Date: Mon, 20 Oct 2014 15:20:03 -0700
From: Stephen Boyd <sboyd@codeaurora.org>
To: Peter Hurley <peter@hurleysoftware.com>
Cc: Kumar Gala <galak@codeaurora.org>, gregkh@linuxfoundation.org,
        linux-kernel@vger.kernel.org,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        linux-arm-kernel@lists.infradead.org, Rob Herring <robh@kernel.org>
Subject: Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon
Message-ID: <20141020222003.GD12469@codeaurora.org>
References: <1413551588-14877-1-git-send-email-galak@codeaurora.org>
 <544553F6.1020409@codeaurora.org>
 <544580ED.3050604@hurleysoftware.com>
 <20141020221656.GC12469@codeaurora.org>
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On 10/20, Stephen Boyd wrote:
> On 10/20, Peter Hurley wrote:
> > 
> > FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does
> > not disable interrupts with spin_lock_irqsave().
> > 
> 
> Yeah we should fix that. As far as I can tell we've never used
> the irqsave variant of the lock in the console path. Did this
> become necessary at some point since this driver was introduced?
> I'm wondering how many stable trees need the fix.

Actually I don't see this case. It looks like the console is
always called in call_console_drivers() with irqs saved and
disabled via the logbuf_lock in console_cont_flush() or
console_unlock().

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