From owner-freebsd-hackers@FreeBSD.ORG  Mon Nov 21 08:16:32 2005
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From: "Konstantin Prokazoff" <kprokazov@svr.kiev.ua>
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Date: Mon, 21 Nov 2005 10:29:32 +0200
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Subject: poll()/select()
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Welcome everybody,

    have a strange issue under 5.x/6.x (checked).
    When using a poll()/select() mechanism, which in kernel based on
selrecord/selwakeup (pollscan, kern_select) functions, we have deadlock on
sellock mutex on heavy load (recursive lock on non-recursive mutex). Have
anyone seen this? Deadlock can be reached only if kernel w'be compiled with
debugger, because in different case system locks, your can't login, etc.
Maybe one path to resolve - change behavour of sched_lock & sellock mutexes
block/unblock order.
    Thnx in advance & for comments.

Best regards,
        Konstantin Prokazoff
Center Of Excellence, S_V_R Ltd., Kyiv HQs, Ukraine
Official business-partner & DevConnect member of Avaya Inc.
Regional development & support center of Digium Inc.
Tel. +38 044 244 1181, ext. 1038
Fax. +38 044 234 0455