Date: Sat, 13 Nov 2010 17:42:40 +0000
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Greg KH <gregkh@suse.de>
Cc: Alexey Zaytsev <alexey.zaytsev@gmail.com>, linux-kernel@vger.kernel.org,
        Lawrence Rust <lvr@softsystem.co.uk>
Subject: Re: [PATCH 11/19] 8250: Fix tcsetattr to avoid ioctl(TIOCMIWAIT)
 hang
Message-ID: <20101113174240.2bfb79dd@lxorguk.ukuu.org.uk>
In-Reply-To: <20101113144954.GA29977@suse.de>
References: <20101112213215.GB9294@kroah.com>
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> Lawrence, any ideas?  If not, I'm going to have to revert this patch
> from the tree.

Peering into the waitqueues like that isn't going to work.

I'd suggest simply keeping a proper count (locked) of the number of
people sitting in TIOCMIWAIT, and probably do it in serial_core (because
the bug doesn't look 8250 specific)

Alan
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