char *errmsg, size_t errmsg_buflen)
 {
~~~


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53317

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:69934] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


The following example can reproduce the problem that the timer thread reads fd=3 after the redirection to fd=3 is set and before execve() is called, and then the script waits forever in b[0].read(1) and/or IO.for_fd(3).read(1). 

~~~
ruby -e 'a = IO.pipe; b = IO.pipe; p a; p b; opt = { 3=>a[0], 1=>b[1] }; (5..50).each { |i| opt[i] = "/dev/zero" }; pid = fork { exec("ruby", "-e", "print IO.for_fd(3).read(1)", opt)}; b[1].close; a[0].close; a[1].write("."); p b[0].read(1); Process.wait(pid)'
~~~

So, I also think stopping timer thread before execve is needed on all OS.

----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53356

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:69935] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


I forgot to mention that this was reproduced on x86_64 Linux.

----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53357

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70001] [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.

Status changed from Closed to Open

In r51265, I reverted r51209 because signals after stopping timer thread before entering exec(2) system call might be lost.

On Mac OS X and Haiku, the loss of signal still might occur. 

----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53436

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70005] Re: [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

Sorry, but I think rb_divert_reserved_fd seems a racy fix.  I think the
correct fix is to allow single-threaded Ruby to process signals without
timer thread; I will try to make it happen now.

[ruby-core:70023] Re: [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

I started working on this patch which causes pipes to always
be closed during timer thread shutdown.

http://80x24.org/spew/m/839ba256acbf1a5b17ad60953fc3ecf1df6cec50.txt

However, I may also eliminate timer thread entirely (on POSIX) by
using timer_create+timer_settime to deliver SIGVTALRM.

I also eliminated malloc from signal thread list (but not FGLOCK, yet),
but eliminating malloc may not be necessary.
http://80x24.org/spew/m/1437190754-29067-1-git-send-email-e@80x24.org.txt

[ruby-core:70050] Re: [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

Eric Wong <normalperson@yhbt.net> wrote:
> I started working on this patch which causes pipes to always
> be closed during timer thread shutdown.
> 
> http://80x24.org/spew/m/839ba256acbf1a5b17ad60953fc3ecf1df6cec50.txt

OK, need to check FD validity, too.  Still tricky:
http://80x24.org/spew/m/1437379741-6844-1-git-send-email-e@80x24.org.txt

> However, I may also eliminate timer thread entirely (on POSIX) by
> using timer_create+timer_settime to deliver SIGVTALRM.

Maybe...

[ruby-core:70008] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


> Sorry, but I think rb_divert_reserved_fd seems a racy fix.

Yes, it might be. Comparison and replacement of the fd is not atomic there, and calling dup2 after the rb_divert_reserved_fd is also a source of race.

Indeed, I implicitly expected that rb_divert_reserved_fd and dup2_with_divert were executed with GVL, but this might not be true in some cases.



----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53442

* Author: Naohisa Goto
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70041] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


With the patch, when exec system call fails, signals that are sent after stopping the timer thread before re-starting the timer thread may be ignored.

Currently, except Mac OS X and Haiku, the signals could be invoked after the failure of exec with no loss.


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53464

* Author: Naohisa Goto
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70048] Re: [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

ngotogenome@gmail.com wrote:
> With the patch, when exec system call fails, signals that are sent
> after stopping the timer thread before re-starting the timer thread
> may be ignored.

I'm not seeing it, did you notice/reproduce this failure?

I see:

1) rb_thread_stop_timer_thread()

2) signal received:
    sighandler
      -> signal_enque -> ATOMIC_INC(signal_buff.size) (++)
      -> rb_thread_wakeup_timer_thread -> noop since TT not running

3) exec fails

4) rb_thread_start_timer_thread()
    -> pthread_create(..., thread_timer)
      -> thread_timer
        -> timer_thread_function
          -> rb_threadptr_check_signal
            -> if (rb_signal_buff_size() > 0) { /* true from (++) */
                /* continue processing signals */

In other words, I'm not seeing a problem based on the (++) steps.

[ruby-core:70204] [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.


I'm sorry too late.

On Solaris 10, the patch works fine, with no error/failure during make test-all (with r51450).

> I'm not seeing it, did you notice/reproduce this failure?

No.
It seems the patch works correctly as you described.

I'm wondering whether the TODO in the following comment is still valid or not.
It seems it was first added in r32244 and was modified in r32276.

~~~
      /* close communication pipe */
      if (close_anyway) {
          /* TODO: Uninstall all signal handlers or mask all signals.
           *       This pass is cleaning phase (terminate ruby process).
           *       To avoid such race, we skip to close communication
           *       pipe.  OS will close it at process termination.
           *       It may not good practice, but pragmatic.
           *       We remain it is TODO.
           */
          /* close_communication_pipe(); */
      }
~~~


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53630

* Author: Naohisa Goto
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70206] Re: [Ruby trunk - Bug #11336] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

ngotogenome@gmail.com wrote:
> I'm sorry too late.

No worries, I don't have much time for ruby these few weeks, either.

> On Solaris 10, the patch works fine, with no error/failure during make test-all (with r51450).
> 
> > I'm not seeing it, did you notice/reproduce this failure?
> 
> No.
> It seems the patch works correctly as you described.
> 
> I'm wondering whether the TODO in the following comment is still valid or not.
> It seems it was first added in r32244 and was modified in r32276.

Not valid, I removed it in this patch [ruby-core:70050]:

http://80x24.org/spew/m/1437379741-6844-1-git-send-email-e@80x24.org.txt

[ruby-core:70386] [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.

Status changed from Closed to Open

I think the patch http://80x24.org/spew/m/1437379741-6844-1-git-send-email-e@80x24.org.txt is better not only for Solaris but also for other OSs.


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53789

* Author: Naohisa Goto
* Status: Open
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/

[ruby-core:70387] Re: [Ruby trunk - Bug #11336] [Open] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[Eric Wong]

ngotogenome@gmail.com wrote:
> I think the patch
> http://80x24.org/spew/m/1437379741-6844-1-git-send-email-e@80x24.org.txt
> is better not only for Solaris but also for other OSs.

OK, committed as r51576.  Hopefully there are no more issues with it,
but I still want to remove timer thread entirely soon

[ruby-core:70390] [Ruby trunk - Bug #11336] [Closed] TestProcess#test_exec_fd_3_redirect failed on Solaris 10

[ngotogenome]

Issue #11336 has been updated by Naohisa Goto.

Status changed from Open to Closed

memo:
r51576 fixes the bug (+ r51578 suppresses warning message)
r51268 is reverted by r51576


----------------------------------------
Bug #11336: TestProcess#test_exec_fd_3_redirect failed on Solaris 10
https://bugs.ruby-lang.org/issues/11336#change-53792

* Author: Naohisa Goto
* Status: Closed
* Priority: Normal
* Assignee: 
* ruby -v: ruby 2.3.0dev (2015-07-06) [sparc64-solaris2.10]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN
----------------------------------------
On Solaris 10, TestProcess#test_exec_fd_3_redirect failed since r51146 (where the test was added).

~~~
  1) Failure:
TestProcess#test_exec_fd_3_redirect [/XXXXX-51146/test/ruby/test_process.rb:2049]:
<"."> expected but was
<nil>.
~~~





-- 
https://bugs.ruby-lang.org/