From: Felipe Balbi <balbi@ti.com>
To: Marcel Holtmann <marcel@holtmann.org>,
Alan Cox <alan@linux.intel.com>,
Greg KH <gregkh@linuxfoundation.org>
Cc: Muralidharan Karicheri <m-karicheri2@ti.com>,
linux-bluetooth@vger.kernel.org, linux-serial@vger.kernel.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: hci_ldsic nested locking problem
Date: Thu, 20 Mar 2014 11:34:35 -0500 [thread overview]
Message-ID: <20140320163435.GH32692@saruman.home> (raw)
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Hi,
when 8250 driver calls uart_write_wakeup(), the tty port lock is already
taken. hci_ldisc.c's implementation of ->write_wakeup() calls
tty->ops->write() to actually send the characters, but that call will
try to acquire the same port lock again.
Looking at other line disciplines that looks like a bug in hci_ldisc.c.
Am I correct to assume that ->write_wakeup() is supposed to *just*
wakeup the bottom half so we handle ->write() in another context ?
Is it legal to call tty->ops->write() from within ->write_wakeup() ?
cheers
--
balbi
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next reply other threads:[~2014-03-20 16:34 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-20 16:34 Felipe Balbi [this message]
[not found] ` <20140320163435.GH32692-HgARHv6XitL9zxVx7UNMDg@public.gmane.org>
2014-03-20 16:42 ` hci_ldsic nested locking problem Alan Cox
[not found] ` <1395333736.22077.32.camel-wU3TRTJX3O1FGiH78xh5akvbDziVy8sZEvhb3Hwu1Ks@public.gmane.org>
2014-03-20 17:16 ` Felipe Balbi
2014-03-20 17:29 ` Felipe Balbi
2014-03-20 17:34 ` Peter Hurley
2014-03-20 17:35 ` Felipe Balbi
[not found] ` <20140320173518.GD2827-HgARHv6XitL9zxVx7UNMDg@public.gmane.org>
2014-03-20 18:45 ` Greg KH
2014-03-20 18:54 ` Peter Hurley
2014-03-20 17:31 ` Peter Hurley
[not found] ` <532B25FC.3070408-WaGBZJeGNqdsbIuE7sb01tBPR1lH4CV8@public.gmane.org>
2014-03-20 18:11 ` Felipe Balbi
2014-03-20 18:21 ` Peter Hurley
2014-03-20 18:25 ` Felipe Balbi
2014-03-20 19:01 ` Felipe Balbi
2014-03-20 19:03 ` Felipe Balbi
2014-03-20 19:16 ` Peter Hurley
2014-03-20 19:25 ` Felipe Balbi
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