Mail Archives: cygwin/2012/05/25/16:08:25
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
--
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
- Raw text -