On Sun, Jun 03, 2012 at 08:54:20AM -0400, Ken Brown wrote: >On 6/2/2012 11:08 PM, Christopher Faylor wrote: >> On Fri, May 25, 2012 at 04:07:32PM -0400, Ken Brown wrote: >>> On 5/25/2012 2:49 PM, Ken Brown wrote: >>>> On 5/25/2012 10:35 AM, Corinna Vinschen wrote: >>>>> I applied a patch which calls the signal handler after cleanup. The >>>>> downside is that the signal handler is only called if select is called >>>>> from the main thread. A better patch would perhaps be to stop all >>>>> threads, call the signal handler, and restart the threads afterwards, >>>>> but this is more tricky. >>>> >>>> Thanks! That fixes it. I appreciate all your work on this. >>>> >>>> I'm in the process now of testing to see if this also fixes an emacs >>>> crash I've been getting when I build emacs with GSettings support >>>> (http://cygwin.com/ml/cygwin-xfree/2012-04/msg00048.html). >>> >>> Here's what I'm now seeing with that build. If I start emacs and do >>> 'M-x shell', emacs hangs (but doesn't crash). Attaching gdb and doing a >>> backtrace of all threads, I see that cygwin_select has been called in >>> two threads other than the main one: >>> >>> Thread 8 (Thread 2784.0x19c): >>> #0 0x7702013d in ntdll!RtlEnableEarlyCriticalSectionEventCreation () >>> from /c/windows/SysWOW64/ntdll.dll >>> #1 0x7702013d in ntdll!RtlEnableEarlyCriticalSectionEventCreation () >>> from /c/windows/SysWOW64/ntdll.dll >>> #2 0x74fe0bdd in WaitForMultipleObjectsEx () >>> from /c/windows/syswow64/KERNELBASE.dll >>> #3 0x00000004 in ?? () >>> #4 0x74ed1a2c in KERNEL32!GetVolumePathNamesForVolumeNameA () >>> from /c/windows/syswow64/kernel32.dll >>> #5 0xff11c868 in ?? () >>> #6 0x74ed4208 in KERNEL32!CheckForReadOnlyResource () >>> from /c/windows/syswow64/kernel32.dll >>> #7 0x00000004 in ?? () >>> #8 0x610d0b24 in select_stuff::wait (this=0xff11cba4, readfds=0xff11cb00, >>> writefds=0xff11cae0, exceptfds=0xff11cac0, ms=4294967295) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/select.cc:320 >>> #9 0x610d154b in cygwin_select (maxfds=13, readfds=0xff11cc70, >>> writefds=0xff11cc50, exceptfds=0xff11cc30, to=0x0) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/select.cc:158 >>> #10 0x610b2b5a in poll (fds=0x8012db00, nfds=3, timeout=-1) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/poll.cc:87 >>> #11 0x610d5575 in _sigfe () from /usr/bin/cygwin1.dll >>> #12 0xffffffff in ?? () >>> #13 0x8012db00 in ?? () >>> #14 0x6ac1e759 in g_main_loop_run () from /usr/bin/cygglib-2.0-0.dll >>> #15 0x6ad96d40 in g_dbus_proxy_call_with_unix_fd_list_sync () >>> from /usr/bin/cyggio-2.0-0.dll >>> #16 0x6ac401ef in g_thread_proxy () from /usr/bin/cygglib-2.0-0.dll >>> #17 0x610fca42 in pthread::thread_init_wrapper (arg=0x80130e00) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/thread.cc:2104 >>> #18 0x61086f62 in thread_wrapper (arg=0x0) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/miscfuncs.cc:547 >>> #19 0x00000000 in ?? () >>> >>> Thread 7 (Thread 2784.0xb4c): >>> #0 0x7702013d in ntdll!RtlEnableEarlyCriticalSectionEventCreation () >>> from /c/windows/SysWOW64/ntdll.dll >>> #1 0x7702013d in ntdll!RtlEnableEarlyCriticalSectionEventCreation () >>> from /c/windows/SysWOW64/ntdll.dll >>> #2 0x74fe0bdd in WaitForMultipleObjectsEx () >>> from /c/windows/syswow64/KERNELBASE.dll >>> #3 0x00000003 in ?? () >>> #4 0x74ed1a2c in KERNEL32!GetVolumePathNamesForVolumeNameA () >>> from /c/windows/syswow64/kernel32.dll >>> #5 0xff21c858 in ?? () >>> #6 0x74ed4208 in KERNEL32!CheckForReadOnlyResource () >>> from /c/windows/syswow64/kernel32.dll >>> #7 0x00000003 in ?? () >>> #8 0x610d0b24 in select_stuff::wait (this=0xff21cb94, readfds=0xff21caf0, >>> writefds=0xff21cad0, exceptfds=0xff21cab0, ms=4294967295) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/select.cc:320 >>> #9 0x610d154b in cygwin_select (maxfds=8, readfds=0xff21cc60, >>> writefds=0xff21cc40, exceptfds=0xff21cc20, to=0x0) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/select.cc:158 >>> #10 0x610b2b5a in poll (fds=0x8009b3c0, nfds=1, timeout=-1) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/poll.cc:87 >>> #11 0x610d5575 in _sigfe () from /usr/bin/cygwin1.dll >>> #12 0xffffffff in ?? () >>> #13 0x8009b3c0 in ?? () >>> #14 0x6ac1e759 in g_main_loop_run () from /usr/bin/cygglib-2.0-0.dll >>> #15 0x63e32eca in gvdb_table_walk () >>> from /usr/lib/gio/modules/cygdconfsettings.dll >>> #16 0x6ac401ef in g_thread_proxy () from /usr/bin/cygglib-2.0-0.dll >>> #17 0x610fca42 in pthread::thread_init_wrapper (arg=0x8009c700) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/thread.cc:2104 >>> #18 0x61086f62 in thread_wrapper (arg=0x0) >>> at >>> /ext/build/netrel/src/cygwin-snapshot-20120525-1/winsup/cygwin/miscfuncs.cc:547 >>> #19 0x00000000 in ?? () >>> >>> It looks like these threads are being used by GLib, which is running a >>> loop that calls poll, which calls cygwin_select. So maybe the "better >>> patch" that you referred to would fix this hang. >> >> Ken, can you confirm/deny that the changes that I just made to select() >> at least still work as well as Corinna's temporary (that's what the >> ChangeLog says at least) change above? They are in the latest snapshot. > >No, they don't. There's no crash, but I'm seeing two problems in emacs >and a problem with the X server. My emacs tests were done with emacs-24 >in mintty on 64-bit Windows 7. I wanted to test it under X also, but I >couldn't because of the X server problem. > >1. When I type into emacs, it's very slow to echo the keystrokes and >respond. > >2. When I start a shell under emacs (<Alt-X>shell<return>), the shell >doesn't finish initializing. It doesn't display a prompt, and it >doesn't execute commands I type. > >3. If I start the X server using the Start Menu shortcut, startxwin >never finishes, and the xterm window doesn't display. I have to kill >startxwin from a terminal.
All of the above should be fixed in the upcoming snapshot. Sorry for wasting your time with this. It was late and I didn't do the basic checking that I should have before checking this in. I had a very stupid typo in the last snapshot. cgf -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple