Deadlocked cygrunsrv processes with strace message _cygtls::remove: wait 0x0
Something about Apache 2 is causing its controlling cygrunsrv service process to deadlock within the Cygwin DLL when it attempts to exit. Attaching with strace to the hung process shows _cygtls::remove: wait 0x0. Signals sent to the hung process are not delivered (as shown by strace), but a kill -9 will succeed. Attaching with gdb does show anything that looks promising. Does anyone have any suggestions that could save me some time, compared to an in-depth study of the Cygwin DLL code in this area? Max. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
Re: Deadlocked cygrunsrv processes with strace message _cygtls::remove: wait 0x0
Max Bowsher wrote: Something about Apache 2 is causing its controlling cygrunsrv service process to deadlock within the Cygwin DLL when it attempts to exit. Attaching with strace to the hung process shows _cygtls::remove: wait 0x0. Signals sent to the hung process are not delivered (as shown by strace), but a kill -9 will succeed. Attaching with gdb does show anything that looks promising. Does anyone have any suggestions that could save me some time, compared to an in-depth study of the Cygwin DLL code in this area? Um. Oh. Dear. Since gdb backtrace wasn't helpful, I decided to try single stepping in gdb onwards from the last strace output. I found out that _cygtls.remove is being called successfully from dll_entry(DLL_THREAD_DETACH), which returns, and the hang finally occurs inside ZwTerminateThread() !!! What now? Do I scream and give up? Max. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
Re: Deadlocked cygrunsrv processes with strace message _cygtls::remove: wait 0x0
On Mon, Apr 11, 2005 at 01:20:52PM +0100, Max Bowsher wrote: Max Bowsher wrote: Something about Apache 2 is causing its controlling cygrunsrv service process to deadlock within the Cygwin DLL when it attempts to exit. Attaching with strace to the hung process shows _cygtls::remove: wait 0x0. Signals sent to the hung process are not delivered (as shown by strace), but a kill -9 will succeed. Attaching with gdb does show anything that looks promising. Does anyone have any suggestions that could save me some time, compared to an in-depth study of the Cygwin DLL code in this area? Um. Oh. Dear. Since gdb backtrace wasn't helpful, I decided to try single stepping in gdb onwards from the last strace output. I found out that _cygtls.remove is being called successfully from dll_entry(DLL_THREAD_DETACH), which returns, and the hang finally occurs inside ZwTerminateThread() !!! What now? Do I scream and give up? That's what I'd suggest. cgf -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
