Date: Sat, 23 Jul 2005 00:53:20 +0200 (CEST) From: Paweł Jakub Dawidek <pjd@FreeBSD.org> To: FreeBSD-gnats-submit@FreeBSD.org Cc: sam@FreeBSD.org Subject: kern/83930: crypto_q_mtx recursion when unloading hifn.ko. Message-ID: <20050722225320.0F460ACAF4@darkness.comp.waw.pl> Resent-Message-ID: <200507222300.j6MN0W6m034849@freefall.freebsd.org>
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>Number: 83930
>Category: kern
>Synopsis: crypto_q_mtx recursion when unloading hifn.ko.
>Confidential: no
>Severity: serious
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Fri Jul 22 23:00:32 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator: Pawel Jakub Dawidek
>Release: FreeBSD 5.x
>Organization:
>Environment:
>Description:
I had a panic related to mutex recursion when unloading hifn.ko module.
The code path is as follows:
crypto_dispatch()
CRYPTO_Q_LOCK()
crypto_invoke()
crypto_done()
cryptodev_cb() (via crp->crp_callback)
crypto_dispatch()
CRYPTO_Q_LOCK() <- recursion.
>How-To-Repeat:
>Fix:
Not sure how to fix it. Calling 'locked' version of crypto_dispatch()
is not an option, as we can call cryptodev_cb() with or without
crypto_q_mtx held.
The only fix I can came up with right not is a "pseudo-recursion" in
crypto_dispatch():
int unlock = 0;
[...]
if (!mtx_owned(&crypto_q_mtx)) {
unlock = 1;
CRYPTO_Q_LOCK();
}
[...]
if (unlock)
CRYPTO_Q_LOCK();
>Release-Note:
>Audit-Trail:
>Unformatted:
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