Re: 2.6.25.3: su gets stuck for root

From: Willy Tarreau
Date: Tue May 20 2008 - 16:39:03 EST


On Tue, May 20, 2008 at 10:26:16PM +0200, Harald Dunkel wrote:
> david@xxxxxxx wrote:
> >
> >try killing syslog and then see if you continue to have the problem.
> >It's possible that what's happening is syslog is getting stuck and su is
> >sitting waiting for syslog to process the log entry.
> >
>
> No improvement: I killed syslogd, and yet stty gets stuck.
>
> But surely it was a smart idea.

have you checked in /proc/$(pidof stty)/fd/ to see if stty is bound to
any particular file descriptor ? Maybe you'll find the source of the
blocking operation here. You can find a unix socket attached to
another process, it may be a tty, a pipe, or even a device (eg:
/dev/random when there is no entropy left). Same for "su" BTW.

Regards,
willy

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/