edb-postgres.exe has encountered a problem on windows

Started by Rushabh Lathiaalmost 15 years ago5 messages
#1Rushabh Lathia
rushabh.lathia@gmail.com
1 attachment(s)

Problem:
========

On windows when we run edb-postgres.exe without any command line args, its
getting crash or its showing error into Application logs of Event Viewer.

Analysis:
==========

For any stderr we call the write_stderr() and write_stderr() calls the
write_console() for stderr. Now here write_console() using the palloc()
internally, which require the CurrentMemoryContext.

At the startup CurrentMemoryContext will be NULL, so palloc again calling
write_stderr(). So recursion has been started and its ending up with
exception.

Call stack for palloc() is:

main() -> check_root() -> write_stderr() -> write_console() ->
pgwin32_toUTF16() -> palloc()

Fix:
=====

Earlier we used to call vfprintf() for windows stderr, which is now
replaced with write_console().
So to avoid the exception now, I added condition for CurrentMemoryContext
into write_stderr().

PFA patch to fix the same.

Regards,
Rushabh Lathia
EnterpriseDB <http://www.enterprisedb.com/&gt;, The Enterprise
PostgreSQL<http://www.enterprisedb.com/&gt;
company.

Attachments:

win_crash_fix.patchtext/x-diff; charset=US-ASCII; name=win_crash_fix.patchDownload
Index: src/backend/utils/error/elog.c
===================================================================
RCS file: /repositories/postgreshome/cvs/pgsql/src/backend/utils/error/elog.c,v
retrieving revision 1.226
diff -c -p -r1.226 elog.c
*** src/backend/utils/error/elog.c	19 Aug 2010 22:55:01 -0000	1.226
--- src/backend/utils/error/elog.c	1 Apr 2011 14:08:38 -0000
*************** write_stderr(const char *fmt,...)
*** 2759,2766 ****
  	}
  	else
  	{
! 		/* Not running as service, write to stderr */
! 		write_console(errbuf, strlen(errbuf));
  		fflush(stderr);
  	}
  #endif
--- 2759,2773 ----
  	}
  	else
  	{
! 		/* 
! 		 * To use the write_console we need memoryContext as its using palloc
! 		 * internally. When we don't have CurrentMemoryContext directly throw
! 		 * error at stderr.
! 		 */
! 		if (CurrentMemoryContext)
! 			write_console(errbuf, strlen(errbuf));
! 		else
! 			vfprintf(stderr, fmt, ap);
  		fflush(stderr);
  	}
  #endif
#2Magnus Hagander
magnus@hagander.net
In reply to: Rushabh Lathia (#1)
Re: edb-postgres.exe has encountered a problem on windows

On Fri, Apr 1, 2011 at 15:14, Rushabh Lathia <rushabh.lathia@gmail.com> wrote:

Problem:
========

On windows when we run edb-postgres.exe without any command line args, its
getting crash or its showing error into Application logs of Event Viewer.

Analysis:
==========

For any stderr we call the write_stderr() and write_stderr() calls the
write_console() for stderr. Now here write_console() using the palloc()
internally, which require the CurrentMemoryContext.

At the startup CurrentMemoryContext will be NULL, so palloc again calling
write_stderr(). So recursion has been started and its ending up with
exception.

Call stack for palloc() is:

main() -> check_root() -> write_stderr() -> write_console() ->
pgwin32_toUTF16() -> palloc()

Fix:
=====

Earlier  we used to call vfprintf() for windows stderr, which is now
replaced with write_console().
So to avoid the exception now, I added condition for CurrentMemoryContext
into write_stderr().

PFA patch to fix the same.

What about the cases where we directly call write_console()? Do we
know we are good there, or should the check perhaps be made inside
write_console() instead of in the caller?

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/

#3Robert Haas
robertmhaas@gmail.com
In reply to: Rushabh Lathia (#1)
Re: edb-postgres.exe has encountered a problem on windows

On Fri, Apr 1, 2011 at 9:14 AM, Rushabh Lathia <rushabh.lathia@gmail.com> wrote:

On windows when we run edb-postgres.exe ...

Did you intend to send this to an EDB-internal mailing list?

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

#4Heikki Linnakangas
heikki.linnakangas@enterprisedb.com
In reply to: Robert Haas (#3)
Re: edb-postgres.exe has encountered a problem on windows

On 01.04.2011 16:56, Robert Haas wrote:

On Fri, Apr 1, 2011 at 9:14 AM, Rushabh Lathia<rushabh.lathia@gmail.com> wrote:

On windows when we run edb-postgres.exe ...

Did you intend to send this to an EDB-internal mailing list?

I think he just forgot to search & replace edb-postgres.exe to
postgres.exe ;-). The issue was found originally on Advanced Server, but
there is nothing EDB-specific there and the same bug is in community
PostgreSQL.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com

#5Rushabh Lathia
rushabh.lathia@gmail.com
In reply to: Robert Haas (#3)
Re: edb-postgres.exe has encountered a problem on windows

On Fri, Apr 1, 2011 at 7:26 PM, Robert Haas <robertmhaas@gmail.com> wrote:

On Fri, Apr 1, 2011 at 9:14 AM, Rushabh Lathia <rushabh.lathia@gmail.com>
wrote:

On windows when we run edb-postgres.exe ...

Did you intend to send this to an EDB-internal mailing list?

Oops sorry, initially we found this bug with EDB.

But after looking into issue more I found that its also present into
postgreSQL.

Need to replace edb-postgres.exe with postgres.exe ..

Regards,
Rushabh Lathia
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company