Subject: Re: kern/32682: netbsd-3 ptyfs intermittent failure with Matlab
To: None <kern-bug-people@netbsd.org, gnats-admin@netbsd.org,>
From: Christos Zoulas <christos@zoulas.com>
List: netbsd-bugs
Date: 02/08/2006 17:40:02
The following reply was made to PR kern/32682; it has been noted by GNATS.
From: christos@zoulas.com (Christos Zoulas)
To: Hauke Fath <hf@spg.tu-darmstadt.de>
Cc: gnats-bugs@NetBSD.org, kern-bug-people@NetBSD.org,
gnats-admin@NetBSD.org
Subject: Re: kern/32682: netbsd-3 ptyfs intermittent failure with Matlab
Date: Wed, 8 Feb 2006 12:35:08 -0500
On Feb 8, 4:55pm, hf@spg.tu-darmstadt.de (Hauke Fath) wrote:
-- Subject: Re: kern/32682: netbsd-3 ptyfs intermittent failure with Matlab
| I finally managed to get hold of an error instance...
|
| Ktracing Matlab 14 gave me
|
| [tj@Katzenbuckel clpois]$ kdump | less
|
| [...]
|
| 25647 MATLAB CALL open(0xbac662e0,0x8002,0)
| 25647 MATLAB NAMI "/emul/linux/dev/pts/5"
| 25647 MATLAB NAMI "/dev/pts/5"
| 25647 MATLAB RET open -1 errno -13 Permission denied
|
|
| Am 31.01.2006 um 12:52 Uhr -0500 schrieb Christos Zoulas:
| >Can you show what w(1) prints
|
| Katzenbuckel# w
| 1:20PM up 6 days, 5:46, 1 user, load averages: 1.19, 1.49, 1.59
| USER TTY FROM LOGIN@ IDLE WHAT
| tj :0 - Thu07AM ? /bin/sh /usr/pkg/bin/startkde
|
| >and the "interesting" ptys in /dev/[pt]ty??.
|
| [tj@Katzenbuckel clpois]$ ll /dev/pts/
| total 31
| dr-xr-xr-x 1 root wheel 512 Feb 2 07:50 ./
| drwxr-xr-x 5 root wheel 30720 Oct 23 03:27 ../
| crw-rw-rw- 1 root wheel 3, 0 Oct 22 23:25 0
| crw-rw-rw- 1 root wheel 3, 1 Feb 3 03:15 1
| crw-rw-rw- 1 root wheel 3, 2 Feb 8 07:21 2
| crw--w---- 1 hf tty 3, 3 Feb 2 11:28 3
| crw-rw-rw- 1 root wheel 3, 4 Feb 8 09:39 4
|
| >I suspect what is going on, is that you have a rogue program that is
| >opening old style pty's behind the pty subsystem's back, so when ptyfs
| >tries to open the same pty, it fails. So when it fails for pts/4 for
| >example, what does lsof say for /dev/{t,p}typ4?
|
| Is lsof tied to the OS version? I got a warning "...compiled for
| NetBSD 2" and no output.
|
| fstat(1) gave me
|
| Katzenbuckel# fstat /dev/ttyp5
| USER CMD PID FD MOUNT INUM MODE SZ|DV R/W NAME
| root fstat 8778 0 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root fstat 8778 1 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root fstat 8778 2 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root tcsh 19818 15 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root tcsh 19818 16 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root tcsh 19818 17 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root tcsh 19818 18 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| root tcsh 19818 19 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| hf tcsh 21122 15 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| hf tcsh 21122 16 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| hf tcsh 21122 17 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| hf tcsh 21122 18 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| hf tcsh 21122 19 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| tj bash 24622 0 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| tj bash 24622 1 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| tj bash 24622 2 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| tj bash 24622 255 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| tj kdeinit 902 20 / 1855043 crw-rw-rw- ttyp5 rw
| /dev/ttyp5
| Katzenbuckel# fstat /dev/ptyp5
| USER CMD PID FD MOUNT INUM MODE SZ|DV R/W NAME
| tj kdeinit 902 19 / 1854014 crw-rw-rw- ptyp5 rw
| /dev/ptyp5
|
|
| -- The latter is kind of interesting. What confused me, though, is
| that after logging out and logging in again, Matlab did still fail
| but an fstat for the relevant {p,t}typ? came up empty.
|
| As a further data point, a coworker who uses Gnome exclusively claims
| he has never seen the error (most of the people here use KDE). ISTR,
| though, that I have seen Matlab fail under XFCE4 - which is set up to
| start the KDE and Gnome daemons. Hmmm...
|
| Anything else that I could check?
|
| hauke
This is great information. Now what application opened the pty? kde terminal?
This is the application that is not using openpty and it is trying to open
pty's directly.
christos